Journal articles: 'Nanostructures - Surfaces'

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Reddy, G. S., Mallikarjuna N. Nadagouda, and Jainagesh A. Sekhar. "Nanostructured Surfaces that Show Antimicrobial, Anticorrosive, and Antibiofilm Properties." Key Engineering Materials 521 (August 2012): 1–33. http://dx.doi.org/10.4028/www.scientific.net/kem.521.1.

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Provided in this article are the quantitative and qualitative morphological results describing the action of several nanostructured surfaces for bactericidal and bacteriostatic action. Results are also provided to illustrate microbial corrosion and its impact. Biofilm formation is correlated to colony formation. Nanostructured surfaces, i.e. surfaces with welded nanoparticles are noted to display biocidal activity with varying efficacies. Porous nanostructures, on stainless steel and copper substrates, made of high purity Ag, Ti, Al, Cu, MoSi2, and carbon nanotubes, are tested for their efficacy against bacterial colony formation for both gram-negative, and gram-positive bacteria. Silver and Molybdenum disilicide (MoSi2) nanostructures are found to be the most effective bactericidal agents with MoSi2 being particularly effective in both low and high humidity conditions. Bacteriostatic activity is also noted. The nanostructured surfaces are tested by controlled exposures to several microbial species including (Gram+ve) bacteria such as Bacillus Cereus and (Gram-ve) bacteria such as Enterobacter Aerogenes. The resistance to simultaneous exposure from diverse bacterial species including Arthrobacter Globiformis, Bacillus Megaterium, and Cupriavidus Necator is also studied. The nanostructured surfaces were found to eliminates or delay bacterial colony formation, even with short exposure times, and even after simulated surface abrasion. The virgin 316 stainless steel and copper substrates, i.e. without the nanostructure, always displayed rapid bacterial colony evolution indicating the lack of antimicrobial action. The efficacy of the nanostructured surface against colony formation (bacterial recovery) for E-Coli (two strains) and virus Phi 6 Bacteriophage with a host Pseudomonas Syringae was also studied. Preliminary results are presented that also show possible anti-fungal properties by the nanostructured MoSi2. When comparing antimicrobial efficacy of flat polished surfaces (no curvature or nanostructure) with nanostructure containing surfaces (high curvature) of the same chemistry, shows that bacterial action results from both the nanostructure size and chemistry.

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Cho, Seong J., Se Yeong Seok, Jin Young Kim, Geunbae Lim, and Hoon Lim. "One-Step Fabrication of Hierarchically Structured Silicon Surfaces and Modification of Their Morphologies Using Sacrificial Layers." Journal of Nanomaterials 2013 (2013): 1–8. http://dx.doi.org/10.1155/2013/289256.

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Fabrication of one-dimensional nanostructures is a key issue for optical devices, fluidic devices, and solar cells because of their unique functionalities such as antireflection and superhydrophobicity. Here, we report a novel one-step process to fabricate patternable hierarchical structures consisting of microstructures and one-dimensional nanostructures using a sacrificial layer. The layer plays a role as not only a micromask for producing microstructures but also as a nanomask for nanostructures according to the etching time. Using this method, we fabricated patterned hierarchical structures, with the ability to control the shape and density of the nanostructure. The various architectures provided unique functionalities. For example, our sacrificial-layer etching method allowed nanostructures denser than what would be attainable with conventional processes to form. The dense nanostructure resulted in a very low reflectance of the silicon surface (less than 1%). The nanostructured surface and hierarchically structured surface also exhibited excellent antiwetting properties, with a high contact angle (>165°) and low sliding angle (<1°). We believe that our fabrication approach will provide new insight into functional surfaces, such as those used for antiwetting and antireflection surface applications.

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Hariharalakshmanan, Ranjitha K., Fumiya Watanabe, and Tansel Karabacak. "In Situ Growth and UV Photocatalytic Effect of ZnO Nanostructures on a Zn Plate Immersed in Methylene Blue." Catalysts 12, no. 12 (December 16, 2022): 1657. http://dx.doi.org/10.3390/catal12121657.

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Nanostructures of zinc oxide (ZnO) are considered promising photocatalysts for the degradation of organic pollutants in water. This work discusses an in situ growth and UV photocatalytic effect of ZnO nanostructures on a Zn plate immersed in methylene blue (MB) at room temperature. First, the Zn surfaces were pretreated via sandblasting to introduce a micro-scale roughness. Then, the Zn plates were immersed in MB and exposed to UV light, to observe ZnO nanostructure growth and photocatalytic degradation of MB. Scanning electron microscopy, energy dispersive spectroscopy, X-ray diffraction, X-ray photoelectron spectroscopy, and UV-Vis diffuse reflectance spectroscopy were used to characterize the Zn surfaces. We observed the growth of stoichiometric and crystalline ZnO with a nano-leaf morphology and an estimated bandgap of 3.08 eV. The photocatalytic degradation of MB was also observed in the presence of the ZnO nanostructures and UV light. The average percentage degradation was 76% in 4 h, and the degradation rate constant was 0.3535 h−1. The experimental results suggest that room temperature growth of ZnO nanostructures (on Zn surfaces) in organic dye solutions is possible. Furthermore, the nanostructured surface can be used simultaneously for the photocatalytic degradation of the organic dye.

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Wang, Yuliang, Xiaolai Li, Shuai Ren, Hadush Tedros Alem, Lijun Yang, and Detlef Lohse. "Entrapment of interfacial nanobubbles on nano-structured surfaces." Soft Matter 13, no. 32 (2017): 5381–88. http://dx.doi.org/10.1039/c7sm01205e.

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The nucleation mechanism of interfacial nanobubbles is revealed on immersed nanostructured hydrophobic surfaces. The result shows that surface nanostructures play a key role in controlling nanobubbles' size, position, and even morphology.

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Mansurov, Z. A., M. Nazhipkyzy, B. T. Lesbayev, N. G. Prikhodko, M. Auyelkhankyzy, and I. K. Puri. "Synthesis of Superhydrophobic Carbon Surface during Combustion Propane." Eurasian Chemico-Technological Journal 14, no. 1 (December 15, 2011): 19. http://dx.doi.org/10.18321/ectj94.

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We synthesize and deposit carbon nanostructures through flame synthesis on silicon and nickel wafers at different nonpremixed flame locations to produce hydrophobic surfaces. The hydrophobicity is characterized through the contact angle for water droplets placed on the surface. The surface morphology of the nanoparticles is obtained from SEM images. The morphology and hydrohobicity of the nanostructured surfaces depends upon the deposition, which differs at various flame locations. We determine the optimum flame location for the synthesis and deposition of surface carbon nanostructures that lead to maximum hydrophobicity.

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Spiecker, Erdmann, Stefan Hollensteiner, Wolfgang Jäger, Hans Haselier, and Herbert Schroeder. "Self-Assembled Nanostructures on VSe2Surfaces Induced by Cu Deposition." Microscopy and Microanalysis 11, no. 5 (September 28, 2005): 456–71. http://dx.doi.org/10.1017/s1431927605050373.

