Готові списки джерел за темами / Zinc Oxide Nanocrystal

Добірка наукової літератури з теми "Zinc Oxide Nanocrystal"

Автор: Grafiati

Опубліковано: 14 березня 2023

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Статті в журналах з теми "Zinc Oxide Nanocrystal"

Lysytsya, A. V., M. V. Moroz, B. D. Nechyporuk, B. P. Rudyk, and B. F. Shamsutdinov. "Physical Properties of Zinc Compounds Obtained by Electrolytic Method." Physics and Chemistry of Solid State 22, no. 1 (March 18, 2021): 160–67. http://dx.doi.org/10.15330/pcss.22.1.160-167.

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The influence of the chemical composition of the electrolyte and its temperature on the process of sythesis of nanosized zinc compounds by electrolytic method using zinc electrodes was investigated. X-ray studies have been conducted and its results were used to determine the composition of the obtained nanocrystal samples and its dimensioning using the Debye and the Williamson Hall methods. Comparisons of the results of dimensioning of nanocrystals by both methods were made. Also discussed the possibilities of synthesis of nanoparticles of zinc oxide, zinc sulfide and hydrozincite by electrolytic method. It is shown, that depending on the electrolyte composition, nanocrystals of zinc oxide, zinc sulfide, hydrozincite or their mixture are obtained. The effect of thermal annealing on the samples composition and dimensioning was investigated.

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Chai, Zhimin, Xinchun Lu, and Dannong He. "Friction mechanism of zinc oxide films prepared by atomic layer deposition." RSC Advances 5, no. 68 (2015): 55411–18. http://dx.doi.org/10.1039/c5ra05355b.

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Long, Mei, Huan Yuan, Ping Sun, Lei Su, and Xiangping Jiang. "UV-Assisted Room Temperature Gas Sensing with ZnO-Ag Heterostructure Nanocrystals Studied by Photoluminescence." Journal of Nanoscience and Nanotechnology 21, no. 9 (September 1, 2021): 4865–69. http://dx.doi.org/10.1166/jnn.2021.19121.

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Noble metal-metal oxide nanohybrids play a significant contribution in gas sensing applications at room temperature. Here, Ag-loaded ZnO with different Ag doping concentration are prepared by two-step polymer-network gel method, and NO2 sensing characteristics are tested at room temperature with various concentrations. The nanocrystal sizes are found to be more uniform with increasing with Ag concentration, and photoluminescence spectroscopy further reveals the different defects in ZnO–Ag nanocrystal lattices: pure ZnO has the largest intensity of the conduction band to valence band combination, and ZnO–Ag-1 (1 mol% Ag doping concentration) has the largest oxygen vacancy content, while ZnO–Ag-3 (3 mol% Ag doping concentration) has the largest excess zinc interstitial. It is showed that the gas sensing properties are independent of the size of nanocrystals, and more dependent on the nanocrystal defect structure. In this work, a new sensing mechanism is proposed according to the experimental results.

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Spoerke, Erik D., Matthew T. Lloyd, Yun-ju Lee, Timothy N. Lambert, Bonnie B. McKenzie, Ying-Bing Jiang, Dana C. Olson, Thomas L. Sounart, Julia W. P. Hsu, and James A. Voigt. "Nanocrystal Layer Deposition: Surface-Mediated Templating of Cadmium Sulfide Nanocrystals on Zinc Oxide Architectures." Journal of Physical Chemistry C 113, no. 37 (August 21, 2009): 16329–36. http://dx.doi.org/10.1021/jp900564r.

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Neshchimenko, Vitaly, Chundong Li, Mikhail Mikhailov, and Jinpeng Lv. "Optical radiation stability of ZnO hollow particles." Nanoscale 10, no. 47 (2018): 22335–47. http://dx.doi.org/10.1039/c8nr04455d.

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The research is focused on the effect of irradiation by protons and electrons on the optical properties’ stability of zinc oxide hollow particles as compared with ball, star and flower shaped particles, as well as micro- and nanocrystal powders.

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Satienpattanakoon, C., D. Yiamsawas, Wiyong Kangwansupamonkon, and R. Nuisin. "Synthesis and Characterization of Zinc Oxide Nanocrystals by Solid-State and Solvothermal Techniques." Advanced Materials Research 55-57 (August 2008): 657–60. http://dx.doi.org/10.4028/www.scientific.net/amr.55-57.657.

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The nanostructural zinc oxide (ZnO) particles have been synthesized by two techniques, solid-state reaction and solvothermal method. The solid-state reaction method, the ZnO nanoparticles were carried out by reacting zinc acetate with sodium hydroxide in sodium dodecyl sulfate (SDS) and beta-cyclodextrin (b-CD). The effects of reaction condition on the nanocrystal morphology were investigated. The physical properties of ZnO were characterized using X-ray diffraction technique and transmission electron microscopy. The results showed that the obtained ZnO nanorods were in the wurtzite structure with various sizes of single crystals. FT-IR analysis also confirmed the binding of SDS with ZnO nanorods. For the solvothermal technique, ZnO nanostructures with various morphologies were synthesized from the treatment of zinc acetate at 80°C with the selected polymeric surfactant, poly(vinyl pyrrolidone) (PVP), in aqueous solution and ethylene glycol. The results showed that the selected surfactant and solvent play a different role in controlling the morphologies of the ZnO nanocrystals. The ZnO nanorods and nanoparticles were successfully obtained. The XRD result revealed that the ZnO is in the wurtzite structure with the particle size in range of 270-1300 nm. The optical properties of the samples were also studied via UV-vis spectrophotometer.

