Academic literature on the topic 'Photocatalysys'

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Journal articles on the topic "Photocatalysys"

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Chuaicham, Chitiphon, Jirawat Trakulmututa, Kaiqian Shu, Sulakshana Shenoy, Assadawoot Srikhaow, Li Zhang, Sathya Mohan, Karthikeyan Sekar, and Keiko Sasaki. "Recent Clay-Based Photocatalysts for Wastewater Treatment." Separations 10, no. 2 (January 22, 2023): 77. http://dx.doi.org/10.3390/separations10020077.

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Photocatalysis is a remarkable methodology that is popular and applied in different interdisciplinary research areas such as the degradation of hazardous organic contaminants in wastewater. In recent years, clay-based photocatalyst composites have attracted significant attention in the field of photocatalysis owing to their abundance, excellent light response ability, and stability. This review describes the combination of clay with focusing photocatalysts such as TiO2, g-C3N4, and Bi-based compounds for degrading organic pollutants in wastewater. Clay-based composites have more active surface sites, resulting in inhibited photocatalyst particle agglomeration. Moreover, clay enhances the creation of active radicals for organic pollutant degradation by separating photogenerated electrons and holes. Thus, the functions of clay in clay-based photocatalysts are not only to act as a template to inhibit the agglomeration of the main photocatalysts but also to suppress charge recombination, which may lengthen the electron–hole pair’s lifespan and boost degrading activity. Moreover, several types of clay-based photocatalysts, such as the clay type and main photocatalyst, were compared to understand the function of clay and the interaction of clay with the main photocatalyst. Thus, this study summarizes the recent clay-based photocatalysts for wastewater remediation and concludes that clay-based photocatalysts have considerable potential for low-cost, solar-powered environmental treatment.
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Rocha, Rafael Lisandro P., Luzia Maria C. Honorio, Roosevelt Delano de S. Bezerra, Pollyana Trigueiro, Thiago Marinho Duarte, Maria Gardennia Fonseca, Edson C. Silva-Filho, and Josy A. Osajima. "Light-Activated Hydroxyapatite Photocatalysts: New Environmentally-Friendly Materials to Mitigate Pollutants." Minerals 12, no. 5 (April 23, 2022): 525. http://dx.doi.org/10.3390/min12050525.

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This review focuses on a reasoned search for articles to treat contaminated water using hydroxyapatite (HAp)-based compounds. In addition, the fundamentals of heterogeneous photocatalysis were considered, combined with parameters that affect the pollutants’ degradation using hydroxyapatite-based photocatalyst design and strategies of this photocatalyst, and the challenges of and perspectives on the development of these materials. Many critical applications have been analyzed to degrade dyes, drugs, and pesticides using HAp-based photocatalysts. This systematic review highlights the recent state-of-the-art advances that enable new paths and good-quality preparations of HAp-derived photocatalysts for photocatalysis.
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You, Wei. "Research Progresses and Development Trends of High-Efficacy Photocatalysts." Applied Mechanics and Materials 496-500 (January 2014): 532–35. http://dx.doi.org/10.4028/www.scientific.net/amm.496-500.532.

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Progresses of research on high-efficacy photocatalyst were introduced in this paper. Firstly, efficiency-strengthening methods of TiO2-serie photocatalysts were summarized basing on collected literatures, including photosensitization, alloying, moreover, novel photocatalysis materials and technologies and probable development tendencies in the future were introduced, such as broad-spectrum photocatalysts, broad-energy and energy-sensitive catalysts and high-efficacy controllable high-power photocatalysis materials and equipments.
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Prakash, Jai. "Mechanistic Insights into Graphene Oxide Driven Photocatalysis as Co-Catalyst and Sole Catalyst in Degradation of Organic Dye Pollutants." Photochem 2, no. 3 (August 17, 2022): 651–71. http://dx.doi.org/10.3390/photochem2030043.

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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.
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Li, Xue, Ulla Simon, Maged F. Bekheet, and Aleksander Gurlo. "Mineral-Supported Photocatalysts: A Review of Materials, Mechanisms and Environmental Applications." Energies 15, no. 15 (August 2, 2022): 5607. http://dx.doi.org/10.3390/en15155607.