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Analytical transmission electron microscopy (TEM) and scanning electron microscopy (SEM) have been applied for the characterization of evolution, lateral arrangements, orientations, and the microscopic nature of nanostructures formed during the early stages of ultrahigh vacuum electron beam evaporation of Cu onto surfaces of VSe2layered crystals. Linear nanostructure of relatively large lateral dimension (100–500 nm) and networks of smaller nanostructures (lateral dimension: 15–30 nm; mesh sizes: 500–2000 nm) are subsequently formed on the substrate surfaces. Both types of nanostructures are not Cu nanowires but are composed of two strands of crystalline substrate material elevating above the substrate surface. For the large nanostructures a symmetric roof structure with an inclination angle of ∼30° with respect to the substrate surface could be deduced from detailed diffraction contrast experiments. In addition to the nanostructure networks a thin layer of a Cu-VSe2intercalation phase of 3R polytype is observed at the substrate surface. A dense network of interface dislocations indicates that the phase formation is accompanied by in-plane strain. We present a model that explains the formation of large and small nanostructures as consequences of compressive layer strains that are relaxed by the formation of rooflike nanostructures, finally evolving into the observed networks with increasing deposition time. The dominating contributions to the compressive layer strains are considered to be an electronic charge transfer from the Cu adsorbate to the substrate and the formation of a Cu-VSe2intercalation compound in a thin surface layer.

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Li, Xin, Yiming Guo, and Hai Cao. "Nanostructured surfaces from ligand-protected metal nanoparticles." Dalton Transactions 49, no. 41 (2020): 14314–19. http://dx.doi.org/10.1039/d0dt02822c.

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Ranjan, A., N. Pothayee, M. N. Seleem, N. Sriranganathan, R. Kasimanickam, M. Makris, and J. S. Riffle. "In Vitro Trafficking and Efficacy of Core-Shell Nanostructures for Treating Intracellular Salmonella Infections." Antimicrobial Agents and Chemotherapy 53, no. 9 (July 13, 2009): 3985–88. http://dx.doi.org/10.1128/aac.00009-09.

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ABSTRACT Nanostructures encapsulating gentamicin and having either amphiphilic (N1) or hydrophilic (N2) surfaces were designed. Flow cytometry and confocal microscopy studies demonstrated a higher rate of uptake for amphiphilic surfaces. A majority of N1 were localized in the cytoplasm, whereas N2 colocalized with the endosomes/lysosomes. Colocalization was not observed between nanostructures and intracellular Salmonella bacteria. However, significant in vitro reductions in bacterial counts (0.44 log10) were observed after incubation with N1, suggesting that the surface property of the nanostructure influences intracellular bacterial clearance.

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Mills, Christopher A., Elena Martinez, Abdelhamid Errachid, Elisabeth Engel, Miriam Funes, Christian Moormann, Thorsten Wahlbrink, Gabriel Gomila, Josep Planell, and Josep Samitier. "Nanoembossed Polymer Substrates for Biomedical Surface Interaction Studies." Journal of Nanoscience and Nanotechnology 7, no. 12 (December 1, 2007): 4588–94. http://dx.doi.org/10.1166/jnn.2007.18110.

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Biomedical devices are moving towards the incorporation of nanostructures to investigate the interactions of biological species with such topological surfaces found in nature. Good optical transparency and sealing properties, low fabrication cost, fast design realization times, and bio-compatibility make polymers excellent candidates for the production of surfaces containing such nanometric structures. In this work, a method for the production of nanostructures in free-standing sheets of different thermoplastic polymers is presented, with a view to using these substrates in biomedical cell-surface applications where optical microscopy techniques are required. The process conditions for the production of these structures in poly(methyl methacrylate), poly(ethylene naphthalate), poly(lactic acid), poly(styrene), and poly(ethyl ether ketone) are given. The fabrication method used is based on a modified nanoimprint lithography (NIL) technique using silicon based moulds, fabricated via reactive ion etching or focused ion beam lithography, to emboss nanostructures into the surface of the biologically compatible thermoplastic polymers. The method presented here is designed to faithfully replicate the nanostructures in the mould while maximising the mould lifetime. Examples of polymer replicas with nanostructures of different topographies are presented in poly(methyl methacrylate), including nanostructures for use in cell-surface interactions and nanostructure-containing microfluidic devices.

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10

Chen, Cheng-Ying, Ming-Wei Chen, Jr-Jian Ke, Chin-An Lin, José R. D. Retamal, and Jr-Hau He. "Surface effects on optical and electrical properties of ZnO nanostructures." Pure and Applied Chemistry 82, no. 11 (August 6, 2010): 2055–73. http://dx.doi.org/10.1351/pac-con-09-12-05.

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This article presents a comprehensive review of the current research addressing the surface effects on physical properties and potential applications of nanostructured ZnO. Studies illustrating the transport, photoluminescence (PL), and photoconductivity properties of ZnO with ultrahigh surface-to-volume (S/V) ratio are reviewed first. Secondly, we examine recent studies of the applications of nanostructured ZnO employing the surface effect on gas/chemical sensing, relying on a change of conductivity via electron trapping and detrapping process at the surfaces of nanostructures. Finally, we comprehensively review the photovoltaic (PV) application of ZnO nanostructures. The ultrahigh S/V ratios of nanostructured devices suggest that studies on the synthesis and PV properties of various nanostructured ZnO for dye-sensitized solar cells (DSSCs) offer great potential for high efficiency and low-cost solar cell solutions. After surveying the current literature on the surface effects on nano-structured ZnO, we conclude this review with personal perspectives on a few surface-related issues that remain to be addressed before nanostructured ZnO devices can reach their ultimate potential as a new class of industrial applications.

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Jaggessar, Alka, Asha Mathew, Tuquabo Tesfamichael, Hongxia Wang, Cheng Yan, and Prasad KDV Yarlagadda. "Bacteria Death and Osteoblast Metabolic Activity Correlated to Hydrothermally Synthesised TiO2 Surface Properties." Molecules 24, no. 7 (March 27, 2019): 1201. http://dx.doi.org/10.3390/molecules24071201.

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Orthopaedic surgery comes with an inherent risk of bacterial infection, prolonged antibiotic therapy and revision surgery. Recent research has focused on nanostructured surfaces to improve the bactericidal and osseointegrational properties of implants. However, an understanding of the mechanical properties of bactericidal materials is lacking. In this work, the surface properties of hydrothermal TiO2 nanostructured surfaces are investigated for their effect on bactericidal efficiency and cellular metabolic activity of human osteoblast cells. TiO2 nanostructures, approximately 307 nm in height and 14 GPa stiffness, were the most effective structures against both gram-positive (Staphylococcus aureus) and gram-negative (Pseudomonas aeruginosa) bacteria. Statistical analysis significantly correlated structure height to the death of both bacteria strains. In addition, the surface contact angle and Young’s modulus were correlated to osteoblast metabolic activity. Hydrophilic surfaces with a contact angle between 35 and 50° produced the highest cellular metabolic activity rates after 24 hours of incubation. The mechanical tests showed that nanostructures retain their mechanical stability and integrity over a long time-period, reaffirming the surfaces’ applicability for implants. This work provides a thorough examination of the surface, mechanical and wettability properties of multifunctional hydrothermally synthesised nanostructured materials, capable of killing bacteria whilst improving osteoblast metabolic rates, leading to improved osseointegration and antibacterial properties of orthopaedic implants.

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12

SHEN, MENGYAN. "NANOSTRUCTURING SOLID SURFACES WITH FEMTOSECOND LASER IRRADIATIONS FOR APPLICATIONS." Modern Physics Letters B 24, no. 03 (January 30, 2010): 257–69. http://dx.doi.org/10.1142/s0217984910022457.

