Academic literature on the topic 'Nanomaterials- Semiconductors'

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Journal articles on the topic "Nanomaterials- Semiconductors"

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Zhang, Li-De, and Xiao-Sheng Fang. "Controlled Growth and Characterization Methods of Semiconductor Nanomaterials." Journal of Nanoscience and Nanotechnology 8, no. 1 (January 1, 2008): 149–201. http://dx.doi.org/10.1166/jnn.2008.n02.

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One-dimensional (1D) semiconductor nanomaterials attract much attention because they are ideal systems for investigation and studying the relationship between properties and structures and having extensive application future in the high technical field. They are expected to play an important role in fabrication of the next generation nanocircuits, nanotools, nanowires lasers, photon tunneling devices, near-field photo-waveguide devices, etc. This article described controlled growth, characterization of structures and morphologies and properties of 1D semiconductor nanomaterials based on our previous works. This article is organized into two parts: The first part is complicated nanostructures of semiconductors, which includes coaxial nanocables, heterostructure nanowires and nanowires with metal–semiconductor junction behavior, hierarchical structures, doping of the nanowires and nanobelts, porous materials and periodically twined nanowires and asymmetrical polytypic nanobelts. The second part contains semiconductor nanoarrays based on anodic alumina membrane (AAM) templates. Finally, we propose that further investigation of the influence of nanomaterial morphologies on properties and how to design the morphology of nanostructures to meet the property requirements of nanodevices are our future research directions in this field.
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Dang, Chao, Mingyang Liu, Zhiwei Lin, and Wei Yan. "Selenium nanomaterials enabled flexible and wearable electronics." Chemical Synthesis 3, no. 2 (2023): 14. http://dx.doi.org/10.20517/cs.2022.33.

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Selenium (Se), as an intriguing chalcogenide semiconductor, has traditionally been used for solar energy harvesting. The recent development of nanoscience and nanotechnology has enabled a myriad of Se nanomaterials with compelling structures and unique features. Compared with other chalcogens, Se nanomaterials possess anisotropic crystalline structure, intrinsic chirality, and high reactivity, as well as unique optical, electrical, photoconductive, and piezoelectrical properties. The integration of these Se nanomaterials with technologically important materials, such as conductors and semiconductors, over flexible, bendable, stretchable, and highly curved substrates offer a new generation of Se nanomaterial-based flexible and wearable electronics. In this mini review, we survey the recent scientific and technological breakthroughs in Se nanomaterials-enabled flexible and wearable electronics. We highlight the synthesis, fabrication, morphologies, structure, and properties (optical, electrical, optoelectrical, photovoltaic, and piezoelectric) of Se nanomaterials as well as their integration into innovative functional devices that deliver higher forms of applications across smart sensing, health care, and energy domains. We conclude with a critical analysis of existing challenges and opportunities that will trigger the continued progress of the field.
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Ma, Liang, Shuang Chen, Yun Shao, You-Long Chen, Mo-Xi Liu, Hai-Xia Li, Yi-Ling Mao, and Si-Jing Ding. "Recent Progress in Constructing Plasmonic Metal/Semiconductor Hetero-Nanostructures for Improved Photocatalysis." Catalysts 8, no. 12 (December 7, 2018): 634. http://dx.doi.org/10.3390/catal8120634.

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Hetero-nanomaterials constructed by plasmonic metals and functional semiconductors show enormous potential in photocatalytic applications, such as in hydrogen production, CO2 reduction, and treatment of pollutants. Their photocatalytic performances can be better regulated through adjusting structure, composition, and components’ arrangement. Therefore, the reasonable design and synthesis of metal/semiconductor hetero-nanostructures is of vital significance. In this mini-review, we laconically summarize the recent progress in efficiently establishing metal/semiconductor nanomaterials for improved photocatalysis. The defined photocatalysts mainly include traditional binary hybrids, ternary multi-metals/semiconductor, and metal/multi-semiconductors heterojunctions. The underlying physical mechanism for the enhanced photocatalysis of the established photocatalysts is highlighted. In the end, a brief summary and possible future perspectives for further development in this field are demonstrated.
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Lu, Yuzheng, Youquan Mi, Junjiao Li, Fenghua Qi, Senlin Yan, and Wenjing Dong. "Recent Progress in Semiconductor-Ionic Conductor Nanomaterial as a Membrane for Low-Temperature Solid Oxide Fuel Cells." Nanomaterials 11, no. 9 (September 3, 2021): 2290. http://dx.doi.org/10.3390/nano11092290.

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Reducing the operating temperature of Solid Oxide Fuel Cells (SOFCs) to 300–600 °C is a great challenge for the development of SOFC. Among the extensive research and development (R&D) efforts that have been done on lowering the operating temperature of SOFCs, nanomaterials have played a critical role in improving ion transportation in electrolytes and facilitating electrochemical catalyzation of the electrodes. This work reviews recent progress in lowering the temperature of SOFCs by using semiconductor-ionic conductor nanomaterial, which is typically a composition of semiconductor and ionic conductor, as a membrane. The historical development, as well as the working mechanism of semiconductor-ionic membrane fuel cell (SIMFC), is discussed. Besides, the development in the application of nanostructured pure ionic conductors, semiconductors, and nanocomposites of semiconductors and ionic conductors as the membrane is highlighted. The method of using nano-structured semiconductor-ionic conductors as a membrane has been proved to successfully exhibit a significant enhancement in the ionic conductivity and power density of SOFCs at low temperatures and provides a new way to develop low-temperature SOFCs.
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Cai, Jiabai, and Shunxing Li. "Photocatalytic Treatment of Environmental Pollutants using Multilevel- Structure TiO2-based Organic and Inorganic Nanocomposites." Current Organocatalysis 7, no. 3 (November 30, 2020): 161–78. http://dx.doi.org/10.2174/2213337207999200701214637.

