Journal articles: 'Nanoporous'

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Sa, Na, Sue-Sin Chong, Hui-Qiong Wang, and Jin-Cheng Zheng. "Anisotropy Engineering of ZnO Nanoporous Frameworks: A Lattice Dynamics Simulation." Nanomaterials 12, no. 18 (September 18, 2022): 3239. http://dx.doi.org/10.3390/nano12183239.

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The anisotropy engineering of nanoporous zinc oxide (ZnO) frameworks has been performed by lattice dynamics simulation. A series of zinc oxide (ZnO) nanoporous framework structures was designed by creating nanopores with different sizes and shapes. We examined the size effects of varying several features of the nanoporous framework (namely, the removal of layers of atoms, surface-area-to-volume ratio, coordination number, porosity, and density) on its mechanical properties (including bulk modulus, Young’s modulus, elastic constant, and Poisson ratio) with both lattice dynamics simulations. We also found that the anisotropy of nanoporous framework can be drastically tuned by changing the shape of nanopores. The maximum anisotropy (defined by Ymax/Ymin) of the Young’s modulus value increases from 1.2 for bulk ZnO to 2.5 for hexagon-prism-shaped ZnO nanoporous framework structures, with a density of 2.72 g/cm3, and, even more remarkably, to 89.8 for a diamond-prism-shape at a density of 1.72 g/cm3. Our findings suggest a new route for desirable anisotropy and mechanical property engineering with nanoporous frameworks by editing the shapes of the nanopores for the desired anisotropy.

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Her, Hyun Jung, Jung Min Kim, Yun Soo Lim, Jae Wan Kim, Y. J. Choi, C. J. Kang, and Yong Sang Kim. "Nanoporous Titania by Embossing with PMMA Nanopoles Made from Nanoporous Alumina Template." Materials Science Forum 544-545 (May 2007): 1017–20. http://dx.doi.org/10.4028/www.scientific.net/msf.544-545.1017.

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We produced highly uniform nanoporous thin films of the dense array of titania (TiO2) pores of 70~80 nm in diameter with nanoimprinting method. Titania in HCl and 2-propanol solution was coated on an indium tin oxide (ITO) surface and embossed with an array of PMMA nanopoles which was produced using a nanoporous alumina (Al2O3) template. Two-step anodization was introduced to produce highly uniform and dense nanopores on the aluminum surface. The polymethyl methacrylate (PMMA) was poured onto and infiltrated into the nanoporous alumina surface which was heated at 150 oC. The alumina nanopores and aluminum plate were removed by wet-etching leaving an array of PMMA nanopoles. These highly uniform nanostructured titania films will be very useful for photovoltaic and photocatalytic applications where nanostructuring of surface with controlled dimensions are essential.

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Chou, Chia-Man, Tong-You Wade Wei, Jou-May Maureen Chen, Wei-Ting Chang, Chang-Tze Ricky Yu, and Vincent K. S. Hsiao. "Preparation of Nanoporous Polymer Films for Real-Time Viability Monitoring of Cells." Journal of Nanomaterials 2011 (2011): 1–6. http://dx.doi.org/10.1155/2011/436528.

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We have demonstrated an alternative way to monitor the viability of cells adhered on a nanoporous polymer film in real time. The nanoporous polymer films were prepared by laser interference pattering. During exposure of holographic patterning, the dissolved solvents were phase separated with photocured polymer and the nanopores were created as the solvents evaporated. The diffracted spectra from the nanoporous polymer film responded to each activity of the cell cycle, from initial cell seeding, through growth, and eventual cell death. This cell-based biosensor uses a nanoporous polymer film to noninvasively monitor cell viability and may prove useful for biotechnological applications.

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MO, YANG, and TAN FEI. "NANOPOROUS MEMBRANE FOR BIOSENSING APPLICATIONS." Nano LIFE 02, no. 01 (March 2012): 1230003. http://dx.doi.org/10.1142/s1793984411000323.

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Synthetic nanoporous membranes have been used in numerous biosensing applications, such as glucose detection, nucleic acid detection, bacteria detection, and cell-based sensing. The increased surface affinity area and enhanced output sensing signals make the nanoporous membranes increasingly attractive as biosensing platforms. Surface modification techniques can be used to improve surface properties for realizable bioanalyte immobilization, conjugation, and detection. Combined with realizable detection techniques such as electrochemical and optical detection methods, nanoporous membrane–based biosensors have advantages, including rapid response, high sensitivity, and low cost. In this paper, an overview of nanoporous membranes for biosensing application is given. Types of nanoporous membranes including polymer membranes, inorganic membranes, membranes with nanopores fabricated using nanolithography, and nanotube-based membranes are introduced. The fabrication techniques of nanoporous membranes are also discussed. The key requirements of nanoporous membranes for biosensing applications include surface functionality for bioanalyte immobilization, biocompatibility, mechanical and chemical stability, and anti-biofouling capability. The recent advances and development of nanoporous membrane–based biosensors are discussed, especially for the sensing mechanism and surface functionalization strategies. Finally, the challenges and future development of nanoporous membrane for biosensing applications are discussed.

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Petryk, Mykhaylo, and Dmytro Mykhalyk. "High-performance intellectual information technologies for the study of filtration systems in different-sized nanoporous particles media." Scientific journal of the Ternopil national technical university 108, no. 4 (2022): 16–26. http://dx.doi.org/10.33108/visnyk_tntu2022.04.016.

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In the paper, the technologies for the high-performance intellectual nanoporous filtration systems based on the mathematical model of the two-level transport «filtration-consolidation» in the system of nanopores in two intraparticle spaces, which includes two subspaces of different-sized nanoporous particles are developed.

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Nasr Esfahani, Mohammad, and Masoud Jabbari. "Molecular Dynamics Simulations of Deformation Mechanisms in the Mechanical Response of Nanoporous Gold." Materials 13, no. 9 (April 30, 2020): 2071. http://dx.doi.org/10.3390/ma13092071.

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The mechanical behaviour of nanoporous gold has so far been the subject of studies for bicontinuous morphologies, while the load transfer between ligaments is the primary challenge for using nanoporous structures—especially membranes with nanopores—in single-molecule sensors. This work studies the pore shape effect on deformation mechanisms of nanoporous gold membranes through molecular dynamics simulations. Tension and compression tests are carried out for nanoporous gold with circular, elliptical, square and hexagonal pore shapes. A significant pore shape effect on the mechanical properties is observed with distinct load transfer capabilities. A uniform stress transfer between ligaments constitutes a distinguished set of mechanical responses for structures with the hexagonal pore shape under tension, while a unique stress distribution in nanoporous with the circular pore shape introduces a high strength and ductile structure under compression. Further to shed light on the existing experimental observations, this work provides a comprehensive study on load transfer capabilities in the mechanical behaviour of nanoporous gold for sensing applications.

