Letteratura scientifica selezionata sul tema "Photocatalysis"

Cita una fonte nei formati APA, MLA, Chicago, Harvard e in molti altri stili

Scegli il tipo di fonte:

Consulta la lista di attuali articoli, libri, tesi, atti di convegni e altre fonti scientifiche attinenti al tema "Photocatalysis".

Accanto a ogni fonte nell'elenco di riferimenti c'è un pulsante "Aggiungi alla bibliografia". Premilo e genereremo automaticamente la citazione bibliografica dell'opera scelta nello stile citazionale di cui hai bisogno: APA, MLA, Harvard, Chicago, Vancouver ecc.

Puoi anche scaricare il testo completo della pubblicazione scientifica nel formato .pdf e leggere online l'abstract (il sommario) dell'opera se è presente nei metadati.

Articoli di riviste sul tema "Photocatalysis"

1

Wang, Shifa, Peilin Mo, Dengfeng Li e Asad Syed. "Intelligent Algorithms Enable Photocatalyst Design and Performance Prediction". Catalysts 14, n. 4 (22 marzo 2024): 217. http://dx.doi.org/10.3390/catal14040217.

Testo completo
Abstract (sommario):
Photocatalysts have made great contributions to the degradation of pollutants to achieve environmental purification. The traditional method of developing new photocatalysts is to design and perform a large number of experiments to continuously try to obtain efficient photocatalysts that can degrade pollutants, which is time-consuming, costly, and does not necessarily achieve the best performance of the photocatalyst. The rapid development of photocatalysis has been accelerated by the rapid development of artificial intelligence. Intelligent algorithms can be utilized to design photocatalysts and predict photocatalytic performance, resulting in a reduction in development time and the cost of new catalysts. In this paper, the intelligent algorithms for photocatalyst design and photocatalytic performance prediction are reviewed, especially the artificial neural network model and the model optimized by an intelligent algorithm. A detailed discussion is given on the advantages and disadvantages of the neural network model, as well as its application in photocatalysis optimized by intelligent algorithms. The use of intelligent algorithms in photocatalysis is challenging and long term due to the lack of suitable neural network models for predicting the photocatalytic performance of photocatalysts. The prediction of photocatalytic performance of photocatalysts can be aided by the combination of various intelligent optimization algorithms and neural network models, but it is only useful in the early stages. Intelligent algorithms can be used to design photocatalysts and predict their photocatalytic performance, which is a promising technology.
Gli stili APA, Harvard, Vancouver, ISO e altri
2

Prakash, Jai. "Mechanistic Insights into Graphene Oxide Driven Photocatalysis as Co-Catalyst and Sole Catalyst in Degradation of Organic Dye Pollutants". Photochem 2, n. 3 (17 agosto 2022): 651–71. http://dx.doi.org/10.3390/photochem2030043.

Testo completo
Abstract (sommario):
Photocatalysis is a promising route to utilize sunlight, which has been potentially used to solve energy as well as environmental problems with an emphasis on fundamental understanding and technological applications in society. Semiconductors are excellent photocatalysts but often show less efficient activities due to the fast recombination of photogenerated charge carriers and very slow kinetics of surface photochemical reactions. However, recent advancements show promising strategies to improve their photocatalytic activities, including surface modifications using suitable co-catalysts and the development of novel efficient photocatalysts. Graphene oxide (GO) is one of such nanomaterials which shows multifarious roles in photocatalysis with a great potential to act as an independent solar-driven sole photocatalyst. In this minireview, the photochemistry of GO has been discussed in view of its multifarious roles/mechanisms in improving the photocatalytic activity of metal oxide semiconductors, plasmonic nanomaterials, and also their nanocomposites. In addition, recent advancements and applications of such GO-based photocatalysts in photocatalytic degradation of organic dye pollutants, including engineering of GO as the sole photocatalyst, have been discussed. Furthermore, the challenges and future prospects for the development of GO-based photocatalysts are discussed.
Gli stili APA, Harvard, Vancouver, ISO e altri
3

Yu, Haidong, Haibing Jiang, Shuji Zhang, Xin Feng, Song Yin e Wenzhi Zhao. "Review of Two-Dimensional MXenes (Ti3C2Tx) Materials in Photocatalytic Applications". Processes 11, n. 5 (6 maggio 2023): 1413. http://dx.doi.org/10.3390/pr11051413.

Testo completo
Abstract (sommario):
MXenes (Ti3C2Tx) have gotten a lot of interest since their discovery in 2011 because of their distinctive two-dimensional layered structure, high conductivity, and rich surface functional groups. According to the findings, MXenes (Ti3C2Tx) may block photogenerated electron-hole recombination in the photocatalytic system and offer many activation reaction sites, enhancing the photocatalytic performance and demonstrating tremendous promise in the field of photocatalysis. This review discusses current Ti3C2Tx-based photocatalyst preparation techniques, such as ultrasonic mixing, electrostatic self-assembly, hydrothermal preparation, and calcination techniques. We also summarised the advancements in photocatalytic CO2 reduction, photocatalytic nitrogen fixation, photocatalytic hydrogen evolution, and Ti3C2Tx-based photocatalysts in photocatalytic degradation of pollutants. Lastly, the challenges and prospects of Ti3C2Tx in photocatalysis are discussed based on the practical application of Ti3C2Tx.
Gli stili APA, Harvard, Vancouver, ISO e altri
4

Li, Xue, Ulla Simon, Maged F. Bekheet e Aleksander Gurlo. "Mineral-Supported Photocatalysts: A Review of Materials, Mechanisms and Environmental Applications". Energies 15, n. 15 (2 agosto 2022): 5607. http://dx.doi.org/10.3390/en15155607.

Testo completo
Abstract (sommario):
Although they are of significant importance for environmental applications, the industrialization of photocatalytic techniques still faces many difficulties, and the most urgent concern is cost control. Natural minerals possess abundant chemical inertia and cost-efficiency, which is suitable for hybridizing with various effective photocatalysts. The use of natural minerals in photocatalytic systems can not only significantly decrease the pure photocatalyst dosage but can also produce a favorable synergistic effect between photocatalyst and mineral substrate. This review article discusses the current progress regarding the use of various mineral classes in photocatalytic applications. Owing to their unique structures, large surface area, and negatively charged surface, silicate minerals could enhance the adsorption capacity, reduce particle aggregation, and promote photogenerated electron-hole pair separation for hybrid photocatalysts. Moreover, controlling the morphology and structure properties of these materials could have a great influence on their light-harvesting ability and photocatalytic activity. Composed of silica and alumina or magnesia, some silicate minerals possess unique orderly organized porous or layered structures, which are proper templates to modify the photocatalyst framework. The non-silicate minerals (referred to carbonate and carbon-based minerals, sulfate, and sulfide minerals and other special minerals) can function not only as catalyst supports but also as photocatalysts after special modification due to their unique chemical formula and impurities. The dye-sensitized minerals, as another natural mineral application in photocatalysis, are proved to be superior photocatalysts for hydrogen evolution and wastewater treatment. This work aims to provide a complete research overview of the mineral-supported photocatalysts and summarizes the common synergistic effects between different mineral substrates and photocatalysts as well as to inspire more possibilities for natural mineral application in photocatalysis.
Gli stili APA, Harvard, Vancouver, ISO e altri
5

Gusarov, Sergey. "Advances in Computational Methods for Modeling Photocatalytic Reactions: A Review of Recent Developments". Materials 17, n. 9 (30 aprile 2024): 2119. http://dx.doi.org/10.3390/ma17092119.