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Wang, Yazi, Hongfei Hua, Wei Li, Ruili Wang, Xiaoze Jiang, and Meifang Zhu. "Strong antibacterial dental resin composites containing cellulose nanocrystal/zinc oxide nanohybrids." Journal of Dentistry 80 (January 2019): 23–29. http://dx.doi.org/10.1016/j.jdent.2018.11.002.

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Lee, S. C., Q. Hu, J. Y. Lee, Y. J. Baek, H. H. Lee, and T. S. Yoon. "Nanocrystal Floating Gate Memory with Indium-Gallium-Zinc-Oxide Channel and Pt-Fe2O3 Core-Shell Nanocrystals." ECS Transactions 50, no. 8 (March 15, 2013): 281–87. http://dx.doi.org/10.1149/05008.0281ecst.

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Hu, Quanli, Sang-Hyub Ha, Hyun Ho Lee, and Tae-Sik Yoon. "Nanocrystal floating gate memory with solution-processed indium-zinc-tin-oxide channel and colloidal silver nanocrystals." Semiconductor Science and Technology 26, no. 12 (November 16, 2011): 125021. http://dx.doi.org/10.1088/0268-1242/26/12/125021.

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Hue, Ryan J., Rajan Vatassery, Kent R. Mann, and Wayne L. Gladfelter. "Zinc oxide nanocrystal quenching of emission from electron-rich ruthenium-bipyridine complexes." Dalton Transactions 44, no. 10 (2015): 4630–39. http://dx.doi.org/10.1039/c4dt03272a.

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Heteroleptic tris(bipyridine)ruthenium complexes bearing one dicarboxybipyridine ligand bind to dispersed ZnO nanocrystals. Electron releasing amino substituents on the remaining bipyridines raise the excited state potential high enough to allow excited state electron transfer into the ZnO.

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Дисертації з теми "Zinc Oxide Nanocrystal"

Newton, Marcus Christian. "Zinc oxide tetrapod nanocrystal diodes." Thesis, University College London (University of London), 2007. http://discovery.ucl.ac.uk/1446460/.

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Advances in fabrication and analysis tools have allowed the synthesis and manipulation of functional materials with features comparable to fundamental physical length scales. Many interesting properties inherently due to quantum size effects have been observed in nanometre scale structures. It is hoped that these nanoscale structures will play a key role in future materials and devices that exploit their unique properties. Zinc oxide (ZnO) is a wide band-gap transparent and piezoelectric semiconductor material. It also has a large exciton binding energy which allows for stable ultraviolet light emission at room temperature. There are therefore foreseeable applications in optoelectronic devices which include ultraviolet photosensitive devices and light emitting diodes. Nanoscale structures formed from ZnO are interesting as they possess many of the properties inherent form the bulk but are also subject to various quantum size effects that may occur at the nanoscale. To date, the study of ZnO nanostructures is a relatively recent endeavour with the vast majority of reports being made within the last five years. ZnO is unique in that it forms a family of nanoscale structures. These structures include nanoscale wires, rods, hexagons, tetrapods, ribbons, rings, flowers and helixes. This work is focussed on the study of zinc oxide tetrapod crystalline nanoscale structures and their devices. We have synthesised ZnO tetrapods using chemical vapour transport techniques. Photoluminescence characterisation revealed the presence of optically active surface defects that could be quenched with a simple surface treatment. We have also for the first time observed resonant cavity modes in a single ZnO tetrapod nanocrystal. An ultraviolet sensitive Schottky diode was fabricated from a single ZnO tetrapod using focussed ion-beam assisted deposition techniques. The device characteristics observed were modelled and successfully shown to result from an illumination induced reduction in the Schottky barrier height at the metal-semiconductor interface.

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Muley, Amol. "Synthesis and characterization of nanostructured metallic zinc and zinc oxide." Thesis, Click to view the E-thesis via HKUTO, 2007. http://sunzi.lib.hku.hk/hkuto/record/B39101538.

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Spina, Carla. "Zinc oxide semiconducting nanocrystals : scaffolds for intrinsic and extrinsic defects." Thesis, McGill University, 2009. http://digitool.Library.McGill.CA:80/R/?func=dbin-jump-full&object_id=115869.

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As a material whose applications are many and growing, zinc oxide still remains a complex system whose photoluminescent (PL), structural, electrical, and photocatalytic properties have not been fundamentally understood. The luminescent properties of zinc oxide (ZnO) nanocrystals (NCs) are very sensitive to crystal structure, and defect states in zinc oxide, which in turn is very sensitive to preparation methods, post-synthesis workup, and thermal treatments. Understanding and managing this rich defect chemistry is critical to controlling ZnO properties. As the surface-to-volume ratio of ZnO increases as materials enter the quantum regime, the surface defects play a stronger role. The exact role of the defect states and their contribution to the physical and chemical properties of ZnO has been studies in great lengths yet still remains controversial.

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Lander, Sanna. "Rapid microwave assisted growth of ZnO nanocrystals: effects of heating power and zinc precursor." Thesis, Karlstads universitet, Institutionen för ingenjörsvetenskap och fysik, 2014. http://urn.kb.se/resolve?urn=urn:nbn:se:kau:diva-33269.