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Pulsed laser-assisted etching is a simple but effective method for fabricating small regular structures directly onto a surface. We have successfully fabricated submicro- or nano-meter sized spikes on a solid surface immersed in liquids with femtosecond laser pulse irradiations. This method is applicable to different metals such as stainless steel, copper, titanium, cobalt, as well as different semiconductors, such as Si and GaAs. The femtosecond laser method is much faster than other methods. We can control the experimental conditions to design and fabricate nanostructures in different materials and on the surfaces with different morphologies. Here, we discuss the nanostructures formation with femtosecond pulse laser irradiations, and introduce our results of the nanostructure for applications in sensing, biology and artificial photosynthesis. The femtosecond laser irradiation technique can efficiently integrate metal, semiconductor and polymer nanostructures in various small devices to leverage the expertise in other research fields and applications.

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Chen, Yong, and Jiguo Zhang. "High-Speed Erosion Behavior of Hydrophobic Micro/Nanostructured Titanium Surfaces." Nanomaterials 12, no. 5 (March 7, 2022): 880. http://dx.doi.org/10.3390/nano12050880.

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Ice accretion on aircrafts or their engines can cause serious problems and even accidents. Traditional anti-icing and de-icing systems reduce engine efficiency, which can be improved by the use of hydrophobic/icephobic coatings or surfaces that reduce the amount of bleed air or electric power needed. These hydrophobic/icephobic coatings or surfaces are eroded by high-speed air flow, water droplets, ice crystals, sand, and volcanic ash, resulting in the degradation, material loss, or deterioration of the coating’s waterproof and anti-icing properties. Thus, the durability of hydrophobic micro/nanostructured surfaces is a major concern in aircraft applications. However, the mechanism responsible for material loss in hydrophobic micro/nanostructured surfaces resulting from high-speed erosion remains unclear. In this paper, hydrophobic titanium alloy surfaces with cubic pit arrays are fabricated by photoetching and tested using a high-speed sand erosion rig. Under the same impact conditions, the erosion rates of the micro/nanostructured titanium surfaces were similar to those of smooth titanium alloy, implying that the hydrophobic surface fabricated on the bulk material had erosion-resistant capabilities. The material loss mechanisms of the micro/nanostructures under different impact angles were compared, providing useful information for the future optimization of micro/nanostructures with the goal of improved erosion resistance.

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Geagea, Elie, Frank Palmino, and Frédéric Cherioux. "On-Surface Chemistry on Low-Reactive Surfaces." Chemistry 4, no. 3 (August 11, 2022): 796–810. http://dx.doi.org/10.3390/chemistry4030057.

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Zero-dimensional (0D), mono-dimensional (1D), or two-dimensional (2D) nanostructures with well-defined properties fabricated directly on surfaces are of growing interest. The fabrication of covalently bound nanostructures on non-metallic surfaces is very promising in terms of applications, but the lack of surface assistance during their synthesis is still a challenge to achieving the fabrication of large-scale and defect-free nanostructures. We discuss the state-of-the-art approaches recently developed in order to provide covalently bounded nanoarchitectures on passivated metallic surfaces, semiconductors, and insulators.

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Maghsoudi, Khosrow, Gelareh Momen, Reza Jafari, Masoud Farzaneh, and Tony Carreira. "Micro-Nanostructured Silicone Rubber Surfaces Using Compression Molding." Materials Science Forum 941 (December 2018): 1802–7. http://dx.doi.org/10.4028/www.scientific.net/msf.941.1802.

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A facile method is introduced for production of micro-nanostructured silicone rubber surfaces by means of direct replication using a compression molding system. The fabricated samples possessing surface roughness display water contact angle of more than 160o and contact angle hysteresis (CAH) and sliding angle of less than 5o. Such low surface wettability of silicone specimens verifies the induced superhydrophobic property. Chemically etched aluminum surfaces could work excellently as templates whose patterns were replicated on the rubber surfaces successfully. Various etching conditions were examined. Surface characterization techniques revealed the presence of micro-nanostructures on the produced silicone surfaces.

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Klos, Antoine, Xxx Sedao, Tatiana E. Itina, Clémentine Helfenstein-Didier, Christophe Donnet, Sylvie Peyroche, Laurence Vico, Alain Guignandon, and Virginie Dumas. "Ultrafast Laser Processing of Nanostructured Patterns for the Control of Cell Adhesion and Migration on Titanium Alloy." Nanomaterials 10, no. 5 (April 30, 2020): 864. http://dx.doi.org/10.3390/nano10050864.

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Femtosecond laser texturing is a promising surface functionalization technology to improve the integration and durability of dental and orthopedic implants. Four different surface topographies were obtained on titanium-6aluminum-4vanadium plates by varying laser processing parameters and strategies: surfaces presenting nanostructures such as laser-induced periodic surface structures (LIPSS) and ‘spikes’, associated or not with more complex multiscale geometries combining micro-pits, nanostructures and stretches of polished areas. After sterilization by heat treatment, LIPSS and spikes were characterized to be highly hydrophobic, whereas the original polished surfaces remained hydrophilic. Human mesenchymal stem cells (hMSCs) grown on simple nanostructured surfaces were found to spread less with an increased motility (velocity, acceleration, tortuosity), while on the complex surfaces, hMSCs decreased their migration when approaching the micro-pits and preferentially positioned their nucleus inside them. Moreover, focal adhesions of hMSCs were notably located on polished zones rather than on neighboring nanostructured areas where the protein adsorption was lower. All these observations indicated that hMSCs were spatially controlled and mechanically strained by the laser-induced topographies. The nanoscale structures influence surface wettability and protein adsorption and thus influence focal adhesions formation and finally induce shape-based mechanical constraints on cells, known to promote osteogenic differentiation.

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Iglesias-Juez, Ana, Francesc Viñes, Oriol Lamiel-García, Marcos Fernández-García, and Francesc Illas. "Morphology effects in photoactive ZnO nanostructures: photooxidative activity of polar surfaces." Journal of Materials Chemistry A 3, no. 16 (2015): 8782–92. http://dx.doi.org/10.1039/c5ta01111f.

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Microscopy and spectroscopy experiments combined with density functional calculations on ZnO nanostructures with variable morphology reveal the relationship between surface-related physicochemical properties and the nanostructure photochemical response.

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Culhane, Kyle, Ke Jiang, Aaron Neumann, and Anatoliy O. Pinchuk. "Laser-Fabricated Plasmonic Nanostructures for Surface-Enhanced Raman Spectroscopy of Bacteria Quorum Sensing Molecules." MRS Advances 2, no. 42 (2017): 2287–94. http://dx.doi.org/10.1557/adv.2017.98.

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ABSTRACTA laser deposition technique, based on the photo-reduction of silver ions from an aqueous solution, was used to fabricate silver nanostructure surfaces on glass cover slips. The resulting silver nanostructures exhibited plasmonic properties, which show promise in applications towards surface enhanced Raman spectroscopy (SERS). Using the standard thiophenol, the enhancement factor calculated for the deposits was approximately ∼106, which is comparable to other SERS-active plasmonic nanostructures fabricated through more complex techniques, such as electron beam lithography. The silver nanostructures were then employed in the enhancement of Raman signals from N-butyryl-L-homoserine lactone, a signaling molecule relevant to bacteria quorum sensing. In particular, the work presented herein shows that the laser-deposited plasmonic nanostructures are promising candidates for monitoring concentrations of signaling molecules within biofilms containing quorum sensing bacteria.

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Fernandes, Joshua, and Sangmo Kang. "Numerical Study on the Surface Plasmon Resonance Tunability of Spherical and Non-Spherical Core-Shell Dimer Nanostructures." Nanomaterials 11, no. 7 (June 30, 2021): 1728. http://dx.doi.org/10.3390/nano11071728.