Testo completo
Abstract (sommario):
Photocatalysis is a fascinating process in which a photocatalyst plays a pivotal role in driving a chemical reaction when exposed to light. Its capacity to harness light energy triggers a cascade of reactions that lead to the formation of intermediate compounds, culminating in the desired final product(s). The essence of this process is the interaction between the photocatalyst’s excited state and its specific interactions with reactants, resulting in the creation of intermediates. The process’s appeal is further enhanced by its cyclic nature—the photocatalyst is rejuvenated after each cycle, ensuring ongoing and sustainable catalytic action. Nevertheless, comprehending the photocatalytic process through the modeling of photoactive materials and molecular devices demands advanced computational techniques founded on effective quantum chemistry methods, multiscale modeling, and machine learning. This review analyzes contemporary theoretical methods, spanning a range of lengths and accuracy scales, and assesses the strengths and limitations of these methods. It also explores the future challenges in modeling complex nano-photocatalysts, underscoring the necessity of integrating various methods hierarchically to optimize resource distribution across different scales. Additionally, the discussion includes the role of excited state chemistry, a crucial element in understanding photocatalysis.
Gli stili APA, Harvard, Vancouver, ISO e altri
6

Cheng, Yan, Chenxi Li, Shindume Lomboleni Hamukwaya, Guangdong Huang e Zengying Zhao. "Synthesis of Composite Titanate Photocatalyst via Molten Salt Processing and Its Enhanced Photocatalytic Properties". Nanomaterials 13, n. 22 (14 novembre 2023): 2944. http://dx.doi.org/10.3390/nano13222944.

Testo completo
Abstract (sommario):
Photocatalysis plays a pivotal role in environmental remediation and energy production and improving the efficiency of photocatalysts, yet enhancing its efficiency remains a challenge. Titanate has been claimed to be a very promising material amongst various photocatalysts in recent years. In this work, a novel composite photocatalyst of sodium titanate and potassium titanate was synthesized via a simple hydrothermal and molten salt calcination method. Low melting point nitrate was added in the calcination process, which helps reduce the calcination temperature. The as-prepared composite sample showed excellent photocatalytic performance compared with commercial P25 in the visible light range. According to the characterization of XRD, SEM, TEM, BET, UV–Vis, and photocatalytic property testing, the composite’s photocatalytic performance results are due to the dual optimization brought about by the layered structure and composite of titanium salts forming a heterojunction. We believe that the composite has significant application potential for the use of titanate in the field of photocatalysis. Notably, this study employed well-documented synthesis methods and adhered to established protocols for experimental procedures.
Gli stili APA, Harvard, Vancouver, ISO e altri
7

Kudo, Akihiko. "Photocatalysis and solar hydrogen production". Pure and Applied Chemistry 79, n. 11 (1 gennaio 2007): 1917–27. http://dx.doi.org/10.1351/pac200779111917.

Testo completo
Abstract (sommario):
Photocatalytic water splitting is a challenging reaction because it is an ultimate solution to energy and environmental issues. Recently, many new powdered photocatalysts for water splitting have been developed. For example, a NiO (0.2 wt %)/NaTaO3:La (2 %) photocatalyst with a 4.1-eV band gap showed high activity for water splitting into H2 and O2 with an apparent quantum yield of 56 % at 270 nm. Overall water splitting under visible light irradiation has been achieved by construction of a Z-scheme photocatalysis system employing visible-light-driven photocatalysts, Ru/SrTiO3:Rh and BiVO4 for H2 and O2 evolution, and an Fe3+/Fe2+ redox couple as an electron relay. Moreover, highly efficient sulfide photocatalysts for solar hydrogen production in the presence of electron donors were developed by making solid solutions of ZnS with AgInS2 and CuInS2 of narrow band gap semiconductors. Thus, the database of powdered photocatalysts for water splitting has become plentiful.
Gli stili APA, Harvard, Vancouver, ISO e altri
8

Ren, Yu, Yuze Dong, Yaqing Feng e Jialiang Xu. "Compositing Two-Dimensional Materials with TiO2 for Photocatalysis". Catalysts 8, n. 12 (28 novembre 2018): 590. http://dx.doi.org/10.3390/catal8120590.

Testo completo
Abstract (sommario):
Energy shortage and environmental pollution problems boost in recent years. Photocatalytic technology is one of the most effective ways to produce clean energy—hydrogen and degrade pollutants under moderate conditions and thus attracts considerable attentions. TiO2 is considered one of the best photocatalysts because of its well-behaved photo-corrosion resistance and catalytic activity. However, the traditional TiO2 photocatalyst suffers from limitations of ineffective use of sunlight and rapid carrier recombination rate, which severely suppress its applications in photocatalysis. Surface modification and hybridization of TiO2 has been developed as an effective method to improve its photocatalysis activity. Due to superior physical and chemical properties such as high surface area, suitable bandgap, structural stability and high charge mobility, two-dimensional (2D) material is an ideal modifier composited with TiO2 to achieve enhanced photocatalysis process. In this review, we summarized the preparation methods of 2D material/TiO2 hybrid and drilled down into the role of 2D materials in photocatalysis activities.
Gli stili APA, Harvard, Vancouver, ISO e altri
9

Dutta, Vishal, Ankush Chauhan, Ritesh Verma, C. Gopalkrishnan e Van-Huy Nguyen. "Recent trends in Bi-based nanomaterials: challenges, fabrication, enhancement techniques, and environmental applications". Beilstein Journal of Nanotechnology 13 (11 novembre 2022): 1316–36. http://dx.doi.org/10.3762/bjnano.13.109.

Testo completo
Abstract (sommario):
One of the most enticing approaches to environmental restoration and energy conversion is photocatalysis powered by solar light. Traditional photocatalysts have limited practical uses due to inadequate light absorption, charge separation, and unknown reaction mechanisms. Discovering new visible-light photocatalysts and investigating their modification is crucial in photocatalysis. Bi-based photocatalytic nanomaterials have gotten much interest as they exhibit distinctive geometric shapes, flexible electronic structures, and good photocatalytic performance under visible light. They can be employed as stand-alone photocatalysts for pollution control and energy production, but they do not have optimum efficacy. As a result, their photocatalytic effectiveness has been significantly improved in the recent decades. Numerous newly created concepts and methodologies have brought significant progress in defining the fundamental features of photocatalysts, upgrading the photocatalytic ability, and understanding essential reactions of the photocatalytic process. This paper provides insights into the characteristics of Bi-based photocatalysts, making them a promising future nanomaterial for environmental remediation. The current review discusses the fabrication techniques and enhancement in Bi-based semiconductor photocatalysts. Various environmental applications, such as H2 generation and elimination of water pollutants, are also discussed in terms of semiconductor photocatalysis. Future developments will be guided by the uses, issues, and possibilities of Bi-based photocatalysts.
Gli stili APA, Harvard, Vancouver, ISO e altri
10

Shen, Liqiang, Tingting Ye, Yehui Chen, Bei Chu, Hui Chen, Jinxing Hu e Yan Yu. "Facile Synthesis of a Novel AgIO3/CTF Heterojunction and Its Adsorption–Photocatalytic Performance with Organic Pollutants". Toxics 12, n. 2 (6 febbraio 2024): 133. http://dx.doi.org/10.3390/toxics12020133.