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The subject of this thesis is microwave assisted rapid growth of ZnO nanoparticles from an aqueous solution using different zinc precursors and heating powers, and characterization of these by scanning electron microscopy, atomic force microscopy and optical microscopy. The goal of the experiment performed was to study the effect of the heating power of the microwave oven as well as that of the zinc precursor used on the morphology and size of the grown particles. ZnO nanoparticles has many interesting possible applications in a wide range of areas, such as LED-technology, medicine, antibacterial applications, solar cells and more. Also, there is still a lot of knowledge missing concerning the growth mechanisms and properties of ZnO on the nano-scale. These two facts give good reasons to continue the research and investigations of nano-ZnO. Being able to use the microwave assisted growth method in large scale is highly interesting as it is relatively cheap, safe and easy compared to other presently used methods, so there are good reasons to learn more about this technique as well. In this project it was found that both the heating power and the zinc precursor used had significant effects on the morphology and size of the grown ZnO nanocrystals, and also that adding a zinc seed layer to the surface of the substrate before growth made a big difference in some cases.

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Tu, Wei-Lun Scharf Thomas W. "Processing, structure, and tribological property interrelationships in sputtered nanocrystalline ZnO coatings." [Denton, Tex.] : University of North Texas, 2009. http://digital.library.unt.edu/ark:/67531/metadc12207.

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Zakhtser, Alter. "Synthesis and Reactivity of PtZn Nanostructures and Nanocrystals for Heterogeneous Catalysis Applications." Thesis, Sorbonne université, 2019. https://accesdistant.sorbonne-universite.fr/login?url=http://theses-intra.upmc.fr/modules/resources/download/theses/2019SORUS434.pdf.

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Le but de cette thèse était d'explorer la chimie de surface des systèmes bimétalliques platine-zinc et leur activité catalytique dans la réaction d'oxydation du CO. La recherche sur ce système bimétallique a été menée sur deux fronts: une étude de surface du système modèle , une couche unique de ZnO discontinue épitaxiée sur du Pt (111), utilisant la microscopie à effet tunnel et le rayonnement synchrotron à proximité de la photoémission par rayons X à pression ambiante, et une étude davantage axée sur la «nanomatériau» du même système bimétallique, en utilisant la chimie complexe de la synthèse colloïdale , microscopie électronique à transmission et à balayage, et enfin XPS de laboratoire.Tout d'abord, une surface modèle constituée d'un film monocouche de ZnO supporté sur du Pt (111) a été fabriquée dans des conditions de vide très poussé. Sa chimie de surface a été explorée par STM puis par rayonnement synchrotron NAP-XPS dans des conditions opératoires. Nous avons pu prouver que ce système était bien un cas typique de catalyse inverse. Les effets synergiques dus à la présence des deux matériaux ont été bien observés, mais uniquement à basse température (jusqu'à 410 K). Au-delà de cette température, les effets de transport de masse empêchent la comparaison de la réactivité des surfaces de ZnO / Pt (111) et de Pt (111). Nous avons montré que des intermédiaires de réaction doivent être formés dans la zone frontière entre le ZnO et le platine, lorsque le film de ZnO est discontinu. Nous avons mis en évidence le rôle clé joué par les hydroxyles présents dans les plaques de ZnO, qui sont dus à la dissociation de H2 ou de H2O de l’atmosphère résiduelle des plaques de platine. En particulier, nous avons détecté par NAP-XPS la présence d'une espèce carboxyle (due à l'association de OH avec CO), qui précède la désorption du CO2. Au-dessus de 410 K, un formiate apparaît et cette dernière espèce est probablement spectatrice du processus d'oxydation du CO. Le transfert des connaissances accumulées dans les précédentes études de la science des surfaces et des catalyseurs modèles au cas plus réaliste des nanocristaux de l’alliage PtZn, tout en aidant à identifier certains phénomènes courants, il montre également ses limites. En fait, les nanocristaux revêtus de leurs ligands oléylamine ont des caractéristiques que les surfaces des modèles UHV ne possèdent pas, en raison du processus de fabrication de la CN lui-même: nous avons trouvé des indices spectroscopiques de la présence d’eau (éventuellement un sous-produit de la réaction, résultant d’une entre la cétone et l'amine); de plus, un recouvrement de la surface du platine par des atomes d'hydrogène est actuellement une explication