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Nanostructured materials often exhibit unique physical properties, such as fast carrier transport, subwavelength optical waveguiding, and a high surface-area-to-volume ratio. When the size of a material is reduced to nanoscale dimensions, its physical and chemical properties can change dramatically. In addition, nanostructures offer exciting new opportunities for environmental applications. In this review, we aim to provide an up-to-date summary of recent research related to multifunctional TiO2-based inorganic and organic semiconductor nanomaterials, covering both their synthesis and applications. After a brief introduction of the definition and classification of TiO2-based inorganic and organic semiconductor nanomaterial structures, we discuss various application strategies, such as sewage treatment, heavy metal removal, and the oxidation of alcohols to the corresponding aldehydes. In our previous work, we fabricated a variety of TiO2-based hollow spheres using a diverse range of materials from inorganic semiconductors to organic semiconductors and applied these structures as photocatalysts. Further, the development of these nanostructures may enable numerous applications in the field of environmental technology.
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Zhu, Hongliang, Li Fan, Kaili Wang, Hao Liu, Jiawei Zhang, and Shancheng Yan. "Progress in the Synthesis and Application of Tellurium Nanomaterials." Nanomaterials 13, no. 14 (July 12, 2023): 2057. http://dx.doi.org/10.3390/nano13142057.

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In recent decades, low-dimensional nanodevices have shown great potential to extend Moore’s Law. The n-type semiconductors already have several candidate materials for semiconductors with high carrier transport and device performance, but the development of their p-type counterparts remains a challenge. As a p-type narrow bandgap semiconductor, tellurium nanostructure has outstanding electrical properties, controllable bandgap, and good environmental stability. With the addition of methods for synthesizing various emerging tellurium nanostructures with controllable size, shape, and structure, tellurium nanomaterials show great application prospects in next-generation electronics and optoelectronic devices. For tellurium-based nanomaterials, scanning electron microscopy and transmission electron microscopy are the main characterization methods for their morphology. In this paper, the controllable synthesis methods of different tellurium nanostructures are reviewed, and the latest progress in the application of tellurium nanostructures is summarized. The applications of tellurium nanostructures in electronics and optoelectronics, including field-effect transistors, photodetectors, and sensors, are highlighted. Finally, the future challenges, opportunities, and development directions of tellurium nanomaterials are prospected.
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Feliczak-Guzik, Agnieszka. "Nanomaterials as Photocatalysts—Synthesis and Their Potential Applications." Materials 16, no. 1 (December 25, 2022): 193. http://dx.doi.org/10.3390/ma16010193.

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Increasing demand for energy and environmental degradation are the most serious problems facing the man. An interesting issue that can contribute to solving these problems is the use of photocatalysis. According to literature, solar energy in the presence of a photocatalyst can effectively (i) be converted into electricity/fuel, (ii) break down chemical and microbial pollutants, and (iii) help water purification. Therefore, the search for new, efficient, and stable photocatalysts with high application potential is a point of great interest. The photocatalysts must be characterized by the ability to absorb radiation from a wide spectral range of light, the appropriate position of the semiconductor energy bands in relation to the redox reaction potentials, and the long diffusion path of charge carriers, besides the thermodynamic, electrochemical, and photoelectrochemical stabilities. Meeting these requirements by semiconductors is very difficult. Therefore, efforts are being made to increase the efficiency of photo processes by changing the electron structure, surface morphology, and crystal structure of semiconductors. This paper reviews the recent literature covering the synthesis and application of nanomaterials in photocatalysis.
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BARDUS, I., S. KOVACHОV, I. BOHDANOV, and Y. SUCHIKOVA. "PROFESSIONAL COMPETENCE OF A SPECIALIST IN THE FIELD OF NANOMATERIAL SCIENCE TO CREATE INNOVATIVE NANOSTRUCTURES ON THE SURFACE OF SEMICONDUCTORS." Scientific papers of Berdiansk State Pedagogical University Series Pedagogical sciences 1, no. 3 (December 7, 2022): 237–48. http://dx.doi.org/10.31494/2412-9208-2022-1-3-237-248.

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The article is devoted to the urgent problem of improving the quality of professional training of future specialists in the field of nanomaterial science for productive activities, namely, the definition of the system of his professional competence in the creation of nanostructures on the surface of semiconductors. The article, based on the structure of the production process for the synthesis of innovative nanostructures on the surface of a semiconductor, defines the qualification requirements for a specialist in the field of nanomaterial science. It was established that a specialist in the field of nanomaterial science must possess design, technological, operational, research, organizational and management competencies. Design competence involves the modeling of a new nanostructure on the surface of a semiconductor to acquire the desired functional properties, the selection of optimal technological solutions for the synthesis of these nanostructures, and the development of experimental methods in accordance with the chosen technology. Technological competence ensures the effectiveness of professional activity in the synthesis of a new nanostructure on the surface of a semiconductor based on the chosen technology. Organizational and managerial competence allows a specialist to carry out technical training, control, and regulation of the process of synthesis of nanostructures on the surface of a semiconductor with a given quality. The formed scientific and research competence allows to carry out a scientific search for the morphological properties of the nanomaterial structure in order to give it the necessary functional properties, to develop new technologies and appropriate equipment for the synthesis of nanostructures on the surface of a semiconductor. The article also describes the structure and content of design, technological, research and organizational and management competencies of specialists in the field of nanomaterial science, which are the basis for the development of a fundamentalized system of their training in institutions of higher education. Key words: nanotechnology, professional competence, production process, system approach, specialist in the field of nanomaterial science, productive activity, synthesis of nanomaterials.
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Mintcheva, Neli, Shigeru Yamaguchi, and Sergei A. Kulinich. "Hybrid TiO2-ZnO Nanomaterials Prepared Using Laser Ablation in Liquid." Materials 13, no. 3 (February 5, 2020): 719. http://dx.doi.org/10.3390/ma13030719.