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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.
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Teye, Godfred Kwesi, Jingyu Huang, Yi Li, Ke Li, Lei Chen, and Williams Kweku Darkwah. "Photocatalytic Degradation of Sulfamethoxazole, Nitenpyram and Tetracycline by Composites of Core Shell g-C3N4@ZnO, and ZnO Defects in Aqueous Phase." Nanomaterials 11, no. 10 (October 4, 2021): 2609. http://dx.doi.org/10.3390/nano11102609.

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The synthesis of photocatalysts with high charge separation and transfer efficiency are of immense significance in the process of using photocatalysis technology for wastewater treatment. In this study core shell g-C3N4@ZnO, and ZnO defects photocatalysts presented an improved morphology in its characterization using techniques such as SEM, DRS, PL, MS, EIS, and XRD, and enhanced photodegradation of sulfamethoxazole, Nitenpyram and Tetracycline. Different composites were obtained as confirmed by the various characterization techniques studied, including core shell g-C3N4@ZnO, and ZnO defects photocatalyst. The synthesized photocatalysts showed high visible light absorption efficiency within a range of ~655 to 420 nm. Core shell g-C3N4@ZnO, and ZnO defects photocatalysts demonstrated high photocatalytic activity ascribed to high load separation and transition as shown in PL, Photocurrent reaction and EIS. It is understandable that core shell g-C3N4@ZnO, and ZnO defects photocatalysts have been confirmed to be one of the ultimate promising entrants for photocatalyst scheming.
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Li, Bin, Xin Yi Wang, and Xiao Gang Yang. "Effect of Mixing Ratio and Doping Acid on the Photocatalytic Properties of PANI-BiVO4 Composites." Key Engineering Materials 727 (January 2017): 866–69. http://dx.doi.org/10.4028/www.scientific.net/kem.727.866.

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BiVO4 photocatalyst prepared by hydrothermal method was mixed with polyaniline (PANI). The phase structure, morphology and optical properties of PANI-BiVO4 photocatalysts were analyzed through X-ray diffraction (XRD), scanning electron microscopy (SEM) and UV-Vis diffuse reflectance spectroscopy (DRS). The results showed that the optimal preparation conditions of composite photocatalyst were 0.5wt.% PANI mixing ratio and H3PO4 as doping acid. The photocatalysis degradation rate is the highest. This new heterogeneous structure photocatalyst is expected to show considerably potential applications in solar-driven environmental pollution cleanup.
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Gao, Lan, Elyes Nefzaoui, Frédéric Marty, Mazen Erfan, Stéphane Bastide, Yamin Leprince-Wang, and Tarik Bourouina. "TiO2-Coated ZnO Nanowire Arrays: A Photocatalyst with Enhanced Chemical Corrosion Resistance." Catalysts 11, no. 11 (October 27, 2021): 1289. http://dx.doi.org/10.3390/catal11111289.

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Photocatalysis is proven to be the most efficient and environmentally friendly method for the degradation of organic pollutants in water purification. To meet the requirement of large-scale water treatment, there are two important points: One is the lifetime and chemical stability of the photocatalyst material, especially in the complex and harsh aqueous conditions. The other is the ease of synthesis of such photocatalysts with specific nano-morphology. In this work, two common photocatalyst materials, zinc oxide (ZnO) and titanium dioxide (TiO2), are selected to form more sustainable photocatalysts with high chemical stability. This involves the combination of both TiO2 and ZnO in a two-step simple synthesis method. It appears advantageous to exploit the conformal deposition of atomic layer deposition (ALD) to achieve nanometer-thick TiO2 coating on ZnO nanowires (NWs) with a high aspect ratio, which are firmly anchored to a substrate and exhibit a large specific surface area. The high chemical stability of the ALD TiO2 coating has been investigated in detail and proven to be effective under both strong acid and strong alkaline aqueous solutions. In addition, photocatalysis experiments with organic dyes show that via this simple two-step synthesis method, the produced ZnO/TiO2 tandem photocatalysts does indeed exhibit improved chemical stability in a harsh environment, while allowing efficient photodegradation.
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Alalm, Mohamed Gar, Ridha Djellabi, Daniela Meroni, Carlo Pirola, Claudia Letizia Bianchi, and Daria Camilla Boffito. "Toward Scaling-Up Photocatalytic Process for Multiphase Environmental Applications." Catalysts 11, no. 5 (April 28, 2021): 562. http://dx.doi.org/10.3390/catal11050562.