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Tsunekane, Masafumi, Kyosuke Yoshimi, and Kouichi Maruyama. "Attempt to Control Spatial Distribution of Nano-Gold Particles Using Nanoporous Surfaces of FeAl Single Crystal." Advanced Materials Research 26-28 (October 2007): 185–88. http://dx.doi.org/10.4028/www.scientific.net/amr.26-28.185.

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In this study, the distribution of colloidal nano-gold particles on the nanoporous surfaces of FeAl single crystals was investigated. Colloidal nano-gold particles were dropped onto the nanoporous surface, and their distribution was observed by TEM. Some of nano-gold particles located at the edges of nanopores. A few additional attempts to improve the wettability of the surfaces were made using surface treatments. As a result, the frequency of nano-gold particles put into nanopores was achieved up to 98.3%.

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Suciu, Claudiu Valentin, and Shuuhei Fukui. "Rheological Model for a Nanoporous-Elasto-Hydrodynamic Composite Material." Materials Science Forum 750 (March 2013): 100–103. http://dx.doi.org/10.4028/www.scientific.net/msf.750.100.

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This work proposes a rheological model for a nanoporous-elasto-hydrodynamic composite material (NPEHDCM), which can be obtained by mixing a colloid, consisted of water and water-repellent nanoporous silica micro-particles, with an adequate jellification agent. Hydrogel is modeled as a biphasic mixture consisted of a nanoporous hydrophilic isotropic and linear elastic solid matrix, and a liquid phase (water). At dynamic pressurization, water molecules exude from the hydrogel matrix and forcedly penetrate the nanopores of hydrophobic silica particles. Based on the proposed rheological model, the NPEHDCM can be suitably designed.

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Brüggemann, Dorothea. "Nanoporous Aluminium Oxide Membranes as Cell Interfaces." Journal of Nanomaterials 2013 (2013): 1–18. http://dx.doi.org/10.1155/2013/460870.

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Nanoporous anodic aluminium oxide (AAO) has become increasingly important in biomedical applications over the past years due to its biocompatibility, increased surface area, and the possibility to tailor this nanomaterial with a wide range of surface modifications. AAO nanopores are formed in an inexpensive anodisation process of pure aluminium, which results in the self-assembly of highly ordered, vertical nanochannels with well-controllable pore diameters, depths, and interpore distances. Because of these outstanding properties AAO nanopores have become excellent candidates as nanostructured substrates for cell-interface studies. In this comprehensive review previous surveys on cell adhesion and proliferation on different AAO nanopore geometries and surface modifications are highlighted and summarised tabularly. Future applications of nanoporous alumina membranes in biotechnology and medicine are also outlined, for instance, the use of nanoporous AAO as implant modifications, coculture substrates, or immunoisolation devices.

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Wang, Ya, Hai Wang, and Wei Wan. "The Incorporation of Carbon Element into Nanoporous Anodic Alumina by Pulse Anodization." Journal of Nanoscience and Nanotechnology 19, no. 6 (June 1, 2019): 3621–26. http://dx.doi.org/10.1166/jnn.2019.16126.

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The incorporation of carbon element into nanoporous anodic aluminum oxides from oxalic acid electrolyte was studied. The carbon element content in nanoporous anodic alumina by pulse anodization reaches up to ∼20 at.%, while it remains ∼7 at.% under constant anodization. It was proposed that the ionic dynamics in nanopores governs the carbon-containing anions incorporation into nanoporous anodic oxides. For the same 20 V resting voltage, the content of carbon element remains unchanged in a broad range of working voltages: 40–150 V. X-ray photoelectron analysis further revealed that the sp2/sp3 and C–O/C═O ratios increased significantly as the working voltage increased. The color exhibited by the nanoporous anodic alumina was related to the chemical states of the carbon present in the alumina, and not the carbon content.

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Yin, Linjie, Xingyao Yin, and Kun Li. "Rock physics model for shale gas reservoirs with nanopore adsorption." Journal of Geophysics and Engineering 19, no. 5 (September 20, 2022): 1012–27. http://dx.doi.org/10.1093/jge/gxac065.

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Abstract Shale gas is primarily concentrated in nanopores extensively distributed in shale. The elastic properties of nanopores are significantly different from those of pores of larger sizes due to surface effects. How nanopores and adsorbed fluids affect the overall elastic properties of rock is rarely studied. Based on a recently developed nano-elasticity theory, a new method for calculating elastic modulus of nanoporous media considering adsorption is proposed by performing a detailed analysis on the relationship of surface adsorption with surface effects. The surface parameters of nanopores (pore radius, surface elastic moduli) are converted to adsorbed gas ratio and adsorbed gas elastic moduli. The proposed method is then used in rock physics modeling to estimate the elastic properties of nanoporous shale. The quantitative relationships of the effective velocities with adsorbed gas ratio, adsorbed gas elastic modulus and porosity of the shale are established, respectively. An important finding is that the elastic properties of nanoporous shale can be enhanced by increasing adsorbed gas ratio and adsorbed gas elastic moduli. A comparison between the theoretical model with laboratory data and the well data is performed and the results indicate that they are in good agreement. The results in this paper may provide certain insights on rock physics for the quantitative characterization of elastic properties of shale.

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Hieda, Junko, Mitsuo Niinomi, Masaaki Nakai, Ken Cho, Tomoyoshi Mohri, and Takao Hanawa. "Biomedical Polymer Surface Modification of Beta-Type Titanium Alloy for Implants through Anodic Oxide Nanostructures." Materials Science Forum 783-786 (May 2014): 1261–64. http://dx.doi.org/10.4028/www.scientific.net/msf.783-786.1261.

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Anodic oxide nanostructures (nanopores and nanotubes) were formed on a biomedical β-type titanium alloy, Ti–29Nb–13Ta–4.6Zr alloy (TNTZ), in order to improve adhesive strength by the anchor effect of a segmented polyurethane (SPU) with soft tissue compatibility. The nanotube structure was formed beneath the nanoporous structure. The adhesive strength between the SPU coating and the nanoporous structure formed on TNTZ by anodization is more than 1.5 times that of an SPU coating on as-polished TNTZ with a mirror finish. After removal of the nanoporous structure by etching with HF solution, the adhesive strength of the SPU coating on the exposed nanotube structure is decreased.

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Ndaya, Dennis, Reuben Bosire, Lalit Mahajan, Scarlet Huh, and Rajeswari Kasi. "Synthesis of ordered, functional, robust nanoporous membranes from liquid crystalline brush-like triblock copolymers." Polymer Chemistry 9, no. 12 (2018): 1404–11. http://dx.doi.org/10.1039/c7py02127e.