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Hybrids of semiconductor nanomaterials often demonstrate properties that are superior to those of their components. In this study, we prepared hybrid nanomaterials of TiO2 and ZnO, which are among the most actively studied semiconductors, by means of millisecond-pulsed laser and analyzed how their morphology, particle size, and surface composition depend on preparation conditions. A series of nanomaterials were obtained via sequentially ablating Zn and Ti metal plates (in different sequences) in water, while laser pulses of lower (2.0 J/pulse) and higher (5.0 J/pulse) energy were applied. The properties of laser-produced hybrid TiO2-ZnO nanomaterials were shown to be governed by experimental conditions such as laser pulse width, pulse peak power, and reaction media (either pure water or colloid with nanoparticles). The morphology revealed nanospheres of TiO2 that decorate nanorods of ZnO or flower-like aggregates of zinc oxide. Intriguingly, after extended ablation time, titania was found to be self-doped with Ti3+ and Ti2+ ions, and the contribution of lower oxidation states of titanium could be controlled by the applied laser pulse energy. The physicochemical characteristics of hybrid nanomaterials were compared with pure ZnO and TiO2 prepared under the same laser conditions.
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D., Nirmal. "HIGH PERFORMANCE FLEXIBLE NANOPARTICLES BASED ORGANIC ELECTRONICS." December 2019 2019, no. 02 (December 24, 2019): 99–106. http://dx.doi.org/10.36548/jei.2019.2.005.

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The attributes of the organic materials have made them more prominent in a wide range of applications engaged for large or small purpose such as the solar cells or the displays in the mobile devices. The solar cells developed using the organic semiconductors are more advantageous due to their flexibility and their easy installation. Despite the versatile nature of the and easy implementation the organic semiconductors still suffers from low efficiency in term of cost, performance and size. The proposed method incorporates the nanomaterials in the organic solar cell to improvise efficiency (performance) and to minimize the cost as well as the size of the solar cells. The proposed method replaces the semiconductor that is organic by incorporating the organic semiconductors with the nanoparticle additives to have a perfect blending in solution to improve the crystallizations of the semiconductor, and the uniformity thus improvising the power conversion efficiency in the solar cells and minimizing the size and the cost . The result acquired through evaluation proves the performance improvements to 19% form 3.5% in the solar cells.
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Dissertations / Theses on the topic "Nanomaterials- Semiconductors"

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Cozzarini, Luca. "Nanomaterials based on II-VI Semiconductors." Doctoral thesis, Università degli studi di Trieste, 2012. http://hdl.handle.net/10077/7359.

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2010/2011
This thesis describes: (i) synthesis and characterization of colloidal nanocrystals of II-VI semiconductor compounds; (II) development of two novel materials using such nanocrystals as “building blocks”: (IIa) a nanocrystals/polymer composite, to be used as phosphor in LED-based lighting devices; (IIb) an inorganic, nano-structured multiphase material, showing a promising geometry as an electronic intermediate band material. Different typologies of nanocrystals (single-phase, alloyed or core-shells) were successfully synthesized using air-stable, safe reagents. Their optical properties (absorption spectrum, fluorescence wavelength and fluorescence quantum yield) were mapped as function of different parameters. Good results in engineering optical properties were achieved by: (a) changing size and/or composition in single-phase nanocrystals; (b) tuning shell composition and thickness and/or mutually diffusing one material into the other in multi-phase nanocrystals. The influence of different surface ligands on optical properties and on solubility in different media was also studied. Nanocrystal/polymer composite lenses were obtained from nanocrystals with desired fluorescence wavelength and quantum yield, mixed in an appropriate solvent with polymer pellets. The mixture was drop casted or tape casted on a solid substrate, obtaining solid, transparent lenses after solvent evaporation. A nano-structured, all-inorganic material (composed of semiconducor nanocrystals embedded into a wider bandgap semiconductor) was obtained through self-assembly and densification of colloidal core-shells nanocrystals. The realization of this composite supracrystal was achieved via a multi-step process: (i) colloidal synthesis of core-shell nanocrystals; (ii) surface ligands exchange; (iii) assembly; (iv) heat treatment. Evolution of the optical properties during heat treatment suggests that it is possible to sinter the shell material without altering the internal nano-heterostructure, if temperature and time of the treatment are controlled properly.
In questa tesi sono descritti: (I) la sintesi colloidale e la caratterizzazione di nanocristalli di semiconduttori II-VI; (II) lo sviluppo, utilizzando i suddetti nanocristalli quali “unità da costruzione”, di due materiali innovativi: (IIa) un composito nanocristalli/polimero, da usare come fosforo in dispositivi per illuminazione basati su LED; (IIb) un materiale inorganico nano-strutturato multifase, con una geometria promettente quale materiale a banda elettronica intermedia. Differenti semiconduttori II-VI sono stati sintetizzati in forma di nanocristalli (monofasici, in forma di lega o in struttura di tipo “core-shell”) usando reagenti sicuri e stabili in atmosfera. Le loro proprietà ottiche (spettro di assorbimento, lunghezza d’onda di fluorescenze e resa quantica di fluorescenza) sono state mappate in funzione di numerosi parametri. Sono stati raggiunti ottimi risultati nel controllo delle proprietà ottiche sia in nanocristalli a fase singola (modificandone le dimensioni o la composizione chimica) che in nanocristalli multifase (regolandone la composizione e lo spessore della “shell”, nonché mutualmente diffondendo un materiale nell’altro). È stata anche studiata l’influenza di differenti leganti superficiali sulle proprietà ottiche e sulla solubilità dei nanocristalli in differenti solventi. Lenti composite di nanocristalli/polimero sono state ottenute a partire da nanocristalli aventi la lunghezza d’onda e la resa quantica di fluorescenza desiderate, mescolandoli con pellet di polimero in solventi appropriati. La miscela è stata depositata su un supporto, tramite drop casting o tape casting, ottenendo lenti solide trasparenti dopo l’evaporazione del solvente. Un materiale inorganico nano strutturato (costituito da nanocristalli di semiconduttore racchiusi all’interno di un secondo materiale semiconduttore a bandgap maggiore) è stato ottenuto tramite l’autoassemblaggio e la densificazione di nanocristalli core-shell sintetizzati con procedure di chimica colloidale. La realizzazione di suddetto sovra-cristallo si è svolta in più fasi: (i) sintesi colloidale; (ii) sostituzione dei leganti superficiali; (iii) assemblaggio; (iv) trattamento termico. I risultati derivanti dallo studio dell’evoluzione delle proprietà ottiche durante il trattamento termico suggeriscono che sia possibile sinterizzare il materiale della shell senza alterare la nano-eterostruttura interna, se la temperatura e il tempo del trattamento sono scelti opportunamente.
XXIV Ciclo
1983
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Tassi, Nancy Gattuso. "Manipulation of organic nanomaterials." Access to citation, abstract and download form provided by ProQuest Information and Learning Company; downloadable PDF file, 51 p, 2008. http://proquest.umi.com/pqdweb?did=1459918081&sid=5&Fmt=2&clientId=8331&RQT=309&VName=PQD.