Testo completo
Abstract (sommario):
With the development of modern industry, the issue of water pollution has garnered increasing attention. Photocatalysis, as a novel green environmental technology that is resource-efficient, environmentally friendly, and highly promising, has found extensive applications in the field of organic pollutant treatment. However, common semiconductor materials exhibit either a relatively low photocatalytic efficiency in the visible light range or an inefficient separation of photogenerated charges, resulting in their limited ability to harness solar energy effectively. Consequently, the development of new photocatalysts has become a pivotal focus in current photocatalysis research to enhance solar energy utilization. This research provides a brief explanation of the photocatalytic mechanism of the AgIO3/CTF heterojunction photocatalyst. Due to the localized surface plasmon resonance (LSPR) effect, the Ag nanoparticles demonstrate significant absorption in the visible light region, playing a crucial role in the highly efficient photocatalytic reduction of organic pollutants.
Gli stili APA, Harvard, Vancouver, ISO e altri

Tesi sul tema "Photocatalysis"

1

He, Jijiang. "Preparation and photocatalysis of graphite carbon nitride based photocatalysts". Thesis, Curtin University, 2015. http://hdl.handle.net/20.500.11937/521.

Testo completo
Abstract (sommario):
The connection between ritual and the interior is interrogated through a theoretical framework integrating Van Gennep’s Rites of Passage Theory and Turner’s Theory of Liminality. A multi-faceted methodological framework is developed from the interrogation of the disciplinary edges of multiple methodologies, addressing the experiential, cultural and subjective dimensions of ritual. This new way of exploring the interior demonstrates how knowledge can be acquired from the body’s immersion in unfolding ritual situations, revealing elements of ritual and interior in relation to one another and the generation of new theories on the interior.
Gli stili APA, Harvard, Vancouver, ISO e altri
2

Zhou, Ruixin. "SEMICONDUCTOR PHOTOCATALYSIS: MECHANISMS, PHOTOCATALYTIC PERFORMANCES AND LIFETIME OF REDOX CARRIERS". UKnowledge, 2017. http://uknowledge.uky.edu/chemistry_etds/85.

Testo completo
Abstract (sommario):
Photocatalytic reactions mediated by semiconductors such as ZnS, TiO2, ZnO, etc. can harvest solar energy into chemical bonds, a process with important prebiotic and environmental chemistry applications. The recycling of CO2 into organic molecules (e.g., formate, methane, and methanol) facilitated by irradiated semiconductors such as colloidal ZnS nanoparticles has been demonstrated. ZnS can also drive prebiotic reactions from the reductive tricarboxylic acid (rTCA) cycle such as the reduction of fumarate to succinate. However, the mechanism of photoreduction by ZnS of the previous reaction has not been understood. Thus, this thesis reports the mechanisms for heterogeneous photocatalytic reductions on ZnS for two model reactions in water with sulfide hole scavenger. First the reduction of CO2 is carried out under variable wavelength of irradiation and proposed to proceed thorough five steps resulting in the exclusive formation of formate. Second the reduction of the double bond of fumaric acid to succinic acid is reported in detail and compared to the previous conversion of CO2 to formic acid. Both reactions are carried out under variable wavelength of irradiation and proposed to proceed thorough one electron transfer at a time. In addition, a new method to measure the bandgap of colloidal ZnS suspended in water is established. Furthermore, the time scales of electron transfer and oxidizing hole loss during irradiation of ZnS for both reactions are reported and interpreted in terms of the Butler-Volmer equation. The sunlight promoted production of succinate introduced above, provides a connection of this prebiotic chemistry work to explore if central metabolites of the rTCA cycle can catalyze the synthesis of clay minerals. Clay minerals are strong adsorbents that can retain water and polar organic molecules, which facilitate the polymerization of biomolecules and conversion of fatty acid micelles into vesicles under prebiotic conditions relevant to the early Earth. While typical clay formation requires high temperatures and pressures, this process is hypothesized herein to be accelerated by central metabolites. A series of synthesis are designed to last only 20 hours to study the crystallization of sauconite, an Al- and Zn-rich model clay, at low temperature and ambient pressure in the presence of succinate as a catalyst. Succinate promotes the formation of the trioctahedral 2:1 layer silicate at ≥ 75 °C, 6.5 ≤ pH ≤ 14, [succinate] ≥ 0.01 M. Cryogenic and conventional transmission electron microscopies, X-ray diffraction, diffuse reflectance Fourier transformed infrared spectroscopy, and measurements of total surface area and cation exchange capacity are used to study the time evolution during the synthesis of sauconite. While the studies with ZnS presented above advanced the fundamental understanding of photocatalysis with single semiconductors, the environmental applications of this material appear limited. A common limitation to photocatalysis with single semiconductors is the rapid recombination of photogenerated electron-hole pairs, which reduces significantly the efficiency of the process that in the case of ZnS also suffers from photocorrosion in the presence of air. In order to overcome the fast charge recombination and the limited visible-light absorption of semiconductor photocatalysts, an effective strategy is developed in this work by combining two semiconductors into a nanocomposite. This nanocomposite is solvothermally synthesized creating octahedral cuprous oxide covered with titanium dioxide nanoparticles (Cu2O/TiO2). The nanocomposite exhibits unique surface modifications that provide a heterojunction with a direct Z-scheme for optimal CO2 reduction. The band structure of the nanocomposite is characterized by diffused reflectance UV-visible spectroscopy, X-ray photoelectron spectroscopy (XPS) and ultraviolet photoelectron spectroscopy. The photoreduction of CO2(g) to CO(g) on the nanocomposite is investigated in the presence water vapor as the hole scavenger that generates the quantifiable hydroxyl radical (). The quantum efficiency of CO production under irradiation at λ ≥ 305 nm with the nanocomposite is 2-times larger than for pure Cu2O. The detection of and XPS analysis contrasting the stability of Cu2O/TiO2 vs Cu2O during irradiation prove that TiO2 prevents the photocorrosion of Cu2O. Overall, the studies of photocatalytic reductions on single component semiconductors reveal new knowledge needed for developing future photocatalytic application for fuel production, wastewater treatment, reducing air pollution, and driving important prebiotic chemistry reactions. Furthermore, the design of a photocatalyst operating under a Z-scheme mechanism provides a new proof of concept for the design of systems that mimic photosynthesis. Finally, this work also demonstrates how molecules obtained by mineral mediated photochemistry can catalyze clay formation; highlighting the important role that photochemistry may have played for the origin of life on the early Earth and other rocky planets.
Gli stili APA, Harvard, Vancouver, ISO e altri
3

Plumejeau, Sandrine. "Croissance de TiO₂ en surface de fibres de cellulose pour l'élaboration de filtres photocatalytiques". Thesis, Montpellier, 2016. http://www.theses.fr/2016MONTT230/document.