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The near-field enhancement and localized surface plasmon resonance (LSPR) on the core-shell noble metal nanostructure surfaces are widely studied for various biomedical applications. However, the study of the optical properties of new plasmonic non-spherical nanostructures is less explored. This numerical study quantifies the optical properties of spherical and non-spherical (prolate and oblate) dimer nanostructures by introducing finite element modelling in COMSOL Multiphysics. The surface plasmon resonance peaks of gold nanostructures should be understood and controlled for use in biological applications such as photothermal therapy and drug delivery. In this study, we find that non-spherical prolate and oblate gold dimers give excellent tunability in a wide range of biological windows. The electromagnetic field enhancement and surface plasmon resonance peak can be tuned by varying the aspect ratio of non-spherical nanostructures, the refractive index of the surrounding medium, shell thickness, and the distance of separation between nanostructures. The absorption spectra exhibit considerably greater dependency on the aspect ratio and refractive index than the shell thickness and separation distance. These results may be essential for applying the spherical and non-spherical nanostructures to various absorption-based applications.

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Hong, J. I., F. T. Parker, V. C. Solomon, P. Madras, David J. Smith, and A. E. Berkowitz. "Fabrication of spherical particles with mixed amorphous/crystalline nanostructured cores and insulating oxide shells." Journal of Materials Research 23, no. 6 (June 2008): 1758–63. http://dx.doi.org/10.1557/jmr.2008.0199.

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By spark-eroding Fe75Si15B10 in water/ethanol mixtures, spherical particles with nanostructured cores consisting of mixed amorphous and crystalline phases were produced. The relative volume fractions of the amorphous and crystalline phases were dependent on the water/ethanol ratio. In the same process, continuous oxide layers were formed on the particle surfaces. The basic mechanisms responsible for the formation of the surface oxide layers and the core nanostructures were modeled. At frequencies ranging from 1 to 100 MHz, the combination of the core nanostructures and the insulating oxide shells yielded exceptionally low-loss magnetic behavior.

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Matei, Ecaterina, Carmen Gaidau, Maria Râpă, Laura Mihaela Stefan, Lia-Mara Ditu, Andra Mihaela Predescu, Maria Stanca, et al. "Sustainable Coated Nanostructures Based on Alginate and Electrospun Collagen Loaded with Antimicrobial Agents." Coatings 11, no. 2 (January 21, 2021): 121. http://dx.doi.org/10.3390/coatings11020121.

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In this study, sodium alginate film (Alg) was coated with electrospun collagen glue (Col) extracted from rabbit skin waste, loaded with different commercial antimicrobial agents (chitosan, AG425K and ZnONPs) and investigated in terms of morphological, structural and biological properties. The coated nanostructures were characterized using scanning electron microscopy coupled with the energy-dispersive X-ray (SEM/EDS), Attenuated Total Reflectance Fourier-Transform Infrared spectroscopy (ATR FT-IR), and Atomic Force Microscopy (AFM) tests. The cytotoxicity was investigated on murine L929 fibroblasts using 3-[4,5-dimethylthiazol-2-yl]-2,5-diphenyltetrazolium bromide salt (MTT) and lactate dehydrogenase (LDH) assays. Microbiological tests were performed against Staphylococcus aureus ATCC 25923, Escherichia coli ATCC 25922, Pseudomonas aeruginosa ATCC 27853 and Candida albicans ATCC 27853 standard strains. In vitro cell culture tests showed a good cytocompatibility of the coated nanostructured systems, except the sample loaded with ZnONPs, which exhibited a highly cytotoxic effect. Alg-Col-ZnONPs nanostructure inhibited the growth and multiplication of the Staphylococcus aureus ATCC 25923 and Escherichia coli ATCC 25922 bacterial strains. The results of new coated nanostructures may be useful for the development of sustainable biomaterials in a circular economy, with bioactive properties for medical wound dressings.

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Huang, Hanchen, and Helena Van Swygenhoven. "Atomistic Simulations of Mechanics of Nanostructures." MRS Bulletin 34, no. 3 (March 2009): 160–66. http://dx.doi.org/10.1557/mrs2009.46.

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AbstractNanostructures can be in the form of nanoparticles or nanograins, nanowires or nanotubes, and nanoplates or multilayers. These nanostructures may be used individually or embedded in a bulk material. In both cases, they share two common features. First, the small dimensions minimize or even eliminate the presence of defects. Second, nanostructures entail large surface or interface areas. The absence of defects makes nanostructure materials stronger than their bulk counterparts, leading to the eventual realization of ideal strength. The presence of surfaces and interfaces may either reduce or increase the strength. Atomistic simulations can provide insight into the deformation mechanism at the atomic and electronic level, something that is very difficult to obtain from experiments. This article describes generic features of nanostructures and summarizes the five areas presented in the articles in this issue.

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Lu, Xizhao, Lei Kang, Binggong Yan, Tingping Lei, Gaofeng Zheng, Haihe Xie, Jingjing Sun, and Kaiyong Jiang. "Evolution of a Superhydrophobic H59 Brass Surface by Using Laser Texturing via Post Thermal Annealing." Micromachines 11, no. 12 (November 29, 2020): 1057. http://dx.doi.org/10.3390/mi11121057.

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To fabricate an industrial and highly efficient super-hydrophobic brass surface, annealed H59 brass samples have here been textured by using a 1064 nm wavelength nanosecond fiber laser. The effects of different laser parameters (such as laser fluence, scanning speed, and repetition frequency), on the translation to super-hydrophobic surfaces, have been of special interest to study. As a result of these studies, hydrophobic properties, with larger water contact angles (WCA), were observed to appear faster than for samples that had not been heat-treated (after an evolution time of 4 days). This wettability transition, as well as the evolution of surface texture and nanograins, were caused by thermal annealing treatments, in combination with laser texturing. At first, the H59 brass samples were annealed in a Muffle furnace at temperatures of 350 °C, 600 °C, and 800 °C. As a result of these treatments, there were rapid formations of coarse surface morphologies, containing particles of both micro/nano-level dimensions, as well as enlarged distances between the laser-induced grooves. A large number of nanograins were formed on the brass metal surfaces, onto which an increased number of exceedingly small nanoparticles were attached. This combination of fine nanoparticles, with a scattered distribution of nanograins, created a hierarchic Lotus leaf-like morphology containing both micro-and nanostructured material (i.e., micro/nanostructured material). Furthermore, the distances between the nano-clusters and the size of nano-grains were observed, analyzed, and strongly coupled to the wettability transition time. Hence, the formation and evolution of functional groups on the brass surfaces were influenced by the micro/nanostructure formations on the surfaces. As a direct consequence, the surface energies became reduced, which affected the speed of the wettability transition—which became enhanced. The micro/nanostructures on the H59 brass surfaces were analyzed by using Field Emission Scanning Electron Microscopy (FESEM). The chemical compositions of these surfaces were characterized by using an Energy Dispersive Analysis System (EDS). In addition to the wettability, the surface energy was thereby analyzed with respect to the different surface micro/nanostructures as well as to the roughness characteristics. This study has provided a facile method (with an experimental proof thereof) by which it is possible to construct textured H59 brass surfaces with tunable wetting behaviors. It is also expected that these results will effectively extend the industrial applications of brass material.

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Li, Zhaohui, Congqin Ning, Dongyan Ding, Hegang Liu, and Lin Huang. "Biological Properties of Ti-Nb-Zr-O Nanostructures Grown on Ti35Nb5Zr Alloy." Journal of Nanomaterials 2012 (2012): 1–7. http://dx.doi.org/10.1155/2012/834042.