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Zhang, Shaolin. "Wide band gap nanomaterials and their applications." Click to view the E-thesis via HKUTO, 2009. http://sunzi.lib.hku.hk/hkuto/record/B41758225.

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Berestok, Taisiia. "Assembly of colloidal nanocrystals into porous nanomaterials." Doctoral thesis, Universitat de Barcelona, 2018. http://hdl.handle.net/10803/663275.

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This thesis focuses on different aspects of NCs colloidal synthesis, the exploration of the relevant surface chemistries that afford NC assembly and the NC implementation into porous nanomaterials. The work is divided into two blocks. The first block is devoted to developing and optimizing the synthesis of NCs followed by the examination of their suitability for potential applications in catalysis and photocatalysis. The second block is dedicated to establish procedures to fabricate single-component or multicomponent porous nanomaterials from NC building blocks. To embrace the use of the developed strategies in different application fields, several kind of materials were under research. Namely, metals (e.g. Au), metal oxides (e.g. CeO2, TiO2, Fe2O3), metal chalcogenides (e.g. In2S3, ZnS, PbS, CuGaS2 and Cu2ZnSnSe4), and their composites. CeO2 NCs synthesis was deeply investigated with the aim to achieve a proper control on the NCs morphology, facets exposed, crystal phase, composition, etc., required for application. Overall, CeO2 NCs with spherical, octapod-like branched, cubic hyperbranched, and kite-like morphology with sizes in the range 7 to 45 nm were produced by adjusting experimental conditions of the synthetic protocol. Branched and hyperbranched NCs showed higher surface areas, porosities and oxygen capacity storage values compared to quasi-spherical NCs. The NCs morphology-controlled synthesis has been extended to quaternary Cu2ZnSnSe4 (CZTSe). CZTSe NCs with narrow size distribution and controlled composition were produced. It was shown how off-stoichiometric CZTSe compositions were characterized by higher charge carrier concentrations and thus electrical conductivities. The strategy to functionalize the metal oxide NC surface composition by applying different ligands is proposed. This enables to develop a novel approach to assemble metal oxide NCs into porous gel and aerogel structures. Propylene oxide has been found to trigger the gelation process of glutamine functionalized NCs. The detailed investigation of the gelation mechanism is demonstrated for the case of ceria. The method is applied for NCs with different morphologies. Eventually, the versatility of the concept is proved by using of the proposed approach for the TiO2 and Fe2O3 nanocrystals. The assembly method has been extended to metal chalcogenides - In2S3 NCs - starting from the NCs synthesis, with further surface chemistry manipulation and eventually follows by the NC assembly into gels and aerogels. The optimization of NC surface chemistry was achieved by testing different ligand exchange approaches via applying short-chain organic and inorganic ligands. The assembly method based on ligand desorption from the NC surface and chalcogenide-chalcogenide bond formation has been established for In2S3. The comparison of the different ligands impact on the NC performance in colloidal form, when assembled into gels and when supported onto substrate is investigated towards photoelectrocatalysis. The oxidative ligand desorption assembly approach has been extended for multicomponent NCs for the case of CuGaS2 and CuGaS2-ZnS. Optimization of spin-coating process of the formed NCs inks followed by applying of sol-gel chemistry led to formation of highly porous layers from TGA-CuGaS2 and TGA-ZnS. Applied results of CuGaS2/ZnS nanocrystal-based bilayers and CuGaS2–ZnS nanocrystal-based composite layers have been shown by testing their photoelectrochemical energy conversion capabilities. The approach to adjust NC surface chemistry has been proposed and tested for performing multicomponent NC assemblies. Applying of different ligands for NC surface functionalization endows their surface with different charges which usually provides colloidal NCs stabilization. It has been found that mixing of oppositely charged NCs with certain concentration enabled their assembly/gelation via electrostatic interaction. The proposed approach has been applied and optimized to produce multicomponent NC gels and aerogels. The detailed investigation of the gelation mechanism is shown for combination of metal-metal oxide and metal oxide-metal chalcogenide NCs (Au-CeO2, CeO2-PbS). Applied results of the Au-CeO2 aerogels were demonstrated for CO-oxidation.
Esta tesis se centra en la síntesis coloidal de nanocristales (NCs), en la exploración de su química de superficie y en su ensabanado en nanomateriales porosos funcionales. Para demostrar la versatilidad de aplicación de dichas estructuras, en este estudio se han considerado NCs de distintos tipos de materiales: metales (Au), óxidos metálicos (CeO2, TiO2, Fe2O3), calcogenuros metálicos (In2S3, ZnS, PbS, CuGaS2,Cu2ZnSnSe4) y sus materiales compuestos. El trabajo se dividió en dos bloques. En el primero se desarrolló y optimizó la síntesis de NCs de óxidos y calcogenuros metálicos y se evaluó su potencial para aplicaciones de catálisis y fotocatálisis. Se investigó en profundidad la síntesis de NCs de CeO2, poniendo énfasis en controlar su morfología. Se consiguió producir NCs de CeO2 de forma controlada (esférica, octapodo ramificado, cúbico ramificado y romboidal) y con tamaño controlado (7-45 nm). Asimismo, se obtuvieron NCs de Cu2ZnSnSe4 con una fina distribución de tamaños y composición controlada. En el segundo bloque se establecieron y estudiaron procedimientos para fabricar nanomateriales porosos mono- o multicomponentes a partir del ensamblado de NCs. Se desarrolló una estrategia basada en el ajuste de la química de superficie de NCs de óxidos metálicos (CeO2, Fe2O3,TiO2) y de calcogenuros metálicos (In2S3, CuGaS2-ZnS) que permitió su ensamblaje controlado en estructuras porosas de tipo gel y aerogel. En el caso de los óxidos metálicos, se determinó que el ensamblado se inicia con la adición de un epóxido a NCs funcionalizados con glutamina, causando la gelación. La desorción oxidativa de ligandos basada en la formación de enlaces calcogenuro-calcogenuro se propuso como mecanismo de gelación en calcogenuros mono- (In2S3) y multicomponente (CuGaS2-ZnS). Se investigó el impacto del empleo de distintos ligandos en la eficiencia foto-electrocatalítica de NCs en forma coloidal, ensamblados en geles y soportados en sustratos. Se desarrolló y estudió el ajuste de la química de superficie de NCs para la obtención de ensamblajes multicomponente mediante interacción electrostática de coloides en suspensión. El mecanismo de gelación fue investigado al detalle para materiales compuestos de NCs de oxido metálico (CeO2) con NCs de óxido de calcogenuro (PbS-CeO2) y metálicos (Au-CeO2). Los aerogeles de Au-CeO2 demostraron potencial para la oxidación de CO.
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Zhang, Shaolin, and 張少林. "Wide band gap nanomaterials and their applications." Thesis, The University of Hong Kong (Pokfulam, Hong Kong), 2009. http://hub.hku.hk/bib/B41758225.