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Shishkina A. S., Yandybaeva Y. I., Yakimuk V.A., Alsaif Y., Zakoldaev R. A., and Andreeva O. V. "Direct Laser Writing and Investigation of Optofluidic Elements inside Nanoporous Silicate Matrix." Optics and Spectroscopy 130, no. 5 (2022): 625. http://dx.doi.org/10.21883/eos.2022.05.54450.2885-21.

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The paper demonstrates direct laser writing by femtosecond laser pulses (λ = 1030 nm, tau = 220 fs, v = 200 kHz) of functional optofluidic elements inside a nanoporous silicate matrix (NPSM). The influence of focused laser pulses led to the compaction of the nanoporous frame, which made it possible to fabricate barriers for the isolation of nanoporous cells and channel optical waveguides. The writing of microchannels in the mode of decompression of a nanoporous matrix with subsequent purification of debris area in distilled water under the action of ultrasound is also demonstrated. For each type of elements, the dependences of geometric characteristics on the energy parameters of laser radiation are established. The methods of testing the elements were also developed --- checking the permeability of the barrier, the entering of laser radiation into channel waveguides. Keywords: Direct laser writing, femtosecond laser pulses, barriers, waveguide, microchannel, porous silicate matrix, nanopores.

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Guo, Linfan, Haibin Tang, Xiujuan Wang, Yupeng Yuan, and Chuhong Zhu. "Nanoporous Ag-Decorated Ag7O8NO3 Micro-Pyramids for Sensitive Surface-Enhanced Raman Scattering Detection." Chemosensors 10, no. 12 (December 16, 2022): 539. http://dx.doi.org/10.3390/chemosensors10120539.

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Porous noble metal nanomaterials can be employed to construct sensitive surface-enhanced Raman scattering (SERS) substrates, because the plasmonic nanopores and nanogaps of the porous materials can provide a larger number of hotspots, and can also serve as containers of analyte molecules. However, the fabrication processes of nanoporous noble metal are generally complicated. Here, a facile method is presented to prepare nanoporous Ag nanoparticles-decorated Ag7O8NO3 micro-pyramids, which are fabricated through the chemical reduction of the electrodeposited Ag7O8NO3 micro-pyramids using NaBH4. The Ag7O8NO3 micro-pyramids are fabricated by electrodeposition by using a simple aqueous solution of AgNO3 as electrolyte. Then, porous Ag-decorated Ag7O8NO3 micro-pyramids are achieved by the chemical reduction of the surface of the electrodeposited Ag7O8NO3 micro-pyramids with NaBH4. The high-density nanopores and nanogaps of the fabricated nanoporous Ag can provide plenty of hot spots for Raman enhancement. Additionally, the nanopores have an effective capacity to trap and enrich analytes. Using rhodamine 6G (R6G) as a probe molecule, the SERS performance of the fabricated SERS substrate has been investigated. It is found that a limit of detection (LOD) ~1.0 × 10−15 M can be achieved for R6G. Then, the SERS substrates are employed to detect dye molecule (crystal violet) and pesticide (thiram), and their LODs are calculated down to 9.6 × 10−13 M and 1.3 × 10−15 M, respectively. The enhancement factor of the fabricated SERS substrate is estimated to be as high as 5.6 × 108. Therefore, the nanoporous Ag-decorated Ag7O8NO3 micro-pyramids have shown promising application in the sensitive SERS detection of organic molecules.

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Rodrigues, Elisa Marchezini, Ronald Arreguy Silva, and Maximiliano Delany Martins. "ESTUDO DA PREPARAÇÃO E DA MORFOLOGIA DE SUPERFÍCIE DE ALUMINA NANOPOROSA AUTO-ORGANIZADA." e-xacta 6, no. 2 (November 30, 2013): 61. http://dx.doi.org/10.18674/exacta.v6i2.1071.

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A alumina nanoporosa é um material que apresenta nanocanais auto-ordenados espontaneamente em formato hexagonal. Produzida a partir da anodização do alumínio metálico, vem sendo usada como molde para produção de materiais em escala nanométrica. Este trabalho teve como objetivo o estudo da preparação e a caracterização morfológica da alumina nanoporosa auto-organizada. A alumina nanoporosa foi preparada seguindo-se a metodologia proposta por Masuda e Fukuda (1995), um método de dois passos de anodização que consiste em anodizar a amostra de alumínio, remover a camada de óxido de alumínio (alumina) formada e, em seguida, repetir o processo de anodização, sob as mesmas condições da primeira. Este procedimento resulta em alumina com poros de dimensão na faixa de dezenas de nanômetros, com estreita distribuição de tamanhos e com alto grau de ordenação.AbstractNanoporous alumina is a typical material that exhibits self-ordered nanochannels spontaneously organized in hexagonal shape. Produced by anodizing of metallic aluminum, it has been used as a template for production of materials at the nanoscale. This work aimed to study the preparation of nanoporous alumina by anodic anodizing of metallic aluminum substrates. The nanoporous alumina was prepared following the methodology proposed by Masuda and Fukuda (1995), a two-step method consisting of anodizing the aluminum sample in the potentiostatic mode, removing the layer of aluminum oxide (alumina) formed and then repeat the anodization process under the same conditions as the first anodization. This method produces nanoporous alumina with narrow pore diameter distribution and well-ordered structure.

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Tang, Xiao Peng, Lan Xu, Hong Ying Liu, and Na Si. "Fabrication of PLA Nanoporous Fibers by DMF/CF Mixed Solvent via Electrospinning." Advanced Materials Research 941-944 (June 2014): 400–403. http://dx.doi.org/10.4028/www.scientific.net/amr.941-944.400.

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Electrospinning represents a simple and convenient method for generating polymer fibers has been widely applied to produce porous nanofibers. The PLA fibers obtained in this research showed a significant nanoporous surface by varying solvent compositions of chloroform (CF) and N,N-dimethylformamide (DMF).The nanopores produced by phase separation of solvent system were observed by means of scanning electron microscope.The approach showed the fabrication of electrospun nanoporous fibers possessing ultrahigh specific surface area without any post-treatment.

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Slepchenkov, Michael M., Dmitry S. Shmygin, Gang Zhang, and Olga E. Glukhova. "Controlling the electronic properties of 2D/3D pillared graphene and glass-like carbon via metal atom doping." Nanoscale 11, no. 35 (2019): 16414–27. http://dx.doi.org/10.1039/c9nr05185f.

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Lijing, Zhong, Roman A. Zakoldaev, Maksim M. Sergeev, and Vadim P. Veiko. "Fluorescent Bulk Waveguide Sensor in Porous Glass: Concept, Fabrication, and Testing." Nanomaterials 10, no. 11 (October 30, 2020): 2169. http://dx.doi.org/10.3390/nano10112169.