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Surface modification of low modulus implant alloys with oxide nanostructures is one of the important ways to achieve favorable biological behaviors. In the present work, amorphous Ti-Nb-Zr-O nanostructures were grown on a peak-aged Ti35Nb5Zr alloy through anodization. Biological properties of the Ti-Nb-Zr-O nanostructures were investigated throughin vitrobioactivity testings, stem cell interactions, and drug release experiments. The Ti-Nb-Zr-O nanostructures demonstrated a good capability of inducing apatite formation after immersion in simulated body fluids (SBFs). Drug delivery experiment based on gentamicin and the Ti-Nb-Zr-O nanostructures indicated that a high drug loading content could result in a prolonged release process and a higher quantity of drug residues in the oxide nanostructures after drug release. Quick stem cell adhesion and spreading, as well as fast formation of extracellular matrix materials on the surfaces of the Ti-Nb-Zr-O nanostructures, were found. These findings make it possible to further explore the biomedical applications of the Ti-Nb-Zr-O nanostructure modified alloys especially clinical operation of orthopaedics by utilizing the nanostructures-based drug-release system.

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Gong, Jiang Feng, Wei Hua Zhu, Kai Xiao Zhang, Ming Yi Liu, and Hai Yan Xie. "Synthesis Aligned ZnS Nanocone and its Photoluminescence." Advanced Materials Research 295-297 (July 2011): 610–13. http://dx.doi.org/10.4028/www.scientific.net/amr.295-297.610.

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We report the synthesis and characterization of ZnS nanostructures, which were grown by thermal evaporation of the ZnS powder at high temperature using iron network as the collection substrate. Scanning electron microscopy investigations show that the products present taper-like morphologies. Transmission electron microscopy studies indicate ZnS nanostructures are well crystallized. The formation mechanism of the novel nanostructure is discussed on the basis of the experimental results; The nanostructure is formed due to a fast growth of ZnS nanowire along [0001] and the subsequent “epitaxial” radial growth of the ZnS nanocone along the six (01-10) surfaces around the nanowire. A strong room-temperature photoluminescence in ZnS nanostructures has been demonstrated.

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Qin, Ge, Hao Xue Li, Meng Die Ma, Juan Juan Li, and Ya Fei Deng. "Cell Growth Morphology on Nano-Structured Surface Based on Wetting." Advanced Materials Research 1061-1062 (December 2014): 575–78. http://dx.doi.org/10.4028/www.scientific.net/amr.1061-1062.575.

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This paper studied the growth morphology of the cells on the nanostructured surfaces of the bio-electrodes implanted in human patients. A transition model of the cells on those surfaces, which is the W model or C-B model, was deduced according to the effect of the microstructures on the wetting characteristics and the solid-liquid contact angle models of the microstructured surface. According to the contact angle formula of the model of the droplet on the solid surface, the formula was derived to describe the morphology of the ells on the nanostructured surface. The results of the experiments showed the impact of nanostructured to the morphology of the cells. The changes of the cell morphology on the smooth surface and the nanostructured surface showed that the cell morphology was affected by the nanostructures of solid surface, and the growth shape of cell was different when the sizes were different.

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Wang, Guilin, Ronghua Yi, Xueting Zhai, Renji Bian, Yongqian Gao, Dongyu Cai, Juqing Liu, et al. "A flexible SERS-active film for studying the effect of non-metallic nanostructures on Raman enhancement." Nanoscale 10, no. 35 (2018): 16895–901. http://dx.doi.org/10.1039/c8nr04971h.

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Seyghalkar, Hamideh, Mohammad Sabet, and Masoud Salavati-Niasari. "Simple Thermal Decompose Method for Synthesis of Nickel Disulfide Nanostructures." High Temperature Materials and Processes 35, no. 10 (November 1, 2016): 1017–19. http://dx.doi.org/10.1515/htmp-2015-0169.

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AbstractIn this work, a simple thermal decompose method was served to synthesize NiS2 nanostructures via a nickel complex. Also polyethylene glycol (PEG) was used as surfactant to increase the steric effect around nanostructure surfaces and decrease the particles size. The product was characterized with different analysis methods. The crystal structure of the product was studied by X-ray diffraction (XRD) pattern. The particle size and morphology were investigated by scanning electron microscopy (SEM). To study the nanostructures surface purity, Fourier transform infrared spectroscopy (FT-IR) was used. And finally to study the optical properties of the product photoluminescence (PL) spectroscopy was served.

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Doll, P. W., M. Wolf, M. Weichert, R. Ahrens, A. E. Guber, and B. Spindler. "Nanostructuring of Titanium by Anodic Oxidation with Sulfuric and Hydrofluoric Acid." Current Directions in Biomedical Engineering 4, no. 1 (September 1, 2018): 641–44. http://dx.doi.org/10.1515/cdbme-2018-0154.

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AbstractWithin this work we demonstrate different Anodic Oxidation processes to achieve a broad variety of nanostructures on titanium and the titanium alloy Ti6Al4V for the use as medical implant surfaces. The influence of electrolyte, reaction time and voltage on the nanostructure formation is described as well as the transfer to microstructured surfaces. As electrolytes we investigate sulfuric and hydrofluoric acids with different concentrations. The resulting nanostructures reach from nano porosities over amorphous sponge like structures to self-assembled hexagonal nanotubes.

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Chan, Shook Pui, Diane S. W. Lim, Arunmozhiarasi Armugam, Guangshun Yi, and Yugen Zhang. "Soft Surface Nanostructure with Semi-Free Polyionic Components for Sustainable Antimicrobial Plastic." International Journal of Molecular Sciences 22, no. 22 (November 15, 2021): 12315. http://dx.doi.org/10.3390/ijms222212315.

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Surface antimicrobial materials are of interest as they can combat the critical threat of microbial contamination without contributing to issues of environmental contamination and the development drug resistance. Most nanostructured surfaces are prepared by post fabrication modifications and actively release antimicrobial agents. These properties limit the potential applications of nanostructured materials on flexible surfaces. Here, we report on an easily synthesized plastic material with inherent antimicrobial activity, demonstrating excellent microbicidal properties against common bacteria and fungus. The plastic material did not release antimicrobial components as they were anchored to the polymer chains via strong covalent bonds. Time-kill kinetics studies have shown that bactericidal effects take place when bacteria come into contact with a material for a prolonged period, resulting in the deformation and rupture of bacteria cells. A scanning probe microscopy analysis revealed soft nanostructures on the submicron scale, for which the formation is thought to occur via surface phase separation. These soft nanostructures allow for polyionic antimicrobial components to be present on the surface, where they freely interact with and kill microbes. Overall, the new green and sustainable plastic is easily synthesized and demonstrates inherent and long-lasting activity without toxic chemical leaching.

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Yakimchuk, Dzmitry V., Victoria D. Bundyukova, Jon Ustarroz, Herman Terryn, Kitty Baert, Artem L. Kozlovskiy, Maxim V. Zdorovets, et al. "Morphology and Microstructure Evolution of Gold Nanostructures in the Limited Volume Porous Matrices." Sensors 20, no. 16 (August 6, 2020): 4397. http://dx.doi.org/10.3390/s20164397.

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The modern development of nanotechnology requires the discovery of simple approaches that ensure the controlled formation of functional nanostructures with a predetermined morphology. One of the simplest approaches is the self-assembly of nanostructures. The widespread implementation of self-assembly is limited by the complexity of controlled processes in a large volume where, due to the temperature, ion concentration, and other thermodynamics factors, local changes in diffusion-limited processes may occur, leading to unexpected nanostructure growth. The easiest ways to control the diffusion-limited processes are spatial limitation and localized growth of nanostructures in a porous matrix. In this paper, we propose to apply the method of controlled self-assembly of gold nanostructures in a limited pore volume of a silicon oxide matrix with submicron pore sizes. A detailed study of achieved gold nanostructures’ morphology, microstructure, and surface composition at different formation stages is carried out to understand the peculiarities of realized nanostructures. Based on the obtained results, a mechanism for the growth of gold nanostructures in a limited volume, which can be used for the controlled formation of nanostructures with a predetermined geometry and composition, has been proposed. The results observed in the present study can be useful for the design of plasmonic-active surfaces for surface-enhanced Raman spectroscopy-based detection of ultra-low concentration of different chemical or biological analytes, where the size of the localized gold nanostructures is comparable with the spot area of the focused laser beam.