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Yu, Zhang. "Solution Processed Chalcogenide Nanomaterials for Thermoelectric Application." Doctoral thesis, Universitat de Barcelona, 2021. http://hdl.handle.net/10803/670923.

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The bottom-up engineering of nanomaterials using solution-processing strategies is of particular interest for reducing cost and optimizing the performance of TE materials and devices. This thesis focuses on the development of scalable methods for the production of TE nanomaterials with optimized performance. The thesis is divided into 5 chapters. Chapter 1 introduces solution-based approaches for producing functional nanomaterials and the general state of the art in the field of thermoelectricity. Chapter 2 and chapter 3 present a fast and simple molecular ink-based method to produce low cost and crystallographically textured SnSe2 and SnSe nanomaterials. Molecular ink printing techniques could offer a scalable approach to fabricate TE devices on flexible substrates. In these chapters, I proved that cost-effective p-type SnSe NPLs could be produced by a molecular ink-based strategy that allowed introducing controlled amounts of Te to achieve unprecedentedly high TE figure of merit. On the other hand, n-type SnSe2 nanomaterials were also intentionally produced from the same strategy to complement an all Sn-Se based device. Both of the bulk nanomaterials displayed significant crystallographic texture after hot pressing, resulting in highly anisotropic charge and heat transport properties. Different approaches were applied to optimize their TE performance: SnSe2 NPLs were blended with metal NPs to produce a metal-semiconductor NC. The electrical conductivities of the blends were significantly improved with respect to bare SnSe2 bulk nanomaterial and a three-fold increase in the TE figure of merit was obtained, reaching unprecedented values up to ZT = 0.65 for SnSe2 material. For SnSe nanomaterials, I demonstrate that the introduction of small amounts of tellurium in the precursor ink allowed reducing the band gap, increasing both charge carrier concentration and mobility, especially cross plane, with a minimal decrease of the Seebeck coefficient. This strategy translated into record out of plane ZT values at 800 K, ZT=1.05 Chapter 4 and chapter 5 describe two different strategies to produce Bi2Te3-Cu2-xTe NCs based on the consolidation of nanostructured building blocks. I first detail a two-step solution-based process to produce the Bi2Te3-Cu2-xTe heteronanostructures, based on the growth of Cu2-xTe nanocrystals on the surface of Bi2Te3 nanowires. The transport properties of the NCs are investigated as a function of the amount of Cu introduced, which reveal that the presence of Cu decreases the material thermal conductivity through promotion of phonon scattering, modulates the charge carrier concentration through electron spillover, and increases the Seebeck coefficient through filtering of charge carriers at energy barriers. These effects result in an improvement of over 50% of the TE figure of merit of Bi2Te3. As comparison, I produced Bi2Te3-Cu2-xTe NCs by directly mixing proper ratio of individual Bi2Te3 nanowires with Cu2-xTe nanocubes and consolidating the resulting NP mixture by hot-press. A significant difference of transport properties was detected when compared with NCs fabricated by hot-pressing heterostructured Bi2Te3-Cu2-xTe nanowires. On the contrary to the composite obtained from hetero- nanostructures, the presence of Cu2-xTe nanodomains did not lead to a significant reduction of the lattice thermal conductivity of the reference Bi2Te3, which is already very low here, but it resulted in a nearly threefold increase of its power factor. Additionally, the presence of Cu2-xTe resulted in a strong increase of the Seebeck coefficient. This increase is related to the energy filtering of charge carriers at energy barriers within Bi2Te3 domains created by the accumulation of electrons in the regions nearby Cu2-xTe/Bi2Te3 junctions. Overall, a significant improvement of figure of merit, up to a 250%, was obtained with the suitable combination of Cu2-xTe NPs and Bi2Te3 nanowires. Finally, the main conclusions of this thesis and some perspectives for future work are presented.
La ingeniería de nanomateriales a partir del procesado en solución es de particular interés para optimizar el rendimiento de los materiales y dispositivos termoeléctricos. . Esta tesis estáse centra en el diseño y el ensamblaje racional de nanomateriales termoeléctricos de alto rendimiento a través de procesado en solución. La tesis se divide en 5 capítulos. El Capítulo 1 aborda la introducción fundamental del enfoque sintético para producir nanomateriales funcionales. Los capítulos 2 y 3 presentan un método rápido y simple basado en soluciones para producir nanomateriales SnSe2 y SnSe con textura cristalográfica. Dado que los calcogenuros de estaño son materiales especialmente interesantes para la conversión de energía termoeléctrica, se sintetizaron nanoplacas SnSe y SnSe2 controlables por forma mediante una estrategia basada en tinta molecular para lograr una figura de mérito termoeléctrica sin precedentes por dopaje con Te/Cu. Ambos nanomateriales mostraron una textura cristalográfica significativa después del prensado en caliente, lo que dio como resultado unas propiedades de transporte de carga calor altamente anisotrópicas. Los capítulos 4 y 5 describen dos estrategias diferentes para producir nanocompuestos Bi2Te3-Cu2-xTe basados en la consolidación de nanoestructuras. La presencia de Cu2-xTe da como resultado un fuerte aumento del coeficiente de Seebeck. Este aumento está relacionado con el filtrado de los portadores de carga en función de su energía en las barreras de energía dentro de los dominios Bi2Te3 creados por la acumulación de electrones en las regiones cercanas a las uniones Cu2-xTe / Bi2Te3. En general, se obtiene una mejora significativa de la figura de mérito con nanocompuestos Bi2Te3-Cu2-xTe. Finalmente, en el último capítulo se presentan las principales conclusiones de esta tesis y algunas perspectivas para trabajos futuros.
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Liu, Yu. "Bottom-up Engineering of Chalcogenide Thermoelectric Nanomaterials." Doctoral thesis, Universitat de Barcelona, 2018. http://hdl.handle.net/10803/663274.