Testo completo
Abstract (sommario):
La dépollution est aujourd’hui un enjeu majeur pour la protection de l’environnement et un développement durable. Les technologies membranaires et les procédés d’oxydation avancée jouent un rôle de plus en plus important dans le traitement de l'eau que ce soit pour la production d’eau potable que pour le traitement des eaux usées urbaines ou industrielles. La photocatalyse hétérogène est un procédé d’oxydation avancée permettant la génération des espèces très oxydantes comme les radicaux OH•, en présence d’eau et de dioxygène, lors de l’irradiation de certains solides semi-conducteurs au premier rang desquels on retrouve le dioxyde de titane. L’objectif final visé dans cette thèse est le développement de filtres photocatalytiques performants mis en œuvre dans des procédés hybrides couplant séparation et photodégradation. Le mode d’élaboration envisagé pour ces filtres photocatalytiques est basé sur une voie de synthèse en rupture utilisant un polymère biosourcé, la cellulose, à la fois comme réactif (source d’oxygène) et support mécanique pour la croissance de nanoparticules de TiO2 à partir de tétrachlorure de titane. La première partie de la thèse est dédiée à une revue bibliographique qui porte principalement sur les procédés membranaires et hybrides, le dioxyde de titane et ses propriétés photocatalytiques et sur les propriétés chimiques, structurales et microstructurales et l’évolution thermique de la cellulose. Après un descriptif des matériels et méthodes mis en œuvre dans l’étude expérimentale sont d’abord présentés et discutés les résultats obtenus sur la préparation et la caractérisation de poudres purement minérales, à base de TiO2, et de poudres composites TiO2-carbone. L’effet du dopage du TiO2 par différents métaux de transition afin d’améliorer ses propriétés fonctionnelles est ensuite examiné. Une simplification du procédé de synthèse consistant à éliminer tout usage de solvant est exposée dans le chapitre suivant. S’appuyant sur le savoir-faire précédemment acquis en matière de synthèse et sur les performances photocatalytiques préalablement mesurées, le dernier chapitre est consacré aux travaux préliminaires menés sur la préparation de filtres photocatalytiques et sur l’évaluation leurs performances fonctionnelles
The pollution is definitely a major issue for environmental protection and sustainable development. Membrane technologies and advanced oxidation processes play more and more a key-role in the treatment of water both for the production of drinking water and for the treatment of municipal and industrial wastewaters. Heterogeneous photocatalysis is an advanced oxidation process for generating highly oxidizing species such as OH• in the presence of water and dioxygen, under irradiation of some semiconducting solids like titania (TiO2). The targeted objective for this PhD work is the development of efficient photocatalytic filters to be implemented in hybrid processes coupling separation and photodegradation. The innovative route investigated for preparing such photocatalytic filters is based on the use of a bio-based polymer, i.e. the cellulose, both as reactant (oxygen source) and mechanical support for the growth of titania nanoparticles from titanium tetrachloride. The first part of the thesis is dedicated to a literature review mainly focused on membrane and hybrid processes, on titanium dioxide and its photocatalytic properties and on the chemical, structural, microstructural and thermal behaviour of cellulose. After a description of the experimental procedures, the second part of this manuscript is first dedicated to the presentation and the discussion of the experimental results on the preparation and characterization of pure titania powders and of TiO2-carbon composite powders. The effect of titania doping by different transition metals in order to improve its functional properties is then examined. Simplification of the synthesis process by removing any is described in the next chapter. From the previously developed know-how on synthesis and photocatalytic performance, the last chapter is devoted to preliminary work on the preparation of photocatalytic filters and on the assessment of their functional properties
Gli stili APA, Harvard, Vancouver, ISO e altri
4

Guo, Muyao, e 郭牧遥. "Metal oxide photocatalysis". Thesis, The University of Hong Kong (Pokfulam, Hong Kong), 2013. http://hub.hku.hk/bib/B50434457.

Testo completo
Abstract (sommario):
Photocatalysis has been attracting much research interest because of its wide applications in renewable energy and environmental remediation. Among the photocatalysts, metal oxide semiconductors are the best choice due to distinctive properties, durability and cost effectiveness. However, the mechanisms of photocatalysis are still not entirely clear and the photocatalytic activity of the metal oxide materials needs to be improved. Therefore, this thesis concentrates on the study of the photocatalytic mechanism and the factors affecting the photocatalytic activity. The photocatalysis of different commercial metal oxide nanoparticles has been studied. Different photocatalytic experiments have been designed to find out the mechanisms of photocatalysis. It is found that the dominant mechanism of photocatalysis is direct charge transfer between metal oxide and organic compounds. Reactive oxygen species, such as hydroxyl radicals also play a minor role in the photocatalysis. ZnO tetrapods were synthesized by evaporating Zn powder in the flow of Ar gas at high temperature in this study. They exhibit excellent photocatalytic activity. By the comparison between ZnO tetrapods and different ZnO nanoparticles, it is found that the photocatalytic activity of the metal oxide is strongly affected by the native defects, especially by the nonradiative defects. 1D TiO2 nanotubes and ZnO nanorods were synthesized by anodization and hydrothermal growth respectively. ZnO nanorods with alumina and titania shell were prepared by solution-based methods. These structures are interesting as supported catalysts, which is important for practical applications, since it enables simple removal of photocatalyst from treated water. The core shell structures are expected to improve the stability of ZnO. The results also imply that the photocatalytic avtivity of materials is affected by the native defects. Two different solution based methods hydrothermal growth and electrodeposition to grow CuxO layer were used. The hydrothermal grown CuxO exhibit excellent photocatalytic activity and good photocorrosion resistance. It was also found that the photocatalytic activity of the CuxO prepared by hydrothermal methods can be recovered by simple immersion of the sample into the precursor solution.
published_or_final_version
Physics
Master
Master of Philosophy
Gli stili APA, Harvard, Vancouver, ISO e altri
5

Jackson, S. A. "Intermediates in photocatalysis". Thesis, University of Nottingham, 1988. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.384288.

Testo completo
Gli stili APA, Harvard, Vancouver, ISO e altri
6

Qiao, Yu. "Preparation, Characterization, and Evaluation of Photocatalytic Properties of a Novel NaNbO3/Bi2WO6 Heterostructure Photocatalyst for Water Treatment". Thesis, Université d'Ottawa / University of Ottawa, 2018. http://hdl.handle.net/10393/38080.

Testo completo
Abstract (sommario):
Semiconductor-based heterogeneous photocatalysis, as one of the advanced oxidation processes that makes use of semiconductors and inexhaustible solar light, has recently been extensively studied and applied to water decontamination. However, due to low light absorption efficiencies and severe electron-hole recombination, modifications on semiconductor structures are required in order to enhance their photocatalytic performance. Heterogeneous photocatalyst composites, taking advantage of the improved light absorption efficiency as well as the facilitated electron-hole separation at the interface between different semiconductors, have been proven to be a promising strategy. In this study, novel NaNbO3/Bi2WO6 photocatalyst composites with a type-II heterogeneous alignment were successfully prepared via a facile wet impregnation method. The as-prepared photocatalysts were characterized by powder X-ray diffraction (XRD), scanning electron microscopy (SEM), high-resolution transmission electron microscopy (HRTEM), X-ray photoelectron spectroscopy (XPS), diffuse reflectance UV-Vis spectroscopy (DRS), photocurrent (PC) and electrochemical impedance spectroscopy (EIS) analyses. The 30 wt% NaNbO3/Bi2WO6 composite exhibited the best performance for degrading an RhB (rhodamine B) aqueous solution under visible light irradiation (λ > 410 nm), which was ca. 40 times and ca. 2.5 times that of the pristine NaNbO3 and Bi2WO6, respectively. The improved photocatalytic activity may be attributed to the enhanced electron-hole separation efficiency in Bi2WO6 with the assistance of NaNbO_3, as well as the dye-sensitization effect of RhB itself. Radical quenching experiments revealed that h+ played the predominant role, and O2•- functioned as well to some degree. The produced intermediates during the reaction and RhB degradation pathway were speculated and investigated as well. The excellent stability and reusability were verified by repetitively running for five times. Based on experimental results, a plausible functioning mechanism was proposed. Effects of several operation parameters on the catalyst performance including initial RhB concentration, catalyst dosage, reaction temperature and initial pH were also discussed. This study provides solid evidence for NaNbO3 to be a promising candidate for photocatalysis and gives out a novel photocatalytic mechanism of Bi2WO6-based type-II heterostructures.
Gli stili APA, Harvard, Vancouver, ISO e altri
7

Yatmaz, Huseyin Cengiz. "Photocatalysis of organic effluents". Thesis, University of Newcastle Upon Tyne, 1993. http://hdl.handle.net/10443/271.