de nombreux phénomènes observés. Trouver les conditions expérimentales pour produire des nano-alliages bimétalliques à partir de deux précurseurs métal-acac2 était une tâche ardue, bien plus que celle de déposer physiquement un film mince sur un monocristal d’UHV. Nos efforts ont été récompensés car nous avons pu produire des CN en alliage PtZn. C'est l'un des principaux points de la présente étude. La présence de Pt(acac)2 empêche le zinc (dont l'oxydation complète en ZnO, comme c'est le cas lorsque le Zn(acac)2 seul est présent dans l'oléylamine. L'XPS monochromatisé montre que le zinc fabrique un alliage avec le platine, où il reste métallique alors qu’une autre fraction est sous la forme de ZnO, il n’est pas clair si deux canaux de réaction sont en concurrence (alliage PtZn versus oxydation de Zn par l’eau), ou Zn est oxydé par la suite, c’est-à-dire après exposition à l’air. Les CN alliés ont été étudiés en détail par des méthodes avancées de microscopie électronique (y compris dans des conditions opératoires), de diffraction et d’EDS [...]
The purpose of this thesis was to explore the surface chemistry of platinum-zinc bimetallic systems, and their catalytic activity in the oxidation reaction of CO. The research on this bimetallic system was carried out on two fronts: a surface science study of the model system, a discontinuous ZnO single layer epitaxied on Pt(111), using scanning tunneling microscopy and synchrotron radiation near ambien pressure x-ray photoemission, and a more “nanomaterial science” oriented study of the same bi-metallic system, using complex colloidal synthesis chemistry, transmission and scanning electron microscopy, and finally laboratory XPS. First, a model surface consisting of a ZnO monolayer film supported on Pt(111) was fabricated under ultra-high vacuum conditions. Its surface chemistry was explored by STM and then by synchrotron radiation NAP-XPS under operando conditions. We were able to prove that this system was indeed a typical case of inverse catalysis. Synergetic effects due to the presence of both materials were well seen, but only at low temperatures (up to 410 K). Beyond that temperature, mass transport effects prevent the reactivity of the ZnO/Pt(111) and Pt(111) surfaces from being compared. We have shown that reaction intermediates must be formed in the border area between ZnO and platinum, when the ZnO film is discontinuous. We have highlighted the key role played by the hydroxyls present only ion the ZnO patches, which are due to the dissociation of H2 or H2O from the residual atmosphere on the platinum patches. In particular, we have detected by NAP-XPS the presence of a carboxyl species (due to the association of OH with CO), which precedes the desorption of CO2. Above 410 K, a formate appears, and the latter species is likely a spectator in the CO oxidation process. The transfer of the knowledge accumulated in the preceding surface science and model catalysts studies, to the more realistic case of nanocrystals of the PtZn alloy, while it helped identify some common phenomena, it also shows its limitations. In fact the NC coated with their oleylamine ligands have characteristics that UHV model surfaces do not possess, due to the NC fabrication process itself: we have found spectroscopic hints of the presence of water (possibly a byproduct of the reaction, arising from a condensation reaction between the ketone and the amine); in addition, a capping of the platinum surface by H atoms, is, at present, explanatory of many observed phenomena. Finding the experimental conditions to produce bimetallic nano-alloys from two metal-acac2 precursors was a daunting task, much more than that of physically depositing a thin film on a UHV monocrystal. Our efforts were rewarded as we were able to produce PtZn alloy NCs. This one of the main points of the present study. The presence of Pt(acac)2 prevents zinc (whose from being fully oxidized to ZnO, which is the case when Zn(acac)2 alone is present in oleylamine. Monochromatized XPS shows that zinc makes an alloy with platinum, where it remains metallic, while another fraction is under the form of ZnO. It is not completely clear whether two reaction channels are in competion (PtZn alloying versus Zn oxidation by water), or Zn is oxidized afterwards, i.e. after exposure to air. The alloyed NCs have been studied in detail by advanced methods of electron microscopy (including under operando conditions), diffraction and EDS. Unlike the case of the surface model where the STM images were particularly telling, we do not have at this stage of the study an exact model of the interface between the metal alloy and the zinc oxide that surrounds it. On the other hand, we know that the core of the NCs is occupied by the PtZn alloy, and that the outer planes are identical to those of pure platinum. [...]