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Recently, we have witnessed a booming development of composites and multi-dopant metal oxides to be employed as novel photocatalysts. Yet the practical application of photocatalysis for environmental purposes is still elusive. Concerns about the unknown fate and toxicity of nanoparticles, unsatisfactory performance in real conditions, mass transfer limitations and durability issues have so far discouraged investments in full-scale applications of photocatalysis. Herein, we provide a critical overview of the main challenges that are limiting large-scale application of photocatalysis in air and water/wastewater purification. We then discuss the main approaches reported in the literature to tackle these shortcomings, such as the design of photocatalytic reactors that retain the photocatalyst, the study of degradation of micropollutants in different water matrices, and the development of gas-phase reactors with optimized contact time and irradiation. Furthermore, we provide a critical analysis of research–practice gaps such as treatment of real water and air samples, degradation of pollutants with actual environmental concentrations, photocatalyst deactivation, and cost and environmental life-cycle assessment.
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Gu, Zhanyong, Mengdie Jin, Xin Wang, Ruotong Zhi, Zhenghao Hou, Jing Yang, Hongfang Hao, et al. "Recent Advances in g-C3N4-Based Photocatalysts for NOx Removal." Catalysts 13, no. 1 (January 13, 2023): 192. http://dx.doi.org/10.3390/catal13010192.

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Nitrogen oxides (NOx) pollutants can cause a series of environmental issues, such as acid rain, ground-level ozone pollution, photochemical smog and global warming. Photocatalysis is supposed to be a promising technology to solve NOx pollution. Graphitic carbon nitride (g-C3N4) as a metal-free photocatalyst has attracted much attention since 2009. However, the pristine g-C3N4 suffers from poor response to visible light, rapid charge carrier recombination, small specific surface areas and few active sites, which results in deficient solar light efficiency and unsatisfactory photocatalytic performance. In this review, we summarize and highlight the recent advances in g-C3N4-based photocatalysts for photocatalytic NOx removal. Firstly, we attempt to elucidate the mechanism of the photocatalytic NOx removal process and introduce the metal-free g-C3N4 photocatalyst. Then, different kinds of modification strategies to enhance the photocatalytic NOx removal performance of g-C3N4-based photocatalysts are summarized and discussed in detail. Finally, we propose the significant challenges and future research topics on g-C3N4-based photocatalysts for photocatalytic NOx removal, which should be further investigated and resolved in this interesting research field.
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Dissertations / Theses on the topic "Photocatalysys"

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

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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.
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Iervolino, Giuseppina. "Advanced oxidation processes for food industry wastewater valorization and treatment." Doctoral thesis, Universita degli studi di Salerno, 2017. http://hdl.handle.net/10556/2616.