Testo completo
Abstract (sommario):
Heterogeneous photocatalytic oxidation is a relatively new technology for the destruction of toxic organic substances in water and so far has concentrated on reaction mechanisms and kinetics, but the engineering side was hardly touched. In this study a detailed investigation for suitable reactor design has been carried out using three different reactor types. An annular photoreactor was used with two different lamps with different intensities; low pressure and medium pressure mercury lamps. Two types of Ti02 powder catalysts Degussa P-25 and Tioxide PCi were used as slurry solutions and Degussa P-25 was found more photocatalytically active than the other. Two main organic reactants salicylic acid and 4-chlorophenol were studied to assess the light intensity effect. Although better reaction rates were achieved with the higher intensity medium pressure lamp, quantum yield results showed that low pressure lamp photons were utiised more effectively. The falling film reactor (FFR) was used to increase the light intensity utilisation with the stronger medium pressure lamp and using the same reactants in slurries catalysts Degussa P-25 gave superior results to those in annular reactor. Because of the thin film characteristics, FFR provided good oxygen transfer at the film/air interface. A commercial supported catalyst system as a fibre glass gauze was also used inside the reactor and was found as effective as slurry systems. In order to improve the thin film characteristics and combine these with an immobiised catalyst, a spinning disc reactor (SDR) with catalyst coated borosilicate disc was used to degrade aqueous solutions of 4- chlorophenol and salicylic acid. It was found that the efficiency of the photocatalyst process was dependent upon the type of UV source used. Lamps supplying shorter wavelength UV radiation were found to be more efficient than those whose emissions lay mainly in the near UV region. The method used to coat the disc of the SDR does not appear to meet its operational requirements.
Gli stili APA, Harvard, Vancouver, ISO e altri
8

O'Rourke, Christopher. "Photocatalysis for organic synthesis". Thesis, Queen's University Belfast, 2014. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.675420.

Testo completo
Abstract (sommario):
A wide range of commercially available self-cleaning materials/products are now available, from architectural materials, such as; glass, paint, plastics, and concrete, to water and air purification systems. These products exploit the destructive oxidative nature of SPC to purify air and water. In contrast, this thesis introduces the less well studied use of SPC to mediate the synthesis of a range of useful organic species, and aims to develop a fast screening process for monitoring such reactions to aid future developments in SPC mediated organic synthesis. It is demonstrated that NMR is a very effective way to monitor SPC mediated organic reactions. By coating the inside of an NMR tube with a sol-gel titania film, and performing SPC reactions in-situ, inside a sealed NMR tube on a 1 mL scale, the need for sample-taking and pre-treatment is negated. The small scale also allows for much faster reaction times. For example, it is shown for the SPC oxidation of toluene, that the use of this NMR/sol-gel titania method is ca. 10 times faster than the more conventional large scale (100 mL) reaction utilising a titania dispersion, whilst still providing similar product yields, thus, demonstrating a new rapid screening method for SPC mediated organic synthesis reactions. Using the new fast screening NMR tube method, the SPC C-C coupling of phenoxyacetic acid (PAA) with N-methylmaleimide (NMI) to produce adduct and cyclic products in yields up to 67% and 15% respectively after only 15 min of UVA irradiation was assessed in detail. Despite the well-known photochemical feature of NMI to form dimers efficiently, the background photochemistry and photocatalysis associated with the individual reactants are shown to be minimal due to the faster SPC kinetics for the coupling reaction. Acrylamide (ACM) was also used in the SPC C-C coupling with PAA, gaving rise to only one product, 4-phenoxybutanamide, in high yields (78%). This efficient reaction was then used to assess the robustness and reusability of the titania coated NMR tubes.
Gli stili APA, Harvard, Vancouver, ISO e altri
9

Cornu, Catherine J. G. Hoffmann Michael R. "Photocatalysis under periodic illumination". Diss., Pasadena, Calif. : California Institute of Technology, 2002. http://resolver.caltech.edu/CaltechETD:etd-05082006-143046.

Testo completo
Gli stili APA, Harvard, Vancouver, ISO e altri
10

Mercer, Sarah M. "Heterogeneous photocatalysis: Design and experimental characterization of a new photocatalytic reactor for wastewater treatment". Thesis, University of Ottawa (Canada), 2006. http://hdl.handle.net/10393/27393.

Testo completo
Abstract (sommario):
The objective of this study is to promote photocatalytic wastewater treatment by proposing a reactor design that employs a catalyst-coated, rotating, corrugated drum to increase the surface area, induce agitation and promote reactant and photon transfer to the surface. Corrugation profiles with surface areas ranging from 405 cm2 to 3650 cm2 were considered---the addition of corrugations improved the phenol degradation rate by up to 200%. Based on an analysis of rotational speed and initial pollutant concentration, the reaction was found to be limited by the kinetics at 20 ppm and 40 ppm, but limited by phenol transfer to the reaction sites at 5 ppm. Finally, Langmuir-Hinshelwood kinetics was applicable with an average phenol adsorption coefficient of 0.120 L/mg and an increasing overall reaction rate constant with surface area. Further studies are necessary for the industrial use of such a reactor design including treatment of wastewater with varying characteristics, reactor design scaling and the applicability of this design for solar-activated applications.
Gli stili APA, Harvard, Vancouver, ISO e altri

Libri sul tema "Photocatalysis"

1

Schneider, Jenny, Detlef Bahnemann, Jinhua Ye, Gianluca Li Puma e Dionysios D. Dionysiou, a cura di. Photocatalysis. Cambridge: Royal Society of Chemistry, 2016. http://dx.doi.org/10.1039/9781782622338.

Testo completo
Gli stili APA, Harvard, Vancouver, ISO e altri
2

Dionysiou, Dionysios D., Gianluca Li Puma, Jinhua Ye, Jenny Schneider e Detlef Bahnemann, a cura di. Photocatalysis. Cambridge: Royal Society of Chemistry, 2016. http://dx.doi.org/10.1039/9781782627104.

Testo completo
Gli stili APA, Harvard, Vancouver, ISO e altri
3

Bignozzi, Carlo Alberto, a cura di. Photocatalysis. Berlin, Heidelberg: Springer Berlin Heidelberg, 2011. http://dx.doi.org/10.1007/978-3-642-22294-8.

Testo completo
Gli stili APA, Harvard, Vancouver, ISO e altri
4

Zhang, Jinlong, Baozhu Tian, Lingzhi Wang, Mingyang Xing e Juying Lei. Photocatalysis. Singapore: Springer Singapore, 2018. http://dx.doi.org/10.1007/978-981-13-2113-9.

Testo completo
Gli stili APA, Harvard, Vancouver, ISO e altri
5

Bignozzi, Carlo Alberto. Photocatalysis. Berlin, Heidelberg: Springer-Verlag Berlin Heidelberg, 2011.

Cerca il testo completo
Gli stili APA, Harvard, Vancouver, ISO e altri
6

König, Burkhard, a cura di. Chemical Photocatalysis. Berlin, Boston: DE GRUYTER, 2013. http://dx.doi.org/10.1515/9783110269246.