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Dies, Hannah, Adam Bottomley, Danielle Lilly Nicholls, Kevin Stamplecoskie, Carlos Escobedo, and Aristides Docoslis. "Electrokinetically-Driven Assembly of Gold Colloids into Nanostructures for Surface-Enhanced Raman Scattering." Nanomaterials 10, no. 4 (April 2, 2020): 661. http://dx.doi.org/10.3390/nano10040661.

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Surface-enhanced Raman scattering (SERS) enables the highly sensitive detection of (bio)chemical analytes in fluid samples; however, its application requires nanostructured gold/silver substrates, which presents a significant technical challenge. Here, we develop and apply a novel method for producing gold nanostructures for SERS application via the alternating current (AC) electrokinetic assembly of gold nanoparticles into two intricate and frequency-dependent structures: (1) nanowires, and (2) branched “nanotrees”, that create extended sensing surfaces. We find that the growth of these nanostructures depends strongly on the parameters of the applied AC electric field (frequency and voltage) and ionic composition, specifically the electrical conductivity of the fluid. We demonstrate the sensing capabilities of these gold nanostructures via the chemical detection of rhodamine 6G, a Raman dye, and thiram, a toxic pesticide. Finally, we demonstrate how these SERS-active nanostructures can also be used as a concentration amplification device that can electrokinetically attract and specifically capture an analyte (here, streptavidin) onto the detection site.

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LI, WEI, ZHONGPING WANG, XINLI LENG, YAN LU, XIAOQING LIU, and LI WANG. "ORGANOMETALLIC NANOSTRUCTURES OF 1,4-DIBROMO-2,5-DIIODOBENZENE BY METAL IONS CONSTRUCTION ON HOPG SURFACE." Surface Review and Letters 23, no. 04 (June 15, 2016): 1650020. http://dx.doi.org/10.1142/s0218625x16500207.

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Different organometallic nanostructures on highly oriented pyrolytic graphite (HOPG) have been synthesized by different metal ions coordinating with 1,4-Dibromo-2,5-diiodobenzene (C6H2Br2I2). Scanning tunneling microscopy (STM) images directly demonstrated the transformation of the nanostructure from self-assembled nanostructures formed by C6H2Br2I2 through halogen bond into organometallic network, formed by the dehalogenated C6H2Br2I2 molecules covalent bonded with metal ions. Moreover, by varying the concentrations of C6H2Br2I2 molecules or valence states of metal ions, organometallic structures with different shapes and sizes have been fabricated, which illustrates that the concentrations and valence states of the metal ions play important roles in the organometallic nanostructures.

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Бутко, А. В., В. Ю. Бутко, and Ю. А. Кумзеров. "Зависимость подвижности носителей заряда в гибридных наноструктурах на интерфейсе графена с молекулярными ионами от их зарядовой плотности." Физика твердого тела 63, no. 11 (2021): 1960. http://dx.doi.org/10.21883/ftt.2021.11.51603.141.

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A.V. Butko, V.Y. Butko, Y.A.Kumzerov Ioffe Institute, 194021, St. Petersburg, Russia Hybrid nanostructures with large interface between nanostructural elements play an important role in the modern electronics. Among these nanostructures are hybrid nanostructures formed at the interface of graphene with ensembles of molecular ions in the solution gated Graphene Field Effect Transistors (GFETs) that are promising for chemical and biological sensor fabrication. Therefore investigation of interfacial effects in electrical transport in these systems is interesting. This work is a theoretical study of dependence of the charge carrier mobility (µ) in these nanostructures on density of the interfacial molecular ions (Nii). We show that dependence µ~1/(Nii)^1/2 obtained in free charge carrier model with short range scattering in case of the weak interaction between the charge carriers and the interfacial ions is in agreement with experimental transistor characteristics obtained at the high gate voltages.

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Disch, Alexander, Jörg Mick, Benedikt Bläsi, and Claas Müller. "Nanostructures on microstructured surfaces." Microsystem Technologies 13, no. 5-6 (May 30, 2006): 483–86. http://dx.doi.org/10.1007/s00542-006-0191-2.

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Широкий, Юрій Вячеславович, Юрій Олександрович Сисоєв, and Тетяна Олександрівна Постельник. "Моделювання умов отримання наноструктур в алюмінієвих сплавах при дії іонізуючого випромінювання." Aerospace technic and technology, no. 2 (April 25, 2022): 55–63. http://dx.doi.org/10.32620/aktt.2022.2.07.

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The use of laser radiation as a source of ionizing radiation to obtain nanostructured and submicrostructured layers on aluminum alloys requires the determination of the necessary technological parameters. Therefore, a theoretical study of ionizing radiation on aluminum alloy AK8 was conducted according to the previously proposed model. When choosing the region in the material of the aluminum alloy, where nanostructures can be formed under the action of ionizing radiation, apply different lengths of ions. Because of the theoretical study of the formation of nanostructures in the surface layer of the aluminum alloy AK8, the temperature distribution in the zone of ionizing radiation at different depths of the material was obtained. Temperature fields for different heat flux densities q1 = 106 W/m2 and q2 = 105 W/m2 were also constructed. The obtained temperature fields for heat flux q1 showed that with increasing depth of the material, the temperature decreases from 2480 to 650 K. The values of maximum temperatures on the material surface are slightly higher than necessary to obtain nanostructures at lower depths maximum temperatures decrease to nanostructures can be realized. Simultaneously, under the action of heat flux q2 = 105 W/m2, the maximum surface temperature decreased to values of 1950 K, and at depth it was 550 K. and was equal to 106 K/s at q2. All these confirmed the possibility of creating conditions for the formation of nanostructures. Due to the temperature range obtained from the calculated temperature fields, the depths of the aluminum alloy where nanostructures can be formed were determined. Studies of the effect of laser radiation spot size on the surface of the material on the formation of nanostructures were also conducted, which showed that when exposed to a spot size of 3 · 103 to 10-3 m, the possibility of nanostructures is significantly reduced, while reducing the spot size to 10-4 m leads to a significant increase in the possibility of forming nanostructures. To estimate the possible volume of nanostructures, the dependence of the nanocluster size on the heat flux density in the range from 107 to 1010 W / m2 and its action time in the range from 10-9 to 10-3 s were considered. The dependence of the maximum temperature on the heat flux density and the time of its action is also constructed. All this allows you to choose the technological parameters of laser radiation to obtain nanostructured layers on aluminum alloys, and the ability to determine the size of nanostructures allows you to predict the physical and mechanical characteristics of the surface layers of processing materials. These studies may be of interest to specialists in strengthening the surfaces of aluminum alloys and further studies of nanostructures.

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Wu, Jinshuang, Mingzhao Ouyang, Bowei Yang, and Yuegang Fu. "Simulation of Mushroom Nanostructures with Ag Nanoparticles for Broadband and Wide-Angle Superabsorption." Coatings 12, no. 8 (August 18, 2022): 1208. http://dx.doi.org/10.3390/coatings12081208.