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In this work, we suggest the new concept of sensing elements—bulk waveguides (BWGs) fabricated by the laser direct writing technique inside porous glass (PG). BWGs in nanoporous materials are promising to be applied in the photonics and sensors industries. Such light-guiding components interrogate the internal conditions of nanoporous materials and are able to detect chemical or physical reactions occurring inside nanopores especially with small molecules, which represent a separate class for sensing technologies. After the writing step, PG plates are impregnated with the indicator—rhodamine 6G—which penetrates through the nanoporous framework to the BWG cladding. The experimental investigation proved the concept by measuring the spectral characteristics of an output signal. We have demonstrated that the BWG is sensitive to ethanol molecules captured by the nanoporous framework. The sensitivity of the peak shift in the fluorescence spectrum to the refractive index of the solution is quantified as 6250 ± 150 nm/RIU.

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Lee, Seunghyeok, Sung-Jin Jung, Gwang Min Park, Seung-Hyub Baek, Heesuk Kim, Jin-Sang Kim, Tae Joo Park, and Seong Keun Kim. "ALD-Based Interface Engineering for Improving Electrical Conductivity of Nanoporous Thermoelectric Materials." ECS Meeting Abstracts MA2023-02, no. 29 (December 22, 2023): 1491. http://dx.doi.org/10.1149/ma2023-02291491mtgabs.

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The way to improve the performance of thermoelectric materials is to break the strong correlation between electrical conductivity and thermal conductivity. Combining porous structures with atomic layer deposition (ALD) is a promising strategy to solve this problem. The porous structure introduced into thermoelectric materials effectively lowers the lattice thermal conductivity, greatly increasing performance. However, the formation of nanopores is accompanied by a decrease in electrical conductivity. Here, we create nanoporous Bi0.4Sb1.6Te3 powder formed through selective dissolution from the mixture of KCl and Bi0.4Sb1.6Te3 powder. We propose a strategy to control carrier concentration by ALD of ZnO on nanoporous Bi0.4Sb1.6Te3 powder, thereby improving electrical conductivity and lowering thermal conductivity. Even after spark plasma sintering, ZnO is conformally formed at the nanoporous Bi0.4Sb1.6Te3 grain boundaries. The electrical conductivity increases from 651.72 S/cm to 724.52 S/cm by interfacial reaction of ZnO and Bi0.4Sb1.6Te3. In addition, ZnO inhibits grain growth and creates numerous grain boundaries to lower the lattice thermal conductivity of the porous structure. As a result, the ZT of the nanoporous Bi0.4Sb1.6Te3 deposited with ZnO is increased by 46%. This study demonstrates that ALD is an effective method for improving the conductivity of nanoporous thermoelectric materials.

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Gao, Yuan, Mingzhe Li, Yue Zhang, Weiyi Lu, and Baoxing Xu. "Spontaneous outflow efficiency of confined liquid in hydrophobic nanopores." Proceedings of the National Academy of Sciences 117, no. 41 (September 28, 2020): 25246–53. http://dx.doi.org/10.1073/pnas.2009310117.

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The suspension of nanoporous particles in a nonwetting liquid provides a unique solution to the crux of superfluid, sensing, and energy conversion, yet is challenged by the incomplete outflow of intruded liquid out of nanopores for the system reusability. We report that a continuous and spontaneous liquid outflow from hydrophobic nanopores with high and stable efficiency can be achieved by regulating the confinement of solid–liquid interactions with functionalized nanopores or/and liquids. Full-scale molecular-dynamics simulations reveal that the grafted silyl chains on nanopore wall surfaces will promote the hydrophobic confinement of liquid molecules and facilitate the molecular outflow; by contrast, the introduction of ions in the liquid weakens the hydrophobic confinement and congests the molecular outflow. Both one-step and multistep well-designed quasistatic compression experiments on a series of nanopores/nonwetting liquid material systems have been performed, and the results confirm the outflow mechanism in remarkable agreement with simulations. This study offers a fundamental understanding of the outflow of confined liquid from hydrophobic nanopores, potentially useful for devising emerging nanoporous-liquid functional systems with reliable and robust reusability.

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Sharma, Bharat Bhushan, and Avinash Parashar. "Mechanical strength of a nanoporous bicrystalline h-BN nanomembrane in a water submerged state." Physical Chemistry Chemical Physics 22, no. 36 (2020): 20453–65. http://dx.doi.org/10.1039/d0cp03235b.

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Mechanical strength of nanoporous single crystalline h-BN nanosheets deteriorates with an increase in the number of nanopores, whereas a contrasting trend was observed with bicrystalline h-BN nanosheets.

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Lei, Gang, Qinzhuo Liao, Weiqing Chen, Chunhua Lu, and Xianmin Zhou. "An Analytical Model for Hysteretic Pressure-Sensitive Permeability of Nanoporous Media." Nanomaterials 12, no. 23 (November 28, 2022): 4234. http://dx.doi.org/10.3390/nano12234234.

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Hysteretic pressure-sensitive permeability of nanohybrids composed of substantial nanopores is critical to characterizing fluid flow through nanoporous media. Due to the nanoscale effect (gas slippage), complex and heterogeneous pore structures of nanoporous media, the essential controls on permeability hysteresis of nanohybrids are not determined. In this study, a hysteretic pressure sensitive permeability model for nitrogen flow through dry nanoporous media is proposed. The derived model takes into account the nanoscale effect and pore deformation due to effective stress. The model is validated by comparing it with the experimental data. The results show that the calculated permeability and porosity are consistent with the measured results with the maximum relative error of 6.08% and 0.5%, respectively. Moreover, the hysteretic pressure-sensitive permeability of nanohybrids is related to effective stress, gas slippage, pore microstructure parameters, grain quadrilateral angle, and the loss rate of grain quadrilateral angle. The nanoscale effect is crucial to the permeability of nanoporous media. In addition, as impacted by the comprehensive impact of multiple relevant influential parameters, permeability during the pressure unloading process is not a monotonous function but presents complicated shapes. The proposed model can explain, quantify, and predict the permeability hysteresis effect of nanoporous media reasonably well.

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BRUNO, MARIANO M., HORACIO R. CORTI, JUAN BALACH, N. GUSTAVO COTELLA, and CESAR A. BARBERO. "HIERARCHICAL POROUS MATERIALS: CAPILLARIES IN NANOPOROUS CARBON." Functional Materials Letters 02, no. 03 (September 2009): 135–38. http://dx.doi.org/10.1142/s1793604709000685.