Testo completo
Gli stili APA, Harvard, Vancouver, ISO e altri
7

Kisch, Horst, a cura di. Semiconductor Photocatalysis. Weinheim, Germany: Wiley-VCH Verlag GmbH & Co. KGaA, 2014. http://dx.doi.org/10.1002/9783527673315.

Testo completo
Gli stili APA, Harvard, Vancouver, ISO e altri
8

Colmenares, Juan Carlos, e Yi-Jun Xu, a cura di. Heterogeneous Photocatalysis. Berlin, Heidelberg: Springer Berlin Heidelberg, 2016. http://dx.doi.org/10.1007/978-3-662-48719-8.

Testo completo
Gli stili APA, Harvard, Vancouver, ISO e altri
9

Muñoz-Batista, Mario J., Alexander Navarrete Muñoz e Rafael Luque, a cura di. Heterogeneous Photocatalysis. Cham: Springer International Publishing, 2020. http://dx.doi.org/10.1007/978-3-030-49492-6.

Testo completo
Gli stili APA, Harvard, Vancouver, ISO e altri
10

Zhang, Zhenglong. Plasmonic Photocatalysis. Singapore: Springer Nature Singapore, 2022. http://dx.doi.org/10.1007/978-981-19-5188-6.

Testo completo
Gli stili APA, Harvard, Vancouver, ISO e altri

Capitoli di libri sul tema "Photocatalysis"

1

Meenakshisundaram, Swaminathan. "Environmental Photocatalysis/Photocatalytic Decontamination". In Handbook of Ecomaterials, 1–16. Cham: Springer International Publishing, 2017. http://dx.doi.org/10.1007/978-3-319-48281-1_65-1.

Testo completo
Gli stili APA, Harvard, Vancouver, ISO e altri
2

Meenakshisundaram, Swaminathan. "Environmental Photocatalysis/Photocatalytic Decontamination". In Handbook of Ecomaterials, 1625–40. Cham: Springer International Publishing, 2019. http://dx.doi.org/10.1007/978-3-319-68255-6_65.

Testo completo
Gli stili APA, Harvard, Vancouver, ISO e altri
3

Kale, Bharat B., Manjiri A. Mahadadalkar e Ashwini P. Bhirud. "Glassy Photocatalysts: New Trend in Solar Photocatalysis". In Visible Light-Active Photocatalysis, 165–89. Weinheim, Germany: Wiley-VCH Verlag GmbH & Co. KGaA, 2018. http://dx.doi.org/10.1002/9783527808175.ch7.

Testo completo
Gli stili APA, Harvard, Vancouver, ISO e altri
4

Zhang, Zhenglong. "Measurement and Analysis of Plasmon-Driven Photocatalysis". In Plasmonic Photocatalysis, 47–61. Singapore: Springer Nature Singapore, 2022. http://dx.doi.org/10.1007/978-981-19-5188-6_6.

Testo completo
Gli stili APA, Harvard, Vancouver, ISO e altri
5

Zhang, Zhenglong. "Fundamentals of Surface Plasmons". In Plasmonic Photocatalysis, 15–23. Singapore: Springer Nature Singapore, 2022. http://dx.doi.org/10.1007/978-981-19-5188-6_3.

Testo completo
Gli stili APA, Harvard, Vancouver, ISO e altri
6

Zhang, Zhenglong. "Plasmon-Driven Catalysis of Molecular Reactions". In Plasmonic Photocatalysis, 63–70. Singapore: Springer Nature Singapore, 2022. http://dx.doi.org/10.1007/978-981-19-5188-6_7.

Testo completo
Gli stili APA, Harvard, Vancouver, ISO e altri
7

Zhang, Zhenglong. "Surface-Plasmon Relaxation Effects". In Plasmonic Photocatalysis, 25–34. Singapore: Springer Nature Singapore, 2022. http://dx.doi.org/10.1007/978-981-19-5188-6_4.

Testo completo
Gli stili APA, Harvard, Vancouver, ISO e altri
8

Zhang, Zhenglong. "Principles of Plasmon-Driven Photocatalysis". In Plasmonic Photocatalysis, 35–46. Singapore: Springer Nature Singapore, 2022. http://dx.doi.org/10.1007/978-981-19-5188-6_5.

Testo completo
Gli stili APA, Harvard, Vancouver, ISO e altri
9

Zhang, Zhenglong. "Electromagnetic Properties of Materials". In Plasmonic Photocatalysis, 5–13. Singapore: Springer Nature Singapore, 2022. http://dx.doi.org/10.1007/978-981-19-5188-6_2.

Testo completo
Gli stili APA, Harvard, Vancouver, ISO e altri
10

Zhang, Zhenglong. "Introduction". In Plasmonic Photocatalysis, 1–3. Singapore: Springer Nature Singapore, 2022. http://dx.doi.org/10.1007/978-981-19-5188-6_1.

Testo completo
Gli stili APA, Harvard, Vancouver, ISO e altri

Atti di convegni sul tema "Photocatalysis"

1

A., Alfiya, Pranavya J. R., Indu M. S e Sajithkumar K. J. "Comparative Assessment of Continuous Flow Photocatalytic Oxidation Reactors for Organic Wastewater Degradation". In 6th International Conference on Modeling and Simulation in Civil Engineering. AIJR Publisher, 2023. http://dx.doi.org/10.21467/proceedings.156.20.

Testo completo
Abstract (sommario):
Photocatalysis is an environmentally friendly technique for removing organic pollutants such as dyes, pesticides, etc. The photo reactors could be of the slurry type and fixed bed type. Continuous flow photocatalytic reactors generally are fixed bed-type reactors. Slurry type designs like loop thin-film slurry flat-plate photoreactors, step aeration slurry reactors etc. were also tried out for continuous flow operations. Continuous flow photocatalytic reactors have become one of the most ensuring methods for the treatment of mass water. However, uniform dispersion of the photocatalyst within the wastewater volume is still existing as a challenge. Different reactor designs like immobilized bed reactors (packed bed reactor and fluidized bed reactor), annular reactor with photocatalyst coated on inner/outer cylinder, photocatalytic membrane reactors, tubular reactors, microreactors, etc. are tested for their efficiency. This review tries to provide a generalized comparison of the relative merits and demerits of these reactor designs and immobilization methods on the degradation of organic contaminants.
Gli stili APA, Harvard, Vancouver, ISO e altri
2

Lu, Yuanwei, Chongfang Ma, Wencai Li, Jianping Sheng e Wei Wang. "The Study of Photocatalytic Degradation of Formaldehyde Under the Action of Mass Transfer". In 2007 First International Conference on Integration and Commercialization of Micro and Nanosystems. ASMEDC, 2007. http://dx.doi.org/10.1115/mnc2007-21025.

Testo completo
Abstract (sommario):
Photocatalysis is an emerging and promising technology for indoor air purification, which has the higher reaction rate at the higher pollutant concentration and vice versa, and the toxic intermediate products were produced meantime. However, the concentration of indoor pollutant is usually very low. So how to improve the photocatalytic reaction rates in indoor contaminant levels in building and to eliminate the intermediate toxic products are the keys of commercialization of this technology. This paper immobilized the TiO2 on the active carbon and analyzed the effect of mass transfer due to the absorption of AC on the photocatalytic reaction rate. The experimental results shown that the photocatalytic reaction rate was improved for the local concentration of contaminants on the surface photocatalyst TiO2 was enhanced by adsorbent activated carbon. With the increase of air stream velocity, the photocatalytic reaction switched from mass transfer control process to photocatalytic reaction control process. The switch point was advanced for the absorption of AC comparing with TiO2 immobilized on the surface of glass. The indoor formaldehyde with low level concentration can be decomposed to the range of indoor air quality standards by the TiO2/AC filter.
Gli stili APA, Harvard, Vancouver, ISO e altri
3

Lepeytre, C., C. Lavaud e G. Serve. "Photocatalytic and Photochemical Degradation of Liquid Waste Containing EDTA". In ASME 2011 14th International Conference on Environmental Remediation and Radioactive Waste Management. ASMEDC, 2011. http://dx.doi.org/10.1115/icem2011-59144.