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Chang, Jin. "Controlled synthesis of inorganic semiconductor nanocrystals and their applications." Thesis, Queensland University of Technology, 2013. https://eprints.qut.edu.au/63960/1/Jin_Chang_Thesis.pdf.

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This thesis is a comprehensive study of the synthesis of nanomaterials. It explores the synthetic methods on the control of the size, shape and phase of semiconductor nanocrystals. A number of important conclusions, including the mechanism behind crystal growth and the structure-relationship, have been drawn through the experimental and theoretical investigation. The synthesized nanocrystals have been tested for applications in gas sensing, photocatalysis and solar cells, which exhibit considerable commercialization potential.

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Urgessa, Zelalem Nigussa. "Growth and characterization of ZnO nanorods using chemical bath deposition." Thesis, Nelson Mandela Metropolitan University, 2012. http://hdl.handle.net/10948/d1021124.

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Semiconductor devices are commonplace in every household. One application of semiconductors in particular, namely solid state lighting technology, is destined for a bright future. To this end, ZnO nanostructures have gained substantial interest in the research community, in part because of its requisite large direct band gap. Furthermore, the stability of the exciton (binding energy 60 meV) in this material, can lead to lasing action based on exciton recombination and possibly exciton interaction, even above room temperature. Therefore, it is very important to realize controllable growth of ZnO nanostructures and investigate their properties. The main motivation for this thesis is not only to successfully realize the controllable growth of ZnO nanorods, but also to investigate the structure, optical and electrical properties in detail by means of scanning electron microscopy (SEM), transmission electron microscopy (TEM), photoluminescence (PL) spectroscopy (steady state and time resolved) and X-ray diffraction (XRD). Furthermore, strong rectification in the ZnO/p-Si heterojunction is demonstrated. Nanorods have been successfully synthesized on silicon by a two-step process, involving the pre-coating of the substrate by a seed layer, followed by the chemical bath deposition of the nanorods. ZnO seed layers with particle sizes of about 5 nm are achieved by the thermal decomposition of zinc acetate dihydrate dissolved in ethanol. The effects of the seed layer density on the distribution, alignment and uniformity of subsequently grown nanorods were studied. The aspect ratio, orientation and distribution of nanorods are shown to be well controlled through adjusting the density of the ZnO nanoparticles pre-coated onto the substrates. It is shown that the seed layer is a prerequisite for the growth of well aligned ZnO nanorods on lattice mismatched Si substrate. The influence of various nanorod growth parameters on the morphology, optical and electrical properties of the nanorods were also systematically studied. These include the oxygen to zinc molar ratio, the pH of the growth solution, the concentration of the reactants, the growth temperature and growth time, different hydroxide precursors and the addition of surface passivating agents to the growth solution. By controlling these xii parameters different architectures of nanostructures, like spherical particles, well aligned nanorods, nanoflowers and thin films of different thicknesses are demonstrated. A possible growth mechanism for ZnO nanostructures in solution is proposed. XRD indicated that all the as-grown nanostructures produced above 45 C crystallize in the wurtzite structure and post growth annealing does not significantly enhance the crystalline quality of the material. In material grown at lower temperature, traces of zinc hydroxide were observed. The optical quality of the nanostructures was investigated using both steady-state PL and time-resolved (TR) PL from 4 K to room temperature. In the case of as-grown samples, both UV and defect related emissions have been observed for all nanostructures. The effect of post-growth annealing on the optical quality of the nanostructures was carefully examined. The effect of annealing in different atmospheres was also investigated. Regardless of the annealing environment annealing at a temperature as low as 300 C enhances the UV emission and suppresses defect related deep level emission. However, annealing above 500 C is required to out-diffuse hydrogen, the presence of which is deduced from the I4 line in the low temperature PL spectra of ZnO. TRPL was utilized to investigate lifetime decay profiles of nanorods upon different post growth treatments. The bound exciton lifetime strongly depends on the post-growth annealing temperature: the PL decay time is much faster for as grown rods, confirming the domination of surface assisted recombination. In general, the PL analysis showed that the PL of nanorods have the same characteristics as that of bulk ZnO, except for the stronger contribution from surface related bound excitons in the former case. Surface adsorbed impurities causing depletion and band bending in the near surface region is implied from both time resolved and steady state PL. Finally, although strong rectification in the ZnO/p-Si heterojunction is illustrated, no electroluminescence has been achieved. This is explained in terms of the band offset between ZnO and Si and interfacial states. Different schemes are proposed to improve the performance of ZnO/Si heterojunction light emitting devices.

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Vahidi, Ghazal. "Application of Cellulose Nanocrystals and Zinc Oxide as a Green Fire-Retardant System in High Density Polyethylene." Thesis, North Dakota State University, 2019. https://hdl.handle.net/10365/31725.

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Polymeric materials are widely used in diverse applications. However, a major weakness in the majority of the thermoplastic polymers is their lack of ability to resist fire. Most of the chemicals and additives currently used to improve fire retardancy have deleterious effects on the environment. This research focuses on developing an environmentally safe and effective fire-retardant system for high density polyethylene (HDPE), using cellulose nanocrystals (CNCs) and zinc oxide (ZnO). The effect of CNCs coated with nano ZnO has been investigated for improving the fire resistance properties of the HDPE. Improved dispersion of CNCs into HDPE matrix was achieved by employing maleic anhydride as a coupling agent. It was found that addition of CNCs-ZnO can introduce a reasonable level of flame retardancy in HDPE matrix in addition to improving the maximum tensile strength and elongation at break.

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Seregin, Vladimir Victor. "Part I, Fabrication and surface modification of composite biomaterials based on silicon and calcium disilicide Part II, Synthesis and characterization of erbium doped silicon nanocrystals encapsulated by aluminum and zinc oxides /." Fort Worth, Tex. : Texas Christian University, 2006. http://etd.tcu.edu/etdfiles/available/etd-04252006-145309/unrestricted/seregin.pdf.

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Частини книг з теми "Zinc Oxide Nanocrystal"

Suryanarayanan, R. "Zinc Oxide: From Optoelectronics to Biomaterial—A Short Review." In ZnO Nanocrystals and Allied Materials, 289–307. New Delhi: Springer India, 2013. http://dx.doi.org/10.1007/978-81-322-1160-0_14.

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Senthil Kumar, E., Shubra Singh, and M. S. Ramachandra Rao. "Zinc Oxide: The Versatile Material with an Assortment of Physical Properties." In ZnO Nanocrystals and Allied Materials, 1–38. New Delhi: Springer India, 2013. http://dx.doi.org/10.1007/978-81-322-1160-0_1.

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Kitture, Rohini, Sandip Dhobale, and S. N. Kale. "Zinc Oxide Nanomaterials as Amylase Inhibitors and for Water Pollution Control." In ZnO Nanocrystals and Allied Materials, 269–87. New Delhi: Springer India, 2013. http://dx.doi.org/10.1007/978-81-322-1160-0_13.

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de Farias Soares, Alvaro, Sonia Hatsue Tatumi, and Lilia Coronato Courrol. "TL, OSL, and PL Properties of Zinc Oxide Nanocrystals." In Luminescent Nanomaterials, 97–127. New York: Jenny Stanford Publishing, 2022. http://dx.doi.org/10.1201/9781003277385-2.

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Shimoi, Norihiro. "Nonthermal Crystalline Forming of Ceramic Nanoparticles by Non-Equilibrium Excitation Reaction Field of Electron." In Nanocrystals [Working Title]. IntechOpen, 2021. http://dx.doi.org/10.5772/intechopen.97037.