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2015 - 2016
The research of new eco-friendly technologies that enable the production of energy is nowadays one of the topics of greatest interest to the scientific community. The population has chosen to break free from the use of fossil fuels, and this leads to the study and development of processes for the production of clean energy starting from biomass. However, at the same time, the concern of the industry is also the disposal and treatment of wastewater. Starting from these considerations, it is advisable to develop processes that, under mild conditions, allow to obtain interesting hydrogen or methane yields. This objective could be achieved through the use advanced oxidation processes (AOPs), such as heterogeneous photocatalysis, photo-Fenton like reaction and photoelectrocatalysis. So, an interesting approach is to explore, in parallel to wastewater treatment, the possibility to produce also an energy source such as hydrogen and/or methane from the degradation of organic substance present in wastewater by AOPs. Considering the characteristic of food industries wastewaters, it is interesting to evaluate the performances of advanced oxidation processes for their treatment aimed to the valorization, through the conversion of specific substances (sugars), in order to obtain compounds with high energetic value, but also for removing substances hardly biodegradable (such as food dyes) that could be present in these industry wastewaters. In this PhD thesis it has been studied the performances of the photocatalytic process for the hydrogen production from food industries wastewaters. In particular, starting from synthetic solution containing glucose, it was evaluated the effect of the presence of noble metals on the semiconductor surface and the effect of the photoactive support (TiO2). Subsequently, providing for the application of heterogeneous photocatalysis to industrial level, the study has been directed to the formulation of a noble metal free photocatalyst with good performances in the production of hydrogen and in the degradation of the sugars present in the solutions. The final formulation was represented by LaFeO3 (a perovskite with semiconducting properties) prepared by combustion flame method. To improve the performances under visible light, LaFeO3 was modified with Ru (Ru-LaFeO3), whose cost is much lower than those of Pd, Pt or Au. Always perspective of the application of the process to industrial level, it was developed a structured photocatalyst for solving the problems related to the photocatalyst separation after the treatment. In particular it was studied the efficiency of magnetic Fe2O3 as support for Ru-LaFeO3. It was also investigated the photoelectrocatalytic process for the hydrogen production, considering the general aspects of the process, the advantages and in particular the attention has been focused on the electrodeposition process for the synthesis of Fe2O3 based photoanodes. Finally, the aim has been the application of the photocatalytic process on a real wastewater coming from the washing process of the fruit (especially cherries). It was not underestimated the presence of food dyes in these types of wastewater. For this reason it was evaluated the efficiency of photo-Fenton process in the removal of several food dyes (such as Red Allura and Tartrazine) using LaFeO3 deposited on corundum monoliths. In addition, it has been evaluated the possibility to couple the photocatalytic process (used for the valorization of the wastewater through the production of hydrogen) to the optimized photo-Fenton system to completely remove the not-biodegradable substances still present in the wastewaters recovered after the photocatalytic treatment using Ru-LaFeO3 supported on magnetic Fe2O3 particles. [edited by author]
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Hathway, Timothy Lee. "Titanium dioxide photocatalysis studies of the degradation of organic molecules and characterization of photocatalysts using mechanistic organic chemistry /." [Ames, Iowa : Iowa State University], 2009. http://gateway.proquest.com/openurl?url_ver=Z39.88-2004&rft_val_fmt=info:ofi/fmt:kev:mtx:dissertation&res_dat=xri:pqdiss&rft_dat=xri:pqdiss:3369929.

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Ran, Rong. "Preparation and Optimization of Novel Visible-Light-Active Photocatalysts for Waste-Water Treatment." Thesis, Université d'Ottawa / University of Ottawa, 2016. http://hdl.handle.net/10393/34152.

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Photocatalysis is a series of advanced light-induced redox reaction processes resulting in the degradation and mineralization of organic pollutants in the presence of oxygen and water. Due to their capability to destroy contaminants under mild conditions, photocatalytic processes have attracted considerable attention in the field of waste-water treatment. However, photocatalytic reactions using the traditional TiO2 photocatalyst suffer from low energy efficiencies under solar irradiation. This low efficiency in the utilization of solar energy lies in its incapability in absorbing visible lights and also the high recombination rate of photo-excited species in photocatalysts. In addition, difficulties in the separation of fluids from micro- or nano-scale catalysts in large scale systems substantially impact cost efficiency in practice. In this thesis, strategies are explored which address these issues in order to improve the feasibility of solar photocatalysis. Two branches of photocatalytic transition metal-oxide semiconductor materials are investigated, namely bismuth-based and silver-based multi-phase heterogeneous photocatalysts. This research is focused on the design of visible-light-active metal-oxide photocatalysts to increase the absorption of visible light and to decrease the rates of electron-hole recombination, resulting in a high photocatalytic efficiency in regards to the degradation of organic pollutants. BiVO4 powder, synthesized from freshly made potassium metavanadate was prepared via hydrothermal treatment, characterized and experimentally investigated for the degradation of rhodamine B under visible light irradiation. The crystal structures and the specific surface areas of the composites, based on BiVO4 single phase crystal structures, are discussed. A multi-phase silver species (Ag2O/Ag3VO4/Ag4V2O7) photocatalyst was synthesized by adjusting the molar ratio of silver to vanadium (Ag to V) via hydrothermal method. The stabilities of as-prepared silver species composites regarding crystal structural changes due to photocatalytic reactions are investigated. Multi-phase silver species composites assisted with graphene oxide (GO-Ag2O/Ag3VO4/AgVO3) were synthesized at room temperature, and exhibited high visible-light photocatalytic activities regarding the degradation of model organic pollutants. The effect of graphene oxide addition on the photoactivity and on the photocorrosion of silver species composites under VLI is explored. The synergistic roles of each individual phase incorporated into the multi-phase composites are discussed regarding the photocatalytic performance.
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Dezani, Chloé. "Photocatalyse hétérogène en réacteurs ouverts pour la gestion de la ressource solaire : expérimentations sur différents médias et modélisation." Thesis, Perpignan, 2020. http://www.theses.fr/2020PERP0018.