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In this thesis, it is detailed the bottom-up production and characterization of thermoelectric (TE) nanomaterials with significant enhanced performance by using colloidal nanocrystals (NCs) as building blocks. The production of TE nanomaterials with significant improved figure of merit (ZT), has to do, not only with the precise control of the NCs properties, but also with the further fine control over the crystallographic alignment of nanograins of highly anisotropic materials. The first part of the thesis correspond to the study of synthetic routes to produce high quality chalcogenide NCs that are doped during the NC synthesis, in order to control the charge carrier concentration. The system studied was I−V−VI chalcogenide semiconductor, specifically it was produced the materials: AgSbSe2 and Cu3SbSe4. A low-cost, high-yield and scalable synthesis route to produce monodisperse of AgSbSe2 and Cu3SbSe4 NCs was obtained. After ligand displacement, the NCs were used as building blocks to produce TE nanomaterials. Additionally, by means of substitutional doping, a large increment in the power factor and relatively lower thermal conductivities were observed. The optimization of the doping concentration resulted in ZT values of 1.10 at 640 K for AgSb0.98Bi0.02Se2, and of 1.26 at 673 K for Cu3Sb0.88Sn0.10Bi0.02Se4, which represents a significant increase beyond the state of the art in Te-free multinary Ag/Cu-based chalcogenide materials. In the second part of the thesis, the work about PbS-metal (Cu and Sn) nanocomposites produced by blending procedure is presented. The low work function metal is able to inject electrons to the intrinsic PbS matrix, which is another strategy to control the charge carrier concentration. The power factor is dramatically enhanced due to the increase of the electrical conductivity in the nanocomposites. Consequently, the ZTmax was remarkably enhanced by two times as compared with the pristine PbS. Furthermore, we also compared the TE performance of microcrystalline composites with the same composition as in nanocrystalline composites; commercial PbS host with Cu particles. The results revealed that with the same metal addition, higher electrical conductivities were obtained in the nanocomposite, but higher Seebeck coefficients were maintained in the microcomposite. Moreover, higher thermal conductivities were also obtained in the microcomposite. Finally, the figure of merit ZT were higher for the microcomposite system in the low temperature range, but much lower in the higher temperature range compared with the nanocomposites system. In the last block, the process of production of crystallographically textured materials is presented. We face here the challenge of bottom-up approaches to control the crystallographic alignment of nanograins. The production of nanostructured Bi2Te3-based alloys is presented. This can be done with controlled stoichiometry by solution-processing, and crystallographic texture by liquid-phase sintering using multiple pressure and release steps at 480 °C, above the tellurium melting point. Additionally, we explain the possible mechanism to produce the highly textured nanomaterials. This strategy results in record TE figures of merit: ZT=1.83 at 420 K for Bi0.5Sb2.5Te3 and ZT=1.31 for Bi2Te2.7Se0.3 at 440 K when averaged over 5 materials in the c direction, respectively. These high figures of merit extended over a wide temperature range, which results in energy conversion efficiencies a 50% higher than commercial ingots in the similar temperature range. In summary, different strategies to improve the TE performance of bulk nanostructured materials produced by bottom-up engineering of NCs, have been studied and confirmed in this thesis. Additionally, it has been proven that the solution-processed synthesis approach is low-cost, compatible with the scale-up engineering, and also versatile in tuning the size, shape, composition, and microstructure, among others parameters of different nanomaterials to optimize their TE properties.
Los nanocristales (NCs) coloidales tienen excelentes propiedades para diferentes aplicaciones, como la conversión de energía, la catálisis, los dispositivos electrónicos y optoelectrónicos, entre otros. Así mismo, la síntesis coloidal de NCs tiene ventajas en el control del tamaño, forma y composición a nivel de la nanoescala; las bajas temperaturas de reacción; y la no necesidad de equipos especializados. Este proyecto se concentra en el diseño racional y la ingeniería de materiales termoeléctricos (TE) nanoestructurados de alta eficiencia, usando la estrategia del ensamblado ascendente (bottom-up) de NCs coloidales. Primero, se diseñó una ruta de síntesis de bajo costo, alto rendimiento, con la cual, se obtuvieron NCs de AgSbSe2 y Cu3SbSe4. La optimización de la concentración de dopaje resultó en valores para la figura de mérito TE, ZT, de 1.10 a 640 K para AgSb0.98Bi0.02Se2, y de 1.26 at 673 K para Cu3Sb0.88Sn0.10Bi0.02Se4. El material con mejores propiedades se usó para la producción de un generador TE en forma de anillo, para acoplarlo a los tubos de escape de gases, obteniendo una potencia eléctrica de 1mW por elemento TE con una diferencia de temperatura de 160 °C. En la segunda parte, se presenta el trabajo de la producción de nanocopuestos de PbS-metal (Cu y Sn) usando un procedimiento versátil de mezcla de NCs. La función de trabajo del metal es capaz de inyectar electrones a la matriz intrínseca de PbS. El factor de potencia TE, se ve dramáticamente incrementado debido al aumento en la conductividad eléctrica en los nanocompuestos TE. Consecuentemente, el valor máximo de ZT se vio excepcionalmente incrementado por el doble del valor comparado con el material original PbS. Finalmente, se presenta el proceso de producción de materiales texturizados cristalográficamente, produciendo materiales tipo p BixSb2-xTe3 y tipo n Bi2Te3-xSex. Se controló la estequiometria durante el procesamiento en solución y la textura cristalográfica, por medio de la sinterización en fase líquida con un procedimiento de múltiples pasos de presión y relajación a una temperatura de 480°C. Los valores de la figura de mérito TE presentan el record de: ZT=1.83 a 420 K para Bi0.5Sb2.5Te3 y ZT=1.31 para Bi2Te2.7Se0.3 a 440 K.
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Cress, Cory D. "Effects of ionizing radiation on nanomaterials and III-V semiconductor devices /." Online version of thesis, 2008. http://hdl.handle.net/1850/6278.