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A hierarchical carbon material containing nanopores (micropores and mesopores) and micrometric sized capillaries (macropores) is produced using a combination of hard and soft templates. The hard template is a polypropylene (PP) cloth which decomposes during pyrolysis leaving a macroporous structure. The soft template is a cationic polyelectrolyte which stabilizes the resorcinol/formaldehyde (RF) resin porous structure during drying to give a nanoporous RF resin. The method produces a nanocomposite of the porous RF resin with an imbibed PP cloth. The composite is then pyrolyzed in a inert gas atmosphere to render a carbon material having macropores as well as micro/mesopores. The material exhibits both a large surface area ( S BET = 742 ± 2 m 2/ g ) due to nanopores and goof fluid permeability due to micrometric sized pores. The macropores can be oriented during fabrication. The nanoporous surface can be used to support metal nanoparticles for fuel cell while the macropores allow easy flux of gas and liquids through the monolithic material.

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Benetti, Giulio, Francesco Banfi, Emanuele Cavaliere, and Luca Gavioli. "Mechanical Properties of Nanoporous Metallic Ultrathin Films: A Paradigmatic Case." Nanomaterials 11, no. 11 (November 18, 2021): 3116. http://dx.doi.org/10.3390/nano11113116.

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Nanoporous ultrathin films, constituted by a slab less than 100 nm thick and a certain void volume fraction provided by nanopores, are emerging as a new class of systems with a wide range of possible applications, including electrochemistry, energy storage, gas sensing and supercapacitors. The film porosity and morphology strongly affect nanoporous films mechanical properties, the knowledge of which is fundamental for designing films for specific applications. To unveil the relationships among the morphology, structure and mechanical response, a comprehensive and non-destructive investigation of a model system was sought. In this review, we examined the paradigmatic case of a nanoporous, granular, metallic ultrathin film with comprehensive bottom-up and top-down approaches, both experimentals and theoreticals. The granular film was made of Ag nanoparticles deposited by gas-phase synthesis, thus providing a solvent-free and ultrapure nanoporous system at room temperature. The results, bearing generality beyond the specific model system, are discussed for several applications specific to the morphological and mechanical properties of the investigated films, including bendable electronics, membrane separation and nanofluidic sensing.

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Yu, Yang-Yen, and Chang-Chung Yang. "Preparation of Nanoporous Poly(Methyl Silsesquioxanes) Films Using PS-b-P4VP as Template." Journal of Nanoscience and Nanotechnology 8, no. 3 (March 1, 2008): 1537–44. http://dx.doi.org/10.1166/jnn.2008.073.

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Nanoporous poly(methyl silsesquioxane) (PMSSQ) film was prepared through the templating of an amphiphilic block copolymer, poly(styrene-4-vinyl pyridine) (PS-b-P4VP). The experimental and theoretical studies suggest that the intermolecular hydrogen bonding is existed between the PMSSQ precursor and PS-b-P4VP. The miscible hybrid and the narrow thermal decomposition of the PS-b-P4VP lead to nanopores in the prepared films from the results of TGA, AFM, and TEM. The effects of the loading ratio on the morphology and properties of the prepared nanoporous PMSSQ films were investigated. The TEM and AFM studies show that the uniform pore morphology with pore size 10–15 nm can be prepared from a modest porogen loading level for the optimum intermolecular hydrogen bonding. The refractive index and dielectric constant of the prepared nanoporous films decreases with an increase in PS-b-P4VP loading. On the other hand, the porosity increases with an increasing PS-b-P4VP loading. This study demonstrates a methodology to control pore morphology and properties of the nanoporous PMSSQ films through the templating of PS-b-P4VP.

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Liu, Fujian, Weiping Kong, Liang Wang, Xianfeng Yi, Iman Noshadi, Anmin Zheng, and Chenze Qi. "Efficient biomass transformations catalyzed by graphene-like nanoporous carbons functionalized with strong acid ionic liquids and sulfonic groups." Green Chemistry 17, no. 1 (2015): 480–89. http://dx.doi.org/10.1039/c4gc01052c.

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Strong acid ionic liquids and sulfonic group bifunctional graphene-like nanoporous carbons with abundant nanopores, controlled acidity and excellent catalytic activity for biomass transformation have been successfully prepared in this work.

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28

Li, Mingzhe, and Weiyi Lu. "Adaptive liquid flow behavior in 3D nanopores." Physical Chemistry Chemical Physics 19, no. 26 (2017): 17167–72. http://dx.doi.org/10.1039/c7cp02981k.

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We have developed a novel liquid nanofoam (LN) system composed of nanoporous silica gel particles and a non-wettable liquid phase, which demonstrates the adaptive liquid flow behavior in 3D nanopores.

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29

Murzin, Serguei P., Alexander A. Igolkin, and Luiza F. Musaakhunova. "Creation of Submicroporous and Nanoporous Structures in Metallic Materials by Laser Thermocycling as Eutectic Is Reached." Advanced Materials Research 1088 (February 2015): 245–49. http://dx.doi.org/10.4028/www.scientific.net/amr.1088.245.

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The possibilities of forming submicroporous and nanoporous structures in metallic materials by laser thermocycling as eutecticis reached were determined. With the implementation of the selected modes of laser treatment on L62 brass samples with a thickness of 50 µm leads to the formation of wrinkled relief, which indicates an increment of alloy volume in this area, that is, a porosity increment in the metallic material. Submicroporous and nanoporous structures are formed in the copper-zinc L62 alloy sample, which appear on the surface of the sample. Nanopores have a shape similar to equiaxial. Submicropores are formed as a result of nanopores merger. A relief is formed on the surface consisting of depressions having a shape similar to that of a hemisphere and a linear structure, oriented along the direction of rolling process.

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30

Yang, Zhipeng, Jun Li, Panmei Liu, An Zhang, Jing Wang, Yuan Huang, Jiangyong Wang, and Zumin Wang. "Highly sensitive non-enzymatic hydrogen peroxide monitoring platform based on nanoporous gold via a modified solid-phase reaction method." RSC Advances 11, no. 58 (2021): 36753–59. http://dx.doi.org/10.1039/d1ra03184h.

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Ge/Au/Ge triple-layered precursor was proposed to prepare nanoporous gold (NPG) with much smaller grain sizes and nanopores as an electrochemical sensor for highly sensitive and selective detection of hydrogen peroxide.

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31

Vahdat, Mohammad Tohidi, Davide Campi, Nicola Colonna, Luis Francisco Villalobos, Nicola Marzari, and Kumar Varoon Agrawal. "Efficient Kr/Xe separation from triangular g-C3N4 nanopores, a simulation study." Journal of Materials Chemistry A 8, no. 34 (2020): 17747–55. http://dx.doi.org/10.1039/d0ta03071f.

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Poly(triazine imide) or PTI is a promising material for separation of ⁸⁵Kr/Xe mixture, thanks to its atom-thick nanoporous structure hosting triangular-shaped nanopores of ∼0.34 nm diameter.

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32

Wang, Sien, Qiyu Chen, and Qing Hao. "Extension of the two-layer model to heat transfer coefficient predictions of nanoporous Si thin films." Applied Physics Letters 121, no. 1 (July 4, 2022): 012201. http://dx.doi.org/10.1063/5.0099312.