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La présence des micropolluants dans l’environnement est reconnue comme un problème potentiel de santé publique qu’il convient de maitriser afin, d’une part de mettre en place une politique de circularité de l’eau, et d’autre part, de limiter leur dissémination et ainsi leurs effets sur les écosystèmes. Ces substances sont d’origine anthropique et sont pour la plupart bio-récalcitrantes donc partiellement ou non éliminées par les installations de traitement d’eaux usées qui reposent sur l’activité biologique. La photocatalyse hétérogène fait partie des procédés d’oxydation avancée développés spécifiquement pour le traitement des micropolluants. Ce procédé a la particularité de pouvoir utiliser l’énergie solaire comme source énergétique principale ce qui en fait un candidat d’intérêt dans une démarche de développement durable. Les caractéristiques de la ressource solaire, fluctuations/intermittence, impactent directement la capacité de traitement du procédé, et doivent être prises en compte dans sa gestion. Dans la littérature, cette prise en compte pour opérer le procédé porte exclusivement sur les réacteurs dits fermés. Le processus de traitement est alors interrompu la nuit dans les pilotes solaires étudiés. Lors du développement d’un procédé en mode continu, la gestion de l’intermittence s’impose afin de pouvoir assurer un traitement continu de l’effluent. Cette thèse vise à développer un modèle de représentation de la capacité de traitement d’un réacteur fonctionnant sur le principe de la photocatalyse hétérogène. Cette étape est indispensable pour le dimensionnement et pilotage de procédés solaires. Dans une deuxième partie, l’étude se focalise sur la faisabilité d’une technologie de gestion de l’intermittence basée sur un matériau composite adsorbant/photo-catalyseur. L’adsorbant permet de stocker les polluants lorsque la ressource est insuffisante et le photo-catalyseur vise à dégrader les polluants en phase liquide et en phase solide, ce qui revient à régénérer l’adsorbant lors des périodes d’ensoleillement. Ces deux études s’inscrivent dans l’objectif, sur le long terme, de permettre la mise en œuvre d’un procédé de photocatalyse hétérogène solaire en mode continu, capable d’opérer un traitement permanent malgré les fluctuations et l’intermittence solaires. Le premier objectif a consisté à développer un modèle de représentation du transfert radiatif dans les différents milieux hétérogènes réactifs étudiés afin de déterminer la puissance locale absorbée par ces derniers. Dans le cas de particules de photo-catalyseur en suspension, la littérature est relativement fournie, en comparaison des géométries plus complexes, pour lesquelles les études sont moins avancées. Les photo-catalyseurs testés, que sont le dioxyde de titane sous forme particulaire ou déposé sur une mousse alvéolaire macroporeuse inerte, ont ainsi nécessité de développer une approche spécifique. Le second objectif a consisté à déterminer la cinétique de photo-dégradation - dépendant principalement de la concentration en polluant d’étude et de la puissance locale absorbée - à partir d’expérimentations en réacteur fermé. Les vitesses locales des couples polluant, la caféine/photo-catalyseurs, sous forme particulaire ou supportée, ont été déterminées. Connaissant les modèles hydrodynamiques des réacteurs étudiés, un réacteur piston et un réacteur ouvert parfaitement agité, le modèle de représentation de la capacité de traitement, couplant l’ensemble des étapes énoncées (transfert radiatif, cinétique, convection), a été validé et appliqué à des expérimentations de photo-dégradation en réacteur ouvert soumis à des consignes dynamiques représentatives de l’ensoleillement réel. Le dernier objectif, dit exploratoire, a été de tester le matériau composite dans un photo-réacteur ouvert soumis à des cycles sans lumière/avec lumière. La capacité de ce dernier à opérer un traitement photo-catalytique et à s’auto-régénérer au cours des cycles a été montrée