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Hsieh, Chien-Wen. "Formation of composite organic thin film transistors with one-dimensional nanomaterials." Thesis, University of Cambridge, 2011. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.609276.

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Becerril-Garcia, Hector Alejandro. "DNA-Templated Nanomaterials." Diss., CLICK HERE for online access, 2007. http://contentdm.lib.byu.edu/ETD/image/etd1823.pdf.

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Books on the topic "Nanomaterials- Semiconductors"

1

Manasreh, Mahmoud Omar. Introduction to nanomaterials and devices. Hoboken, N.J: Wiley-Interscience, 2012.

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(Society), SPIE, ed. Nanoepitaxy: Homo- and heterogeneous synthesis, characterization, and device integration of nanomaterials : 3-4 August 2009, San Diego, California, United States. Bellingham, Wash: SPIE, 2009.

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Islam, M. Saiful. Nanoepitaxy: Homo- and heterogeneous synthesis, characterization, and device integration of nanomaterials II : 1-2 and 4 August 2010, San Diego, California, United States. Edited by SPIE (Society). Bellingham, Wash: SPIE, 2010.

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Rahimi-Iman, Arash. Semiconductor Photonics of Nanomaterials and Quantum Structures. Cham: Springer International Publishing, 2021. http://dx.doi.org/10.1007/978-3-030-69352-7.

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Semiconductor Nanomaterials. Wiley-VCH Verlag GmbH, 2010.

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Co, Business Communications. Nanomaterials in Nanoelectronics. Business Communications Company, 2004.

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Manasreh, Omar. Introduction to Nanomaterials and Devices. Wiley & Sons, Incorporated, John, 2011.

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Manasreh, Omar. Introduction to Nanomaterials and Devices. Wiley & Sons, Incorporated, John, 2011.

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Manasreh, Omar. Introduction to Nanomaterials and Devices. Wiley & Sons, Incorporated, John, 2011.

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Manasreh, Omar. Introduction to Nanomaterials and Devices. Wiley & Sons, Limited, John, 2011.

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Book chapters on the topic "Nanomaterials- Semiconductors"

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Mathews, Manoj, Ammathnadu S. Achalkumar, and Quan Li. "Self-assembled 1D Semiconductors: Liquid Crystalline Columnar Phase." In Anisotropic Nanomaterials, 241–87. Cham: Springer International Publishing, 2015. http://dx.doi.org/10.1007/978-3-319-18293-3_7.

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Yang, Jun, and Hui Liu. "Nanocomposites of Gold and Semiconductors." In Metal-Based Composite Nanomaterials, 31–91. Cham: Springer International Publishing, 2014. http://dx.doi.org/10.1007/978-3-319-12220-5_3.

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Aravind, Arun, and M. K. Jayaraj. "Zno-Based Dilute Magnetic Semiconductors." In Materials Horizons: From Nature to Nanomaterials, 233–69. Singapore: Springer Singapore, 2020. http://dx.doi.org/10.1007/978-981-15-3314-3_8.

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Atanacio, A. J., Tad Bak, Dewei Chu, Mihail Ionescu, and Janusz Nowotny. "Segregation-Induced Low-Dimensional Surface Structures in Oxide Semiconductors." In Handbook of Nanomaterials Properties, 891–910. Berlin, Heidelberg: Springer Berlin Heidelberg, 2014. http://dx.doi.org/10.1007/978-3-642-31107-9_4.

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Zhang, Xiandi, Chui-Shan Tsang, and Lawrence Yoon Suk Lee. "Nanostructured Semiconductors for Photocatalytic CO2 Reduction." In Handbook of Nanomaterials and Nanocomposites for Energy and Environmental Applications, 2839–74. Cham: Springer International Publishing, 2021. http://dx.doi.org/10.1007/978-3-030-36268-3_103.

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Zhang, Xiandi, Chui-Shan Tsang, and Lawrence Yoon Suk Lee. "Nanostructured Semiconductors for Photocatalytic CO2 Reduction." In Handbook of Nanomaterials and Nanocomposites for Energy and Environmental Applications, 1–36. Cham: Springer International Publishing, 2020. http://dx.doi.org/10.1007/978-3-030-11155-7_103-1.