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Heat exchange between a solid material and the gas environment is critical for the heat dissipation of miniature electronic devices. In this aspect, existing experimental studies focus on non-porous structures such as solid thin films, nanotubes, and wires. In this work, the proposed two-layer model for the heat transfer coefficient (HTC) between a solid sample and the surrounding air is extended to 70-nm-thick nanoporous Si thin films that are patterned with periodic rectangular nanopores having feature sizes of 100–400 nm. The HTC values are extracted using the 3[Formula: see text] method based on AC self-heating of a suspended sample with better accuracy than steady-state measurements in some studies. The dominance of air conduction in the measured HTCs is confirmed by comparing measurements with varied sample orientations. The two-layer model, developed for nanotubes, is still found to be accurate when the nanoporous film is simply treated as a solid film in the HTC evaluation along with the radiative mean beam length as the characteristic length of the nanoporous film. This finding indicates the potential of increasing HTC by introducing ultra-fine nanoporous patterns, as guided by the two-layer model.

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33

Yu, Yang Yen, Wen Chen Chien, and Shih Ting Chen. "Preparation of Nanoporous Mondispersed Silica Nanoparticles Films Using Poly(styrene)- Block-Poly( 2-Vinyl Pyridine) as Template." Advanced Materials Research 47-50 (June 2008): 646–49. http://dx.doi.org/10.4028/www.scientific.net/amr.47-50.646.

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Nanoporous silica films were prepared through the templating of amphiphilic block copolymer, poly(styrene-2-vinyl pyridine) (PS-b-P2VP), and colloidal silica nanoparticles. The experimental and theoretical studies suggested that the intermolecular hydrogen bonding was existed between the colloidal silica nanoparticles and PS-b-P2VP. The miscible hybrid and the narrow thermal decomposition of the PS-b-P2VP led to nanopores in the prepared films from the results of TGA, AFM, and TEM. The effects of the loading ratio and P2VP chain length on the morphology and properties of the prepared nanoporous silica films were investigated. The TEM and AFM studies showed that the uniform pore morphology with pore size 10-15nm was prepared from a modest porogen loading level for the optimum intermolecular hydrogen bonding. The refractive index and dielectric constant of the prepared nanoporous films decreased with an increase in PS-b-P2VP loading. On the other hand, the porosity increased with an increasing PS-b-P2VP loading. This study demonstrated a methodology to control pore morphology and properties of the nanoporous silica films through the templating of PS-b-P2VP.

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34

Sun, Hai-Xiang, Bing-Bing Yuan, Peng Li, Tao Wang, and Yan-Yan Xu. "Preparation of nanoporous graphene and the application of its nanocomposite membrane in propylene/propane separation." Functional Materials Letters 08, no. 02 (April 2015): 1550019. http://dx.doi.org/10.1142/s1793604715500198.

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Chemically reduced graphene oxide containing hydroxyl groups and a wide size distribution of nanopores was prepared by a facile one-pot hydrothermal method. The resulting material was characterized by transmission electron microscopy (TEM), Raman spectroscopy, surface area measurement and attenuated total reflection infrared spectroscopy (ATR-FTIR), respectively. It was found that this reduced graphene oxide exhibited more clear nanopores and hydroxyl groups in the basal plane. Then the morphologies of the nanocomposite membrane incorporated into the nanoporous graphene were investigated through scanning electron microscopy (SEM), and the permeation test also was performed. Notably, the results showed that the nanocomposite membrane had a homogenous morphology and a better performance (separation factor 11.09) than polymer membrane in the separation of propylene/propane. This work demonstrates that nanoporous graphene exhibits great potential in the field of olefin/paraffin separation.

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35

Turkevych, Ivan, and Nobuko Fukuda. "Fabrication of nanostructured Pt electrodes templated by nanoporous anodic alumina for electrochemical sensors." Japanese Journal of Applied Physics 61, SD (March 2, 2022): SD1002. http://dx.doi.org/10.35848/1347-4065/ac51be.

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Abstract Although platinum electrodes are widely used in electrochemical sensors their functionality can be affected by formed components of complex biological fluids. We demonstrated a simple approach to the formation of Pt nanopillars sandwiched between W metal layers and nanoporous anodic alumina membranes, by anodization of W/Al bilayers and substitution of WO3 nanopillars formed by the local anodization of W under the nanopores with Pt. By exploiting the Pourbaix corrosion diagram of W, we could find conditions that allow the selective dissolution of WO3 in pH = 7.4 buffer solution and formation of Pt nanopillars inside the nanoporous aluminum membrane via electroless deposition.

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36

Carvajal, Joan J., Oleksandr V. Bilousov, Dominique Drouin, Magdalena Aguiló, Francesc Díaz, and J. Carlos Rojo. "Chemical Vapor Deposition of Porous GaN Particles on Silicon." Microscopy and Microanalysis 18, no. 4 (July 26, 2012): 905–11. http://dx.doi.org/10.1017/s1431927612001134.

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AbstractWe present a technique for the direct deposition of nanoporous GaN particles on Si substrates without requiring any post-growth treatment. The internal morphology of the nanoporous GaN particles deposited on Si substrates by using a simple chemical vapor deposition approach was investigated, and straight nanopores with diameters ranging between 50 and 100 nm were observed. Cathodoluminescence characterization revealed a sharp and well-defined near band-edge emission at ∼365 nm. This approach simplifies other methods used for this purpose, such as etching and corrosion techniques that can damage the semiconductor structure and modify its properties.

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37

Liu, Xinyu, Dongxun Lyu, Céline Merlet, Matthew J. A. Leesmith, Xiao Hua, Zhen Xu, Clare P. Grey, and Alexander C. Forse. "Structural disorder determines capacitance in nanoporous carbons." Science 384, no. 6693 (April 19, 2024): 321–25. http://dx.doi.org/10.1126/science.adn6242.

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The difficulty in characterizing the complex structures of nanoporous carbon electrodes has led to a lack of clear design principles with which to improve supercapacitors. Pore size has long been considered the main lever to improve capacitance. However, our evaluation of a large series of commercial nanoporous carbons finds a lack of correlation between pore size and capacitance. Instead, nuclear magnetic resonance spectroscopy measurements and simulations reveal a strong correlation between structural disorder in the electrodes and capacitance. More disordered carbons with smaller graphene-like domains show higher capacitances owing to the more efficient storage of ions in their nanopores. Our findings suggest ways to understand and exploit disorder to achieve highly energy-dense supercapacitors.

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38

Chogani, A., A. Moosavi, and M. Rahiminejad. "Numerical Simulation of Salt Water Passing Mechanism Through Nanoporous Single-Layer Graphene Membrane." Chemical Product and Process Modeling 11, no. 1 (March 1, 2016): 73–76. http://dx.doi.org/10.1515/cppm-2015-0068.