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In this work, we have discovered a method of forming ZnO thin films with high mobility, high carrier density and low resistivity on plastic (PET) films using non-equilibrium reaction fields, even when the films are deposited without heating, and we have also found a thin film formation technique using a wet process that is different from conventional deposition techniques. The field emission electron-beam irradiation treatment energetically activates the surface of ZnO particles and decomposes each ZnO particles. The energy transfer between zinc ions and ZnO surface and the oxygen present in the atmosphere around the ZnO particles induce the oxidation of zinc. In addition, the ZnO thin films obtained in this study successfully possess high functional thin films with high electrical properties, including high hole mobility of 208.6 cm2/Vs, despite being on PET film substrates. These results contribute to the discovery of a mechanism to create highly functional oxide thin films using a simple two-dimensional process without any heat treatment on the substrate or during film deposition. In addition, we have elucidated the interfacial phenomena and crosslinking mechanisms that occur during the bonding of metal oxide particles, and understood the interfacial physical properties and their effects on the electronic structure. and surface/interface control, and control of higher-order functional properties in metal/ceramics/semiconductor composites, and contribute to the provision of next-generation nanodevice components in a broad sense.

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C.A. Silva, Anielle, Eliete A. Alvin, Francisco R.A. dos Santos, Samanta L.M. de Matos, Jerusa M. de Oliveira, Alessandra S. Silva, Éder V. Guimarães, et al. "Doped Semiconductor Nanocrystals: Development and Applications." In Nanocrystals [Working Title]. IntechOpen, 2021. http://dx.doi.org/10.5772/intechopen.96753.

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This chapter aims to show significant progress that our group has been developing and the applications of several doped semiconductor nanocrystals (NCs), as nanopowders or embedded in glass systems. Depending on the type of dopant incorporated in the nanocrystals, the physical, chemical, and biological properties can be intensified. However, it can also generate undesired toxic effects that can potentially compromise its use. Here we present the potential of zinc oxide NCs doped with silver (Ag), gold (Au), and magnesium (Mg) ions to control bacterial diseases in agriculture. We have also performed biocompatibility analysis of the pure and Ag-doped sodium titanate (Na2Ti3O7) NCs in Drosophila. The doped nanocrystals embedded in glassy systems are chrome (Cr) or copper (Cu) in ZnTe and Bi2Te3 NCs for spintronic development nanodevices. Therefore, we will show several advantages that doped nanocrystals may present in the technological and biotechnological areas.

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Golia, Santosh Singh, and Manju Arora. "Zinc oxide-decorated graphene oxide nanocomposites for industrial volatile organic compound chemical sensor applications." In Industrial Applications of Nanocrystals, 219–49. Elsevier, 2022. http://dx.doi.org/10.1016/b978-0-12-824024-3.00025-7.

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Ahmed Rather, Gulzar, Saqib Hassan, Surajit Pal, Mohd Hashim Khan, Heshu Sulaiman Rahman, and Johra Khan. "Antimicrobial Efficacy of Biogenic Silver and Zinc Nanocrystals/Nanoparticles to Combat the Drug Resistance in Human Pathogens." In Nanocrystals [Working Title]. IntechOpen, 2021. http://dx.doi.org/10.5772/intechopen.99200.

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The emergence of biogenic nanomaterials as novel antimicrobials introduces a new paradigm in human health care. Based on the recent reports of the World Health Organization, infectious diseases pose one of the greatest health challenges. Increased multi-drug resistance prevalence among human pathogens, due to the inefficiency of commercially available antimicrobial drugs in the market is a great threat to humans. The poor solubility, stability and side effects of the antibacterial therapy prompted the researchers to explore new innovative strategies for developing new antimicrobials. Recently, biogenic nanoparticles have proven their effectiveness against multidrug-resistant (MDR) pathogens as an alternative to conventional antibiotics. Biogenic nanoparticles such as silver nanoparticles (AgNPs) and Zinc Oxide nanoparticles (ZnONPs) are easy to produce, biocompatible, provide enhanced uptake and are eco-friendly. Moreover, the capping of the biogenic nanocrystals provides an active surface for interaction with biological components, facilitated by free active surface functional groups to enhance their efficacy and delivery. Inorganic nanocrystals (AgNPs and ZnONPs) are effective both as nano-bactericides and as nanocarriers against sensitive and MDR) pathogens. The present chapter focuses on the utilization of the recent nanosystems to combat drug resistance in human pathogens. Nanomedicine represents a new generation of potiential antimicrobial candidates capable of combating the drug resistance in various pathogenic organisms.

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Verma, Ravi, Shanky Jha, D. Harimurugan, Srinivasan Kasthurirengan, N. C. Shivaprakash, and Upendra Behera. "Nanomaterials’ Synthesis Approaches for Energy Storage and Electronics Applications." In Current and Future Developments in Nanomaterials and Carbon Nanotubes, 240–57. BENTHAM SCIENCE PUBLISHERS, 2022. http://dx.doi.org/10.2174/9789815050714122030017.