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Metal nanoparticles (NPs) concentrate the energy of incident photons through plasmon resonance excitation, which allows scattering into a substrate with a high refractive index, and the radiated energy from this excitation significantly increases the optical absorption of the substrate. In this work, the effect of Ag NPs on the absorption capacity of mushroom-nanostructured Si metasurfaces was analyzed using the finite-difference time-domain method. It was observed that the absorbance in the metasurfaces with Ag NPs increased from 90.8% to 98.7% compared with nanostructured Si metasurface without NPs. It was shown that the plasmon resonance effect of Ag NPs enlarged the range of the FP cavity by about 10 times, and the electric field strength E2 increased by about four times through the combination of Ag NP and Si absorbers. Meanwhile, the effect of randomly distributed nanostructures on the absorption properties of Si metasurfaces was simulated. Additionally, the nanostructured surface with Ag NPs was insensitive to angle, which encourages the design of broadband and wide-angle superabsorption nanostructures.

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Shang, Lina, Faming Kang, Wenze Gao, Zheng Zhou, and Wei Xu. "On-Surface Synthesis of sp-Carbon Nanostructures." Nanomaterials 12, no. 1 (December 31, 2021): 137. http://dx.doi.org/10.3390/nano12010137.

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The on-surface synthesis of carbon nanostructures has attracted tremendous attention owing to their unique properties and numerous applications in various fields. With the extensive development of scanning tunneling microscope (STM) and noncontact atomic force microscope (nc-AFM), the on-surface fabricated nanostructures so far can be characterized on atomic and even single-bond level. Therefore, various novel low-dimensional carbon nanostructures, challenging to traditional solution chemistry, have been widely studied on surfaces, such as polycyclic aromatic hydrocarbons, graphene nanoribbons, nanoporous graphene, and graphyne/graphdiyne-like nanostructures. In particular, nanostructures containing sp-hybridized carbons are of great advantage for their structural linearity and small steric demands as well as intriguing electronic and mechanical properties. Herein, the recent developments of low-dimensional sp-carbon nanostructures fabricated on surfaces will be summarized and discussed.

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Kaur, Gurjinder, Amlan Baishya, R. Manoj Kumar, Debrupa Lahiri, and Indranil Lahiri. "Distinct Levels of Adhesion Energy of In-Situ Grown CuO Nanostructures." Journal of Nanoscience and Nanotechnology 20, no. 6 (June 1, 2020): 3527–34. http://dx.doi.org/10.1166/jnn.2020.17419.

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CuO nanostructures were reported for a myriad of applications in diverse areas such as high Tc superconductors, field emitters, catalysts, gas sensors, magnetic storage, biosensors, superhydrophobic surfaces, energy materials etc. In all these applications, structural stability of the nanostructures is very important for efficient functioning of devices with a longer lifetime. Hence, it is necessary to understand the adhesion energy of these nanostructures with their substrates. In this research work, a variety of CuO nanostructures were synthesized directly on Cu foil substrate by varying only the concentration of the reagents. CuO nanostructures, thus grown, were subjected to a nano-scratch test to quantify their adhesion strength with Cu substrate. The adhesion energy was observed to be highest for nanorods and lowest for nanoribbons among all the CuO nanostructures synthesized in this work. Results of this research will be useful in predicting the service life and in improving the efficiency of CuO nanostructure-based devices.

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BELHADI, M., A. KHATER, and K. MASCHKE. "TRANSMISSION OF PHONON MODES IN QUASI-ONE-DIMENSIONAL WAVEGUIDES VIA DOUBLE L-SHAPED JOINT NANOSTRUCTURES." Surface Review and Letters 11, no. 01 (February 2004): 87–97. http://dx.doi.org/10.1142/s0218625x04005950.

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The influence of a special class of atomic nanostructures embedded on a waveguide is analyzed for the scattering and transmission of elastic waves in quasi-one-dimensional multicanal waveguides. The quasi-one-dimensional waveguide is constructed of double chains of atoms, and the nanostructures consist of geometrical configurations, where the double chains are arranged to form several types of double L-shaped joints. Numerical results are presented for the three types of nanostructures, using the matching method. The theoretical approach allows us to calculate the reflection and the transmission probabilities as well as the average phonon conductance of the system along the waveguide. The results show that the transmission probabilities and the average conductance depend strongly on the type of geometrical joint nanostructure. The pronounced fluctuations in the transmission and conductance spectra as a function of the frequency can be understood as Fano resonances that result from the coherent coupling between the propagating modes and the localized vibrational modes induced by the nanostructures.

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Bertel, Linda, David A. Miranda, and José Miguel García-Martín. "Nanostructured Titanium Dioxide Surfaces for Electrochemical Biosensing." Sensors 21, no. 18 (September 14, 2021): 6167. http://dx.doi.org/10.3390/s21186167.

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TiO2 electrochemical biosensors represent an option for biomolecules recognition associated with diseases, food or environmental contaminants, drug interactions and related topics. The relevance of TiO2 biosensors is due to the high selectivity and sensitivity that can be achieved. The development of electrochemical biosensors based on nanostructured TiO2 surfaces requires knowing the signal extracted from them and its relationship with the properties of the transducer, such as the crystalline phase, the roughness and the morphology of the TiO2 nanostructures. Using relevant literature published in the last decade, an overview of TiO2 based biosensors is here provided. First, the principal fabrication methods of nanostructured TiO2 surfaces are presented and their properties are briefly described. Secondly, the different detection techniques and representative examples of their applications are provided. Finally, the functionalization strategies with biomolecules are discussed. This work could contribute as a reference for the design of electrochemical biosensors based on nanostructured TiO2 surfaces, considering the detection technique and the experimental electrochemical conditions needed for a specific analyte.

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LU, MAO-WANG. "SPIN POLARIZATION OF ELECTRONS BY DEPOSITING HYBRID FERROMAGNETIC STRIPES ON A SEMICONDUCTOR HETEROSTRUCTURE." Surface Review and Letters 11, no. 03 (June 2004): 331–35. http://dx.doi.org/10.1142/s0218625x04006220.

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One type of combined magnetically modulated nanostructures is proposed that can be experimentally realized by depositing two hybrid ferromagnetic stripes on the surface of a semiconductor heterostructure. Since these two stripes induce different magnetic barriers, the electron transmission and the conductance of nanostructure are strongly dependent upon the electronic spins. Thus, in this kind of hybrid magnetic nanostructures, electrons show up a considerable spin polarization effect, which provides an alternative approach to realization of spin-polarized electrons into semiconductors and may be of practical importance for spin-based nanodevice applications.

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Saji, Viswanathan S. "Carbon nanostructure-based superhydrophobic surfaces and coatings." Nanotechnology Reviews 10, no. 1 (January 1, 2021): 518–71. http://dx.doi.org/10.1515/ntrev-2021-0039.

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Abstract Research and development on superhydrophobic carbon nanostructures and their nanocomposites have high industrial significance. Here, a comprehensive review of the topic is provided. Reported works on superhydrophobic surfaces and coatings of carbon nanotubes, nanofibres, nanospheres/nanothorns/others, nanodiamond, fullerene and their various nanocomposites with metals, ceramics, and polymers are described. Superhydrophobic nanostructured carbon soot, graphitic carbon, and others are also presented. The section on superhydrophobic graphene is presented concisely at the end. Reports in different application areas, including anti-corrosion, anti-icing, oil separation, anti-biofouling, and sensors, are discussed separately. Superoleophobic and superamphiphobic surfaces are also discussed.