Testo completo
Abstract (sommario):
The decontamination factor of liquid waste containing 60Co is generally weak. This is due to the presence of complexant molecules. For instance, complexation of EDTA with 60Co decreases efficiency of radioactive waste treatment. The aim of this study was to degrade EDTA in H2O and CO2 and to concentrate free 60Co in order to increase decontamination factor. A first test of radioactive waste treatment by photocatalysis was allowed to increase decontamination factor (60Co) from 16 to 196 with a device requiring to be improved. The present work concerns the first step of the degradation process development with a more powerful device. These first experiments were leaded to follow the only EDTA oxidation. EDTA degradation was carried out by the following Advanced Oxidation Processes (AOP): UV/H2O2 (photochemistry); UV/TiO2 (photocatalysis); UV/TiO2/H2O2. A specific reactor was achieved for this study. The wavelength used was 254 nm (UVC). The photocatalytic degradation of EDTA was carried out with Degussa P-25 titanium dioxide (TiO2), which is a semiconductor photocatalyst. The degradation degree of EDTA and the intermediate products were monitored by TOC and ionic chromatography methods. The effects of various parameters such as pH and the quantity of H2O2 were studied. This allows us to conclude that basic pH slows down EDTA degradation. The study showed that UV/H2O2 process was the most effective treatment process under acid conditions. The rate of EDTA degradation was very high and reached 95% in 120 minutes. The presence of glyoxilic, oxalic, glycolic and formic acids was detected as degradation products. Among the intermediates produced by photochemistry, NO3− ions presence informed of the amine degradations. These results highlighted faster EDTA degradation by photochemistry than photocatalysis.
Gli stili APA, Harvard, Vancouver, ISO e altri
4

Toma, F. L., G. Bertrand, D. Klein, L. M. Berger e S. Thiele. "Photocatalytic Properties of Coatings Sprayed from TiOx and Tin-2Cr2O2n-1 Powders by APS and VPS". In ITSC2004, a cura di Basil R. Marple e Christian Moreau. ASM International, 2004. http://dx.doi.org/10.31399/asm.cp.itsc2004p0946.

Testo completo
Abstract (sommario):
Abstract Titanium dioxide (TiO2) has emerged as an excellent photocatalyst material for environmental purification about two decades ago but only recently few works have focused on the photocatalytic properties of sprayed titanium oxide coatings. So far, the role of oxygen deficiency which can appear as a result of the spray process or by use of titanium suboxide powders on the photocatalytic activity has not been investigated. Also the possible influence of the shear plane structure of titanium suboxides (Magnéli phases) on the photocatalytic activity was not taken into consideration. In the present work, the photocatalytic properties of three powders and coatings sprayed from these powders by APS and VPS are investigated: (1) a commercial fused and crushed titanium oxide powder, (2) an agglomerated and sintered titanium suboxide powder consisting predominantly of Magnéli phases Ti6O11 and Ti5O9, (3) an agglomerated and sintered powder consisting of Ti2Cr2O7 and Ti6Cr2O15 (Magnéli phases in the TiO2- Cr2O3 phase diagram). The phase compositions of the powders and the coatings were investigated by X-ray diffraction. Neither for the spray powders nor for the coatings any ability to reduce the NOx concentration by the photocatalysis was found. From this it is concluded that both oxygen deficiency as well as Magnéli phase structure are not responsible for photocatalytic properties of materials in the Ti-O phase diagram.
Gli stili APA, Harvard, Vancouver, ISO e altri
5

Rasponi, Marco, Tania Ullah, Richard Gilbert, Gianfranco B. Fiore e Todd Thorsen. "A Microfluidic Device for Flow-Through Blood Oxygenation by Photocatalytic Action". In ASME 2009 Summer Bioengineering Conference. American Society of Mechanical Engineers, 2009. http://dx.doi.org/10.1115/sbc2009-206652.

Testo completo
Abstract (sommario):
The breakthrough work of Fujishima and Honda in 1972 [1], in which they achieved ultraviolet light-induced water cleavage with the use of titanium dioxide (TiO2) in an electrochemical cell, has drawn considerable attention in recent years to the “acceleration of a photoreaction by the presence of a catalyst” [2] or photocatalysis. Research on photocatalysis has explored the decomposition of organic pollutants and microorganisms, the superhydrophilic self-cleaning properties of surfaces, and the photosplitting of water, among other applications. Semiconductors can act as photocatalysts because of their electronic structure and TiO2, in particular, has been a popular choice. It is non-toxic and mechanically stable, can be fabricated at low-cost, and the anatase phase of TiO2 has a bandgap of approximately 3.2 eV, ideal for excitation by light in the ultraviolet range.
Gli stili APA, Harvard, Vancouver, ISO e altri
6

Zhuo Luo, Shiying Zhang, Difa Xu, Yang You e Zhongxin Lin. "Composite photocatalyst of Glass-Microspheres/TiO2:Synthesis and photocatalysis activity". In 2011 International Conference on Remote Sensing, Environment and Transportation Engineering (RSETE). IEEE, 2011. http://dx.doi.org/10.1109/rsete.2011.5966097.

Testo completo
Gli stili APA, Harvard, Vancouver, ISO e altri
7

Arakawa, Hironori, Zhigang Zou, Kazuhiro Sayama e Ryu Abe. "Solar Hydrogen Production: Direct Water Splitting Into Hydrogen and Oxygen by New Photocatalysts Under Visible Light Irradiation". In ASME 2003 International Solar Energy Conference. ASMEDC, 2003. http://dx.doi.org/10.1115/isec2003-44301.

Testo completo
Abstract (sommario):
The photocatalytic splitting of water into hydrogen and oxygen using solar energy is one of the most attractive renewable sources of hydrogen fuel. Therefore, considerable efforts have been paid in developing photocatalysts capable of using visible light, which accounts for about 43% of the solar energy. However such a photocatalyst has not been developed so far. We have developed a new Ni-doped indium-tantalum oxide photocatalyst, In1-xNixTaO4 (x = 0.0∼0.2), which induced direct splitting of water into stoichiometric amount of oxygen and hydrogen under visible light irradiation with a quantum yield of about 0.66% at 420.7 nm. We have also developed a new two-step water splitting system using two different semiconductor photocatalysts, Pt/WO3 photocatalyst for oxygen evolution and Pt/SrTiO3(Cr-Ta-doped) photocatalyst for hydrogen evolution, and a redox mediator, I−/IO3−, mimicking the Z-scheme mechanism of the natural photosynthesis. The quantum yield of this system was about 0.1% at 420.7nm. Both photocatalytic methods are the first examples for visible light water splitting system in the world.
Gli stili APA, Harvard, Vancouver, ISO e altri
8

Lu, Yuanwei, Dinghui Wang e Chongfang Ma. "Study on Effects of Nano-Photocatalysis and Non-Thermal Plasma on the Removal of Indoor HCHO". In ASME 2009 Second International Conference on Micro/Nanoscale Heat and Mass Transfer. ASMEDC, 2009. http://dx.doi.org/10.1115/mnhmt2009-18510.