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Nanomaterials are materials with cross-sectional dimensions varying from one to hundreds of nanometers and lengths ranging from hundreds of nanometers to millimeters. Nanomaterials either occur naturally or can be produced purposefully by performing a specialized function. Until recently, most nanomaterials have been made from carbon (carbon nanotubes), transition metals, and metal oxides such as titanium dioxide and zinc oxide. In a few cases, nanoparticles may exist in the form of nanocrystals comprising a number of compounds, including but not limited to silicon and metals. The discovery of nanomaterials has played a vital role in the emerging field of research and technology. Recently, a large amount of research efforts has been dedicated to developing nanomaterials and their applications, ranging from space to electronics applications. In this chapter, we describe the role of nanoparticles in electronics and energy storage applications, with examples including chips, displays, enhanced batteries, and thermoelectric, gas sensing, lead-free soldering, humidity sensing, and super capacitor devices. The chapter also attempts to provide an exhaustive description of the developed advanced nanomaterials and different conventional and advanced techniques adopted by researchers to synthesize the nanoparticles via bottom-up techniques (pyrolysis, chemical vapor deposition, sol-gel, and biosynthesis) and top-bottom approaches (mechanical milling, nanolithography, laser ablation, and thermal decomposition).

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Jan, Kalsoom. "Hybrid nanocomposites based on cellulose nanocrystals/nanofibrils and zinc oxides: Energy applications." In Cellulose Nanocrystal/Nanoparticles Hybrid Nanocomposites, 165–80. Elsevier, 2021. http://dx.doi.org/10.1016/b978-0-12-822906-4.00005-0.

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Тези доповідей конференцій з теми "Zinc Oxide Nanocrystal"

Tanuševski, A., M. Ristova, M. Ristov, and V. Georgieva. "Nanocrystal indium doped zinc oxide prepared by spray pyrolysis method." In SIXTH INTERNATIONAL CONFERENCE OF THE BALKAN PHYSICAL UNION. AIP, 2007. http://dx.doi.org/10.1063/1.2733542.

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Byrczek, Michal, Miroslaw Malewicz, and Helena Teterycz. "The growth of zinc oxide nanocrystals on the zinc oxide thin film by chemical bath deposition." In 2009 International Students and Young Scientists Workshop "Photonics and Microsystems". IEEE, 2009. http://dx.doi.org/10.1109/stysw.2009.5470315.

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Nalimova, Svetlana S., Aleksander A. Maximov, Vyacheslav A. Moshnikov, Anton A. Bobkov, Dmitriy S. Mazing, Andrei A. Ryabko, Ekaterina A. Levkevich, and Anastasia A. Semenova. "Synthesis and Study of Zinc Oxide Layers Sensitized by Colloidal Nanocrystals." In 2019 IEEE International Conference on Electrical Engineering and Photonics (EExPolytech). IEEE, 2019. http://dx.doi.org/10.1109/eexpolytech.2019.8906789.

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Ye Feng Yang, Yi Zheng Jin, Zhi Zhen Ye, and Hai Ping He. "Dopant induced shape evolution of colloidal nanocrystals: The case of zinc oxide." In 2010 IEEE 3rd International Nanoelectronics Conference (INEC). IEEE, 2010. http://dx.doi.org/10.1109/inec.2010.5425122.

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Chen Feng, Wenbo Bu, and Jianlin Shi. "A more efficient pathway for synthesis of zinc-doped superparamagnetic iron oxide nanocrystals with enhanced saturation magnetization." In 2010 IEEE 3rd International Nanoelectronics Conference (INEC). IEEE, 2010. http://dx.doi.org/10.1109/inec.2010.5424724.

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LaBrie, Russell J., Jorge Padilla, and Van P. Carey. "Experimental Study of Aqueous Binary Mixture Droplet Vaporization on Nanostructured Surfaces." In ASME 2015 International Technical Conference and Exhibition on Packaging and Integration of Electronic and Photonic Microsystems collocated with the ASME 2015 13th International Conference on Nanochannels, Microchannels, and Minichannels. American Society of Mechanical Engineers, 2015. http://dx.doi.org/10.1115/ipack2015-48153.

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In this study heat transfer due to vaporization is investigated for low concentration binary mixtures of 2-propanol/water on nanostructured surfaces. The surfaces are comprised of zinc oxide (ZnO) nanocrystals grown by hydrothermal synthesis on a smooth copper substrate having an average roughness of 0.06 μm. Three nanostructured surfaces used in this study differ only in the duration of the hydrothermal synthesis consisting of 4, 10, and 24 hours of surface growth. Surface geometries were observed to be a function of hydrothermal synthesis time with an increase in area coverage, length, and diameter of nanocrystals with increase synthesis time. ZnO nanocrystals exhibit mean diameter of 500–700 nm, mean length of 1.7–3.3 μm and porosities of 0.04–0.58. Individual droplets between 2.5–3.9 mm in diameter consisting of a binary mixture of 2-propanol/water with concentration of either 0.01 M or 0.03 M were deposited at a minimum distance above the surface that would be sufficient for droplets to detach on their own due to gravity onto a nanostructured surface at temperatures between 110–140 °C. High speed video was used to record the deposition and vaporization process and through image analysis it was possible to measure heat transfer coefficients based on the wetted area, as well as other parameters. Through the video analysis it was observed that droplets which are approximately spherical, impact the surface and spread into a thin film with mean film thickness between 65–400 μm which then evaporated by film evaporation without nucleate boiling. Wettability of each of the surfaces was characterized through contact angle measurements from photographs of the droplet profile when the droplet profile was discernible. When profiles were not discernible due to hydrophilicity of some surfaces, contact angles were calculated by utilizing droplet volume and spread area. Contact angle measurements were performed on the surfaces before and after each experiment in order to document changes in wettability as a result of experimentation. Results from this experiment are compared to water droplet vaporization results from a previous experiment in order to determine whether 2-propanol enhances the heat transfer, and found that the heat transfer coefficient was increased by up to 128% in some cases. Heat transfer enhancement was found to be a function of droplet diameter as well as mixture concentration with 3.9 mm 0.01 M 2-propanol/water droplets showing larger enhancement. Potential uses of heat transfer in this application are also discussed.