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Basioli, Lovro, Krešimir Salamon, Marija Tkalčević, Igor Mekterović, Sigrid Bernstorff, and Maja Mičetić. "Application of GISAXS in the Investigation of Three-Dimensional Lattices of Nanostructures." Crystals 9, no. 9 (September 13, 2019): 479. http://dx.doi.org/10.3390/cryst9090479.

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The application of the grazing-incidence small-angle X-ray scattering (GISAXS) technique for the investigation of three-dimensional lattices of nanostructures is demonstrated. A successful analysis of three-dimensionally ordered nanostructures requires applying a suitable model for the description of the nanostructure ordering. Otherwise, it is possible to get a good agreement between the experimental and the simulated data, but the parameters obtained by fitting may be completely incorrect. In this paper, we theoretically examine systems having different types of nanostructure ordering, and we show how the choice of the correct model for the description of ordering influences the analysis results. Several theoretical models are compared in order to show how to use GISAXS in the investigation of self-assembled arrays of nanoparticles, and also in arrays of nanostructures obtained by ion-beam treatment of thin films or surfaces. All models are supported by experimental data, and the possibilities and limitations of GISAXS for the determination of material structure are discussed.

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Movafaghi, S., W. Wang, A. Metzger, D. D. Williams, J. D. Williams, and A. K. Kota. "Tunable superomniphobic surfaces for sorting droplets by surface tension." Lab on a Chip 16, no. 17 (2016): 3204–9. http://dx.doi.org/10.1039/c6lc00673f.

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Yan, Ningzhe, Hao Luo, Yanan Liu, Haiping Yu, and Guangyin Jing. "Motility Suppression and Trapping Bacteria by ZnO Nanostructures." Crystals 12, no. 8 (July 23, 2022): 1027. http://dx.doi.org/10.3390/cryst12081027.

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Regulating the swimming motility of bacteria near surfaces is essential to suppress or avoid bacterial contamination and infection in catheters and medical devices with wall surfaces. However, the motility of bacteria near walls strongly depends on the combination of the local physicochemical properties of the surfaces. To unravel how nanostructures and their local chemical microenvironment dynamically affect the bacterial motility near surfaces, here, we directly visualize the bacterial swimming and systematically analyze the motility of Escherichia coli swimming on ZnO nanoparticle films and nanowire arrays with further ultraviolet irradiation. The results show that the ZnO nanowire arrays reduce the swimming motility, thus significantly enhancing the trapping ability for motile bacteria. Additionally, thanks to the wide bandgap nature of a ZnO semiconductor, the ultraviolet irradiation rapidly reduces the bacteria locomotion due to the hydroxyl and singlet oxygen produced by the photodynamic effects of ZnO nanowire arrays in an aqueous solution. The findings quantitatively reveal how the combination of geometrical nanostructured surfaces and local tuning of the steric microenvironment are able to regulate the motility of swimming bacteria and suggest the efficient inhibition of bacterial translocation and infection by nanostructured coatings.

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Vinnikov, N. A., A. V. Dolbin, and M. V. Khlistyuck. "Hydrogen sorption by nanostructures at low temperatures (Review article)." Low Temperature Physics 49, no. 5 (May 1, 2023): 507. http://dx.doi.org/10.1063/10.0017811.

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The features of hydrogen sorption by a wide range of nanostructures — fullerite C60, carbon nanotubes, graphene structures, nanodispersed carbon, including Pd-containing nanoclusters, ordered silicon-oxide-based nanostructures (the MCM-41 family) and silicon-oxide aerogel — have been reviewed. Special attention is given to the sorption characteristics of carbon nanostructures that have been exposed to various modifying treatments (oxidation, gamma-ray irradiation in gas atmosphere, action of pulsed high frequency gas discharge). Two mechanisms of physical low-temperature sorption of hydrogen have been revealed to predominate in such nanostructures in different temperature intervals. At the lowest temperatures (8–12 K), the sorption can actually proceed without thermal activation: it is realized through the tunnel motion of hydrogen molecules along the nanostructure surfaces. The periodic structure of the potential relief, allowed by the surface frame of carbon and silicon-oxide nanostructures, along the rather low interpit barriers are beneficial for the formation of low-dimensional (including quantum) hydrogen-molecule systems practically without thermally activated diffusion. In such nanostructures, the hydrogen diffusion coefficients are actually independent of temperature at 8–12 K. At higher temperatures (12–295 K), a thermally activated mechanism of hydrogen diffusion prevails. The periodic structure of fullerite C60 contains periodic interstitial cavities, separated by rather low potential barriers. Their sizes are sufficient to accommodate impurity hydrogen molecules and, thus, allow diffusion processes, which can also have a tunnel nature. It is shown that gamma-irradiation and high-frequency gas discharge processing increase markedly the quantity of hydrogen strongly bonded to carbon nanostructures.

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Matringe, Caroline, Elsa Thune, René Guinebretière, and David Babonneau. "Self-ordering on vicinal surfaces studied by 3D GISAXS measurements." Acta Crystallographica Section A Foundations and Advances 70, a1 (August 5, 2014): C879. http://dx.doi.org/10.1107/s2053273314091207.

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Nanostructured systems made of islands deposited onto oxide surfaces have both fundamental and technological interests and are used in the field of electronic, linear or non-linear optic, and optoelectronic. The final properties of these systems depend on the shape and the size of nanoparticles and also on their organization. On this general framework, we aim at producing self-organized nanostructures using vicinal surfaces [1],[2]. Vicinal surfaces are obtained by cutting a single crystal with a small deviation of the surface normal with respect to a crystallographic plane leading to a surface with terraces separated by steps. Suitable templates for the growth of self-organized nanostructures are created thanks to the re-arrangement of the steps during thermal treatment (step bunching). Different types of nanostructured surfaces can be elaborated and used as templates since the substrates exhibit a one-dimensional (1D) or two-dimensional (2D) periodic patterns (fig. 1a). The surface morphology and the periodicity can be tuned with the thermal treatment parameters (i.e. annealing time, temperature and atmosphere) and also with the sample parameters (i.e. miscut and azimuthal angles). Ordered stepped oxide surfaces are characterized ex-situ after each treatment on a laboratory scale by Atomic Force Microscopy (AFM), which provide a direct image of the surface morphology (step height, step curvature, terrace width...) over a small probed area (a few µm2). Quantitative analysis of the surface morphology has been studied by grazing incidence small angle scattering using a specific set-up implemented recently onto the BM02 beamline at ESRF (Grenoble, France). Prior to the SAXS measurements, the samples were strictly oriented according to the primary beam direction using a 3-axis sample holder. 3D reciprocal space maps around the (000) node were then recorded onto a 2D pixel detector through 3600rotation of the samples around the azimuthal angle. Modelling of 2D sections of the (000) reciprocal space node were realized using the FitGISAXS software [3]. Typical experimental and calculated maps are reported fig. 1b and 1c. We demonstrate that the 2D ordered surface is consistent with a rectangular centred periodic lattice decorated by truncated tetrahedrons (see fig. 1d).

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Mugarza, A., F. Schiller, J. Kuntze, J. Cordón, M. Ruiz-Osés, and J. E. Ortega. "Modelling nanostructures with vicinal surfaces." Journal of Physics: Condensed Matter 18, no. 13 (March 13, 2006): S27—S49. http://dx.doi.org/10.1088/0953-8984/18/13/s03.

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Goniakowski, Jacek, and Claudine Noguera. "Insulating oxide surfaces and nanostructures." Comptes Rendus Physique 17, no. 3-4 (March 2016): 471–80. http://dx.doi.org/10.1016/j.crhy.2015.12.007.

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Journal articles on the topic 'Nanostructures - Surfaces'

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