Testo completo
Abstract (sommario):
Photocatalysis is an emerging and promising technology for indoor air purification. This photocatalytic oxidation (PCO) method is effective in the case of a higher pollutant concentration, but its wide application in indoor air purification is limited due to the low level of indoor air contaminants. In order to improve the removal of pollutants in indoor air, we have evaluated the photocatalytic performance over the nanosized TiO2 particles immobilized on the surface of an activated carbon (AC) filter for the removal of formaldehyde (HCHO). However the pollutant removal capacity is low at the low level of indoor HCHO over the TiO2/AC film because the predominant influence of residence time during this reaction. In order to improve the photocatalytic removal amount of formaldehyde (HCHO) in indoor air, we studied the combining effect of photocatalysis technology with a non-thermal plasma (NTP) technology on the removal of in door HCHO. Two different plasma electrode configurations, that is wire-to-plate and needle-to-plate electrode configuration, were built and the removal of HCHO was studied by experiment. The experimental results showed that the wire-to-plate electrode configuration is more effective for the HCHO removal than the needle-to-plate electrode configurations. The experimental results using wire-to-plate electrode configuration showed that the removal of HCHO can be enhanced and the removal amount of indoor HCHO can be improved by the combination of PCO and NTP and the combination of PCO and NTP showed the synergetic effect for the indoor HCHO removal. So the combination of PCO and NTP might be a good route for the practical application of photocatalytic technology in indoor air purification.
Gli stili APA, Harvard, Vancouver, ISO e altri
9

Liu, Peng, Zhiyuan Yang e Pan Ran. "Preparation and photocatalysis properties of La-doped nano-NiO novel photocatalyst". In Second International Conference on Smart Materials and Nanotechnology in Engineering, a cura di Jinsong Leng, Anand K. Asundi e Wolfgang Ecke. SPIE, 2009. http://dx.doi.org/10.1117/12.840080.

Testo completo
Gli stili APA, Harvard, Vancouver, ISO e altri
10

Un, Ieng Wai, Yonatan Dubi e Yonatan Sivan. "Photothermal nonlinearity in photocatalysis". In CLEO: Fundamental Science. Washington, D.C.: Optica Publishing Group, 2023. http://dx.doi.org/10.1364/cleo_fs.2023.ftu4c.6.

Testo completo
Abstract (sommario):
We study the importance of nonlinear photothermal effects in plasmon-assisted photocatalysis and show that any claim for dominance of non-thermal electrons in plasmon-assisted photocatalysis must account for this photothermal nonlinear mechanism.
Gli stili APA, Harvard, Vancouver, ISO e altri

Rapporti di organizzazioni sul tema "Photocatalysis"

1

Fox, Marye A. Surface Mediated Photocatalysis. Fort Belvoir, VA: Defense Technical Information Center, dicembre 1987. http://dx.doi.org/10.21236/ada188882.

Testo completo
Gli stili APA, Harvard, Vancouver, ISO e altri
2

Gupta, Arunava, e Peter E. Prevelige. Multicomponent Protein Cage Architectures for Photocatalysis. Office of Scientific and Technical Information (OSTI), gennaio 2016. http://dx.doi.org/10.2172/1233559.

Testo completo
Gli stili APA, Harvard, Vancouver, ISO e altri
3

Douglas, Trevor. Multicomponent Protein Cage Architectures for Photocatalysis. Office of Scientific and Technical Information (OSTI), novembre 2014. http://dx.doi.org/10.2172/1172771.

Testo completo
Gli stili APA, Harvard, Vancouver, ISO e altri
4

Chang, A. Plasmonics-Enhanced Photocatalysis for Water Decontamination. Office of Scientific and Technical Information (OSTI), ottobre 2019. http://dx.doi.org/10.2172/1573141.

Testo completo
Gli stili APA, Harvard, Vancouver, ISO e altri
5

Batzill, Matthias. Photocatalysis of Modified Transition Metal Oxide Surfaces. Office of Scientific and Technical Information (OSTI), febbraio 2018. http://dx.doi.org/10.2172/1423046.

Testo completo
Gli stili APA, Harvard, Vancouver, ISO e altri
6

Thomas E. Mallouk. PHOTOELECTROCHEMISTRY AND PHOTOCATALYSIS IN NANOSCALE INORGANIC CHEMICAL SYSTEMS. Office of Scientific and Technical Information (OSTI), maggio 2007. http://dx.doi.org/10.2172/907952.

Testo completo
Gli stili APA, Harvard, Vancouver, ISO e altri
7

Chuang, Steven S. C. CO2 SEQUESTRATION AND RECYCLE BY PHOTOCATALYSIS WITH VISIBLE LIGHT. Office of Scientific and Technical Information (OSTI), dicembre 1999. http://dx.doi.org/10.2172/799755.

Testo completo
Gli stili APA, Harvard, Vancouver, ISO e altri
8

Chuang, Steven S. C. CO2 SEQUESTRATION AND RECYCLE BY PHOTOCATALYSIS WITH VISIBLE LIGHT. Office of Scientific and Technical Information (OSTI), ottobre 2001. http://dx.doi.org/10.2172/802825.

Testo completo
Gli stili APA, Harvard, Vancouver, ISO e altri
9

Asenath-Smith, Emily, Emma Ambrogi, Eftihia Barnes e Jonathon Brame. CuO enhances the photocatalytic activity of Fe₂O₃ through synergistic reactive oxygen species interactions. Engineer Research and Development Center (U.S.), settembre 2021. http://dx.doi.org/10.21079/11681/42131.

Testo completo
Abstract (sommario):
Iron oxide (α-Fe₂O₃, hematite) colloids were synthesized under hydrothermal conditions and investigated as catalysts for the photodegradation of an organic dye under broad-spectrum illumination. To enhance photocatalytic performance, Fe₂O₃ was combined with other transition-metal oxide (TMO) colloids (e.g., CuO and ZnO), which are sensitive to different regions of the solar spectrum (far visible and ultraviolet, respectively), using a ternary blending approach for compositional mixtures. For a variety of ZnO/Fe₂O₃/CuO mole ratios, the pseudo-first-order rate constant for methyl orange degradation was at least double the sum of the individual Fe₂O₃ and CuO rate constants, indicating there is an underlying synergy governing the photocatalysis reaction with these combinations of TMOs. A full compositional study was carried out to map the interactions between the three TMOs. Additional experiments probed the identity and role of reactive oxygen species and elucidated the mechanism by which CuO enhanced Fe₂O₃ photodegradation while ZnO did not. The increased photocatalytic performance of Fe2O3 in the presence of CuO was associated with hydroxyl radical ROS, consistent with heterogeneous photo-Fenton mechanisms, which are not accessible by ZnO. These results imply that low-cost photocatalytic materials can be engineered for high performance under solar illumination by selective pairing of TMOs with compatible ROS.
Gli stili APA, Harvard, Vancouver, ISO e altri
10

Eckstein, James N., e Kenneth S. Suslick. 2011 Final Report - Nano-Oxide Photocatalysis for Solar Energy Conversion. Office of Scientific and Technical Information (OSTI), ottobre 2011. http://dx.doi.org/10.2172/1027507.

Testo completo
Gli stili APA, Harvard, Vancouver, ISO e altri
Offriamo sconti su tutti i piani premium per gli autori le cui opere sono incluse in raccolte letterarie tematiche. Contattaci per ottenere un codice promozionale unico!

Vai alla bibliografia