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Kang, Ki Moon, Hyo-Won Kim, Il-Wun Shim, and Ho-Young Kwak. "Syntheses of Specialty Nanomaterials at the Multibubble Sonoluminescence Condition." In ASME 2008 International Mechanical Engineering Congress and Exposition. ASMEDC, 2008. http://dx.doi.org/10.1115/imece2008-68320.

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In recent years, a large number of nano-size semiconductors have been investigated for their potential applications in photovoltaic cells, optical sensor devices, and photocatalysts [1, 2, 3]. Nano-size semiconductor particles have many interesting properties due mainly to their size-dependent electronic and optical properties. Appropriately, many speciality of nanomaterials such as CdS and ZnS semiconductor particles, and other metal oxides such as ZnO and lithium-titanate oxide (LTO) have been prepared. However, most of them were prepared with toxic reactants and/or complex multistep reaction processes. Particularly, it is quite difficult to produce LTO nanoparticles, since it typically requires wearisome conditions such as very high temperature over 1000 °C, long producing times, and so on. To overcome such problems, various core/shell type nanocrystals were prepared through different methods such as the hydrothermal synthetic method, microwave, and sonochemistry. Also many coating methods on inorganic oxide nanoparticles were tried for the preparations of various core-shell type nanocrystals. Sonoluminescence (SL) is a light emission phenomenon associated with the catastrophic collapse of a gas bubble oscillating under an ultrasonic field [4]. Light emission of single bubble sonoluminescence (SBSL) is characterized by picosecond flashes of the broad band spectrum extending to the ultraviolet [5, 6]. The bubble wall acceleration has been found to exceed 1011 g at the moment of bubble collapse. Recently observed results of the peak temperature and pressure from the sonoluminescing gas bubble in sulfuric acid solutions [9] were accurately predicted by the hydrodynamic theory for sonoluminescence phenomena [7, 10, 11, 12], which provides a clue for understanding sonochemical reactions inside the bubble and liquid layer adjacent to the bubble wall. Sonochemistry involves an application of sonoluminescence. The intense local heating and high pressure inside the bubbles and liquid adjacent bubble wall from such collapse can give rise to unusual effects in chemical reactions. The estimated temperature and pressure in the liquid zone around the collapsing bubble with equilibrium radius 5 μm, an average radius of bubbles generated in a sonochemical reactor at a driving frequency of 20 kHz with an input power of 179 W, is about 1000 °C and 500 atm, respectively. At the proper condition, a lot of transient bubbles are generated and collapse synchronistically to emit blue light when high power ultrasound is applied to liquid, and it is called multibubble sonoluminescence (MBSL). Figure 1 shows an experimental apparatus for MBSL with a cylindrical quartz cell, into which a 5 mm diameter titanium horn (Misonix XL2020, USA) is inserted [13]. The MBSL facilitates the transient supercritical state [14].in the liquid layer where rapid chemical reactions can take place. In fact, methylene blue (MB), which is one of a number of typical textile dyestuffs, was degraded very fast at the MBSL condition while MB does not degrade under simple ultrasonic irradiation [13]. MBSL has been proven to be a useful technique to make novel materials with unusual properties. In our study, various metal oxides such as ZnO powder [15], used as a primary reinforcing filler for elastomer, homogeneous Li4Ti5O12 nanoparticles [16], used for electrode materials, and core/shell nanoparticles such as CdS coating on TiO2 nanoparticles [17] and ZnS coating on TiO2 nanoparticles [18], which are very likely to be useful for the development of inorganic dye-sensitized solar cells, were synthesized through a one pot reaction under the MBSL condition. Figure 2 shows the XRD pattern of ZnO nanoparticles synthesized from zinc acetate dehydrate (Zn(CH3CO2)2 · 2H2O, 99.999%, Aldrich) in various alcohol solutions with sodium hydroxide (NaOH, 99.99%, Aldrich) at the MBSL condition. The XRD patterns of all powers indicate hexagonal zincite. The XRD pattern for the ZnO nanoparticles synthesized is similar to the ZnO powder produced by a modified sol-gel process and subsequent heat treatment at about 600 °C [19] as shown in Fig.3. The average particle diameter of ZnO powder is about 7 nm. A simple sonochemical method for producing homogeneous LTO nanoparticles, as shown schematically in Fig. 4. First, LiOH and TiO2 nanoparticles were used to prepare LiOH-coated TiO2 nanoparticles as shown in Fig.5. Second, the resulting nanoparticles were thermally treated at 500 °C for 1 hour to prepare LTO nanoparticles. Figure 6 shows a high resolution transmission electron microscope image of LTO nanoparticles having an average grain size of 30–40 nm. All the nanoparticle synthesized are very pure in phase and quite homogeneous in their size and shape. Recently we succeeded in synthesizing a supported nickel catalyst such as Ni/Al2sO3, MgO/Al2O3 and LaAlO3, which turned out to be effective for methane decomposition [20]. Sonochemistry may provide a new way to more rapidly synthesize many specialty nanoparticles with less waste [21]. This clean technology enables the preparation of new materials such as colloids, amorphous particles [22], and various alloys.

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