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Abstract In recent years carbon nanotubes and other carbon nanostructures such as graphene sheets have attracted a lot of attention due to their unique mechanical, thermal and electrical properties. These structures can be used in desalination of sea water, removal of hazardous substances from water tanks, gases separation, and so on. The nanoporous single layer graphene membranes are very efficient for desalinating water due to their very low thickness. In this method, water-flow thorough the membrane and salt rejection strongly depend on the applied pressure and size of nanopores that are created in graphene membrane. In this study, the mechanism of passing water and salt ions through nanoporous single-layer graphene membrane are simulated using classical molecular dynamics. We examined the effects of applied pressure and size of nanopores on desalination performance of NPG membrane. Unlike previous researches, we considered the flexibility of the membrane. The results show that by increasing the applied pressure and diameter of the nanopores, water-flow through membrane increases, meanwhile salt rejection decreases.

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39

Zeng, Chunhong, Yameng Xu, Yongjian Ma, Tiwei Chen, Xiaodong Zhang, Qi Cui, Ting Lei, et al. "Solar-blind ultraviolet detector based on ordered nanoporous β-Ga₂O₃ film." Japanese Journal of Applied Physics 61, no. 4 (March 17, 2022): 042004. http://dx.doi.org/10.35848/1347-4065/ac541e.

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Abstract The β-Ga2O3 ultraviolet (UV) detectors work in the solar-blind (UV) band due to the ultra-wide bandgap of β-Ga2O3. In this paper, a solar-blind ultraviolet detector based on an ordered nanoporous β-Ga2O3 (ONP-β-Ga2O3) film is proposed and implemented. The local enhancement effect of the ordered nanopores on light is simulated by finite-difference time-domain method, and the period and diameter of the nanopores are optimized. Graphene is transferred on the ONP-β-Ga2O3 film and prepared as interdigital electrodes of the solar-blind ultraviolet detectors. The optimal detector has a photo-to-dark current ratio of about 4.64 × 103 at a 5 V bias, a peak response of 2.43 A W−1 at 254 nm, and a UV/visible rejection ratio of about 1081. We demonstrate that the ordered nanoporous structure can localize optical field effectively, which results in enhancement of light absorption as well as improvement of key detector parameters.

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40

Lu, Weiyi, Venkata K. Punyamurtula, Aijie Han, Taewan Kim, and Yu Qiao. "A thermally sensitive energy-absorbing composite functionalized by nanoporous carbon." Journal of Materials Research 24, no. 11 (November 2009): 3308–12. http://dx.doi.org/10.1557/jmr.2009.0408.

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A polypropylene-matrix composite material functionalized by nanoporous particulates was produced. When the temperature is relatively low, the matrix dominates the system behavior. When the temperature is relatively high, with a sufficiently large external pressure the polymer phase can be intruded into the nanopores, providing an energy absorption mechanism.

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41

Wang, Xiu Li, and Qiu Ming Gao. "Synthesis of Copper(0) Nanoparticles in Nanoporous Nickel Phosphate VSB-1." Solid State Phenomena 121-123 (March 2007): 479–82. http://dx.doi.org/10.4028/www.scientific.net/ssp.121-123.479.

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Copper(0) nanoparticles in nanoporous nickel phosphate VSB-1 were prepared by the methods of ion exchange and hydrogen reduction. X-ray powder diffraction (XRD) results show that the crystal structure of VSB-1 was well retained after the encapsulation of copper nanoparticles and no apparent evidence of crystalline copper was observed. The Cu 2p core level binding energies were consistent with elemental Cu(0) appear in the X-ray photoelectron spectroscopy (XPS) data. Room temperature ultra violet visible (UV-Vis) absorption spectrum is characteristic of Cu(0) nanoparticles [1, 2]. Nanoporous material VSB-1 is an excellent host to synthesize metal or metal oxide nanoparticles due to its homogeneous nanopores and its high thermal stability.

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42

Her, Hyun-Jung, Jung-Min Kim, C. J. Kang, and Yong-Sang Kim. "Fabrication of Thin Film Titania with Nanopores, Nanopoles, and Nanopipes by Nanoporous Alumina Template." Journal of Nanoscience and Nanotechnology 8, no. 9 (September 1, 2008): 4808–12. http://dx.doi.org/10.1166/jnn.2008.ic84.

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We demonstrate the formation of thin film titania (TiO2) with a dense array of nanopores, nanopoles, and nanopipes. The heights of pores, poles, and pipes were approximately 130 nm, 180 nm, and 200 nm, respectively. The aspect ratios of these three structures were approximated between 2 and 3. In order to obtain titania thin films, a nanoporous alumina (Al2O3) template was fabricated by performing a two-step anodization process. The spin-coated titania films were uniformly patterned by a nanoimprinting lithography technique with a textured poly(methyl methacrylate) (PMMA) mold or nanoporous alumina template. The titania films are very useful for solar cells, photocatalytic and sensing applications, in which nano-structuring of surfaces with controlled dimensions is vital.

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43

Kang, Hyeon Koo, In-Gu Lee, Kyong-Hwan Lee, Beom-Sik Kim, Tae Su Jo, Kwang-Seok Chea, Sung Hoon Park, Sang-Chul Jung, and Young-Kwon Park. "Catalytic Rapid Pyrolysis ofQuercus variabilisover Nanoporous Catalysts." Journal of Nanomaterials 2015 (2015): 1–6. http://dx.doi.org/10.1155/2015/251974.

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Catalytic rapid pyrolysis ofQuercus variabilis, a Korean native tree species, was carried out using Py-GC/MS. Mesoporous MFI, which has both nanopores and micropores, and three nanoporous materials, Al-MCM-41, Al-SBA-15, andγ-Al2O3, were used as the catalyst. The acid sites of mesoporous MFI were strong Brønsted acid sites, whereas those of nanoporous materials were mostly weak acid sites. The composition of the product bio-oil varied greatly depending on the acid characteristics of the catalyst used. Phenolics were the most abundant species in the bio-oil, followed by acids and furanics, obtained over Al-MCM-41 or Al-SBA-15 with weak acid sites, whereas aromatics were the most abundant species produced over mesoporous MFI with strong acid sites, followed by phenolics. Aromatics, phenolics, and furanics are all important chemicals contributing to the improvement of bio-oil quality.

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44

Zhao, Lei. "Egg albumen - a promising material for fabrication of nanoporous mats." Thermal Science 20, no. 3 (2016): 1014–15. http://dx.doi.org/10.2298/tsci1603014z.

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The natural protein, egg albumen, is used for fabrication of nanoporous mats by bubbfil electrospinning. In our experiment, starch is used as an additive. By suitable choices of the spinning conditions, a mat with nanopores can be produced, and the spinning process is tenable by controlling the thermodynamic properties of spun solution and spinning environment.