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Setia, Rupali, Harshita Chawla, and Seema Garg. "Enhancement in Degradation of Antibiotics Using Photocatalytic Semiconductors under Visible Light Irradiation." In Nanomaterials for Water Treatment and Remediation, 69–92. Boca Raton: CRC Press, 2021. http://dx.doi.org/10.1201/9781003118749-2.

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Nakayama, Yasuo, and Hisao Ishii. "Exploration into the Valence Band Structures of Organic Semiconductors by Angle-Resolved Photoelectron Spectroscopy." In Surface Science Tools for Nanomaterials Characterization, 367–404. Berlin, Heidelberg: Springer Berlin Heidelberg, 2015. http://dx.doi.org/10.1007/978-3-662-44551-8_10.

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Azarov, Alexander, Anders Hallén, and Henry H. Radamson. "Electrical Characterization of Semiconductors: I–V, C–V and Hall Measurements." In Analytical Methods and Instruments for Micro- and Nanomaterials, 197–240. Cham: Springer International Publishing, 2023. http://dx.doi.org/10.1007/978-3-031-26434-4_7.

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Shijeesh, M. R., M. Jasna, and M. K. Jayaraj. "Metal-Oxide Transistors and Calculation of the Trap Density of States in the Band Gap of Semiconductors." In Materials Horizons: From Nature to Nanomaterials, 303–18. Singapore: Springer Singapore, 2020. http://dx.doi.org/10.1007/978-981-15-3314-3_10.

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Conference papers on the topic "Nanomaterials- Semiconductors"

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Górska, M., L. Kilanski, A. Podgórni, W. Dobrowolski, R. Szymczak, J. R. Anderson, I. V. Fedorchenko, S. F. Marenkin, V. E. Slynko, and E. I. Slynko. "Magnetic properties of clusters in IV-VI and II-IV-V2diluted magnetic semiconductors." In International Symposium on Clusters and Nanomaterials, edited by Puru Jena and Anil K. Kandalam. SPIE, 2016. http://dx.doi.org/10.1117/12.2234914.

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Yong, Chaw Keong, Andrew J. Musser, Jenny Clark, John E. Anthony, David Beljonne, Richard H. Friend, and Henning Sirringhaus. "Direct observation of entangled multiexciton states in organic semiconductors (Conference Presentation)." In Physical Chemistry of Interfaces and Nanomaterials XV, edited by Artem A. Bakulin, Natalie Banerji, and Robert Lovrincic. SPIE, 2016. http://dx.doi.org/10.1117/12.2238499.

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Migliorato, M. A., J. Pal, R. Garg, G. Tse, H. Y. S. Al-Zahrani, U. Monteverde, S. Tomić, et al. "A review of non linear piezoelectricity in semiconductors." In ELECTRONIC, PHOTONIC, PLASMONIC, PHONONIC AND MAGNETIC PROPERTIES OF NANOMATERIALS. AIP Publishing LLC, 2014. http://dx.doi.org/10.1063/1.4870192.

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Hill, Eric. "Synthesis of Semiconductors Confined in Nanoscopic Colloidal Templates toward Heterostructured Nanomaterials." In Internet NanoGe Conference on Nanocrystals. València: Fundació Scito, 2021. http://dx.doi.org/10.29363/nanoge.incnc.2021.008.

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Beck, Sebastian, Sabina Hillebrandt, and Annemarie Pucci. "IR spectroscopic investigation of charge transfer at interfaces of organic semiconductors (Conference Presentation)." In Physical Chemistry of Interfaces and Nanomaterials XV, edited by Artem A. Bakulin, Natalie Banerji, and Robert Lovrincic. SPIE, 2016. http://dx.doi.org/10.1117/12.2238493.

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Izquierdo, Ricardo. "Combination of Nanomaterials and Organic Semiconductors for Electronic and Optoelectronic Device Fabrication." In International Conference of Theoretical and Applied Nanoscience and Nanotechnology. Avestia Publishing, 2017. http://dx.doi.org/10.11159/tann17.3.

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Gan'shina, E., G. Zykov, L. Golik, Z. Kun'kova, A. Rukovishnikov, M. Temiryazeva, Y. Markin, and V. Lesnikov. "Spectroscopic and microscopic investigations of InFeSb diluted magnetic semiconductors prepared by laser ablation." In 2017 IEEE 7th International Conference "Nanomaterials: Application & Properties" (NAP). IEEE, 2017. http://dx.doi.org/10.1109/nap.2017.8190382.

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Bondarenko, I. N., V. A. Nikolaenko, and A. V. Polishchuk. "The cavity with the Tunnel Diodes and Corbino-Electrodes for Analyze Dielectrics and Semiconductors." In 2019 IEEE 9th International Conference Nanomaterials: Applications & Properties (NAP). IEEE, 2019. http://dx.doi.org/10.1109/nap47236.2019.219085.

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Hepplestone, S. P., G. P. Srivastava, M. R. Singh, and R. H. Lipson. "Atomic Theory Of Phononic Gaps In Nano-patterned Semiconductors." In TRANSPORT AND OPTICAL PROPERTIES OF NANOMATERIALS: Proceedings of the International Conference—ICTOPON-2009. AIP, 2009. http://dx.doi.org/10.1063/1.3183421.

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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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Reports on the topic "Nanomaterials- Semiconductors"

1

Forde, Aaron. Non -Equilibrium and Novel Photo-Physics in Semiconductor Nanomaterials and Bio-Organic Systems. Office of Scientific and Technical Information (OSTI), April 2023. http://dx.doi.org/10.2172/1972085.

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Armstrong, Neal R. Asymmetric Semiconductor Nanorod/Oxide Nanoparticle Hybrid Materials: Model Nanomaterials for Light-Activated Formation of Fuels from Sunlight. Formal Progress Report -- Award DE-FG02-05ER15753. Office of Scientific and Technical Information (OSTI), June 2017. http://dx.doi.org/10.2172/1365549.

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