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45

Ohgai, Takeshi, Masayuki Mizumoto, Shigeki Nomura, and Akio Kagawa. "Electrodeposition of Metallic Nanowires in Nanoporous Polycarbonate Films." Materials Science Forum 539-543 (March 2007): 1253–57. http://dx.doi.org/10.4028/www.scientific.net/msf.539-543.1253.

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A polycarbonate membrane filter with numerous cylindrical nanopores was used as a template for growing metallic nanowires such as Ni, Co and Fe. The nanoporous template with pore-diameter of 150 nm, pore-length of 6000 nm, and pore-density of 108 pore•cm-2 was modified as a cathode with sputter-deposited gold layer. Inside the nano-pores, the metallic nanowires were electrochemically deposited from an acidic sulfate solution containing metal ions. The growth rate of metallic nanowires depended on the cathode potential during electrodeposition. The diameter of electrodeposited nanowires corresponded to that of nanopores in the template. TEM diffraction pattern suggested that each metallic nanowire composed of a single crystalline structure.

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46

Kim, Y., Soo Ryong Kim, Kun Hang Cho, Seong Youl Bae, and Woo Teck Kwon. "Preparation of SiC Nanoporous Membrane for Hydrogen Separation at High Temperature." Materials Science Forum 510-511 (March 2006): 926–29. http://dx.doi.org/10.4028/www.scientific.net/msf.510-511.926.

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Nanoporous SiC membrane was developed on the porous alumina plate for the hydrogen separation using preceramic polymers such as polyphenylcarbosilane. The prepared preceramic polymers were characterized with FT-IR, TGA, GPC and XRD. Nanoporous SiC membrane was derived from the preceramic polymer using a spin coating method. The SiC membrane spin coated using 20 wt.% of polyphenylcarbosilane solution in cyclohexane does not show any cracks on the surface after heat treatment at 800oC. The average thickness of the SiC membrane is about 1µm. SiC coated porous alumina possesses asymmetric pore size distribution. There are micropores that originated from porous alumina substrate, and nanopores that derived from amorphous state of SiC membranes. The pore size distribution measurement showed that the sample contains 1-3 nm sized nano pores.

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47

Luchenko, A. I. "Photoelectrical properties of nanoporous silicon." Semiconductor Physics Quantum Electronics and Optoelectronics 15, no. 3 (September 25, 2012): 298–301. http://dx.doi.org/10.15407/spqeo15.03.298.

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48

Wang, Jiangtao, Chi Cheng, and Jing Kong. "Cascaded Compression of the Size Distribution of Nanopores in Monolayer Graphene." ECS Meeting Abstracts MA2023-01, no. 13 (August 28, 2023): 1293. http://dx.doi.org/10.1149/ma2023-01131293mtgabs.

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Nanoporous graphene has shown great promise for membrane separations. Its atomic thickness, remarkable mechanical, chemical, and thermal robustness could enable ultrahigh-flux membrane processes addressing persistent challenges in a wide range of separation needs. On the other hand, molecular separations across nanoporous graphene rely dominantly on size-based mechanisms (e.g, size exclusion) that is highly sensitive to the nanopore size and size distribution of nanopore ensemble created on the graphene. However, among existing nanopore creation methods, the process of nanopore nucleation is often coupled with nanopore expansion, which results in a lognormal nanopore size distribution with a long tail. It remains a challenge to obtain both high density and narrow size distribution of nanopores in graphene. Here, we report a cascaded compression approach to engineering nanopores in monolayer graphene for molecular separations with the assistance of electrical control of chemical vapor deposition of graphene[1]. The formation of nanopores is split into many small steps, in each of which the size distribution of all the existing nanopores is compressed by a combination of shrinkage and expansion, and at the same time of expansion, a new batch of nanopores is created, leading to increased nanopore density by each cycle. As a result, high-density nanopores with a short-tail size distribution are obtained by the cascaded compression that show high rejection and ultrafast organic solvent nanofiltration exceeding the state-of-the-art. Reference [1] Wang J, Park J H, Lu A Y, et al. Electrical Control of Chemical Vapor Deposition of Graphene. Journal of the American Chemical Society, 20

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49

Srisuwan, Y., N. Kotsaeng, Y. Baimark, N. Narkkong, and W. Simchuer. "Study on Morphology and Thermal Stability of Nanoporous Silk Fibroin Films." Advanced Materials Research 55-57 (August 2008): 721–24. http://dx.doi.org/10.4028/www.scientific.net/amr.55-57.721.

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Nanoporous silk fibroin (SF) films were prepared as SF film loaded with methoxy poly(ethylene glycol)-b-poly(D,L-lactide) (MPEG-b-PDLL) nanoparticles by film casting of MPEG-b-PDLL nanoparticle suspension-SF solution. Nanoporous structures of the SF films were formed due to self-condensation and nanophase separation of nanoparticles from SF film matrix during drying process. The films with SF/MPEG-b-PDLL ratios of 20/1, 20/2 and 20/3 (w/w) were prepared and investigated. The MPEG-b-PDLL nanoparticles can be observed on film surface and cross-section with 100-300 nm in size. The size of interconnected nanopore was in the range of 20 – 300 nm. The number and size of nanopores increased as increasing the MPEG-b-PDLL ratio. Thermal stability of the films studied from differential thermogravimetric (DTG) thermogram found that the nanoparticles dispersed into the SF films could improve thermal stability of each component. This indicated strong hydrogen bond interactions between SF and MPEG-b-PDLL were existed. Film transparency of the SF nanoporous films decreased when the MPEG-b-PDLL ratio was increased.

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50

Baban, Navajit S., Ajymurat Orozaliev, Sebastian Kirchhof, Christopher J. Stubbs, and Yong-Ak Song. "Biomimetic fracture model of lizard tail autotomy." Science 375, no. 6582 (February 18, 2022): 770–74. http://dx.doi.org/10.1126/science.abh1614.

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Lizard tail autotomy is an antipredator strategy consisting of sturdy attachment at regular times but quick detachment during need. We propose a biomimetic fracture model of lizard tail autotomy using multiscale hierarchical structures. The structures consist of uniformly distributed micropillars with nanoporous tops, which recapitulate the high-density mushroom-shaped microstructures found on the lizard tail’s muscle fracture plane. The biomimetic experiments showed adhesion enhancement when combining nanoporous interfacial surfaces with flexible micropillars in tensile and peel modes. The fracture modeling identified micro- and nanostructure-based toughening mechanisms as the critical factor. Under wet conditions, capillarity-assisted energy dissipation pertaining to liquid-filled microgaps and nanopores further increased the adhesion performance. This research presents insights on lizard tail autotomy and provides new biomimetic ideas to solve adhesion problems.

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Journal articles on the topic 'Nanoporous'

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