The occurrence of micropollutants in water is recognized as a public health concern that needs to be addressed. The challenge is both to implement water reuse and to prevent micropollutants from being disseminated in the environment, and therefore to stop their detrimental effects. These so-called emerging contaminants are anthropogenic and most of them are non-biodegradable. Therefore, conventional biological treatments of wastewater treatment plants are not appropriate. Heterogeneous photocatalysis belongs to the advanced oxidation processes developed specifically for micropollutants’ removal. This process can be operated under solar light which makes it a relevant environmental-friendly option. Solar characteristics, such as light fluctuation and intermittency, have a direct impact on the process’s treatment capacity and need to be considered for its management. In the literature, photocatalytic reactors are mainly operated in a batch mode, which implies stopping treatment during the night. The development of continuous-mode reactors requires finding solutions to deal with light intermittency. This thesis aims, in a first part, to develop a model to predict the process’s treatment capacity of a continuous-mode reactor based on heterogeneous photocatalysis. This step is essential for the scaling and control of solar processes for micropollutants’ removal. The study also focuses, in a second part, on the reliability of a technology for intermittency management. This technology is based on a composite material made of an adsorbent and a photocatalyst. The adsorbent allows to store micropollutants when light is not enough, during the night or cloudy events. The photocatalyst enables the contaminants to be degraded, both in the liquid and solid phases, in order to operate the liquid treatment as well as regenerating the adsorbent. These two studies aim to bring knowledge to the development of continuous-mode solar processes, that can operate despite solar intermittency and light fluctuations. The first step to reach the previous purposes, is to develop a model to represent the radiation field inside the photoreactor for the two studied photocatalysts with the aim of calculating the local volumetric rate of photon absorption (LVRPA). In case of photocatalysts in suspension, literature about modelling radiative transfer is rich in comparison with supported photocatalysts. Therefore, the two tested media, titanium dioxide in suspension and titanium dioxide supported on an inert macroporous foam, require specific methodologies. The second step is to determine the kinetics model, which is a function of the pollutant concentration and the LVRPA, thanks to batch-mode experiments. Local kinetics of the different pairs “pollutant/photocatalysts” (caffeine/suspension or foam) are determined. Two reactors are studied: a plug-flow one and a perfectly well-mixed one. Knowing the models of their hydrodynamics and their kinetics, the combination of all of them is validated and then applied on photo-degradation experiments of caffeine under dynamic light operating conditions, representative of real solar light. The last purpose is to test the composite material in a continuous-mode photoreactor submitted to cycles alternating light and dark periods. The ability of the composite to degrade and regenerate is evidenced
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Nascimento, Ulisses Magalhães. "Preparação, caracterização e testes catalíticos de um fotocatalisador magnético (Fe3O4/TiO2) na degradação de um poluente-modelo: acid blue 9." Universidade de São Paulo, 2013. http://www.teses.usp.br/teses/disponiveis/75/75132/tde-23042013-112144/.

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A aplicação de semicondutores no tratamento de água e efluentes líquidos é uma tecnologia de remediação ambiental promissora, em especial para poluentes orgânicos. Entre os vários semicondutores que também são fotocatalisadores, o TiO2 é amplamente usado em aplicações ambientais, por ser inerte biológica e quimicamente, ter elevado potencial de oxidação, baixo custo e estabilidade frente à corrosão. Entretanto, o TiO2 também tem algumas desvantagens, tais como: ele é excitado apenas por luz UV e requer uma operação unitária adicional (por exemplo, filtração ou centrifugação) para o reuso do catalisador. Para contornar estas limitações, usou-se um procedimento simples para a síntese de um fotocatalisador magnético (Fe3O4/TiO2) com alta área superficial específica e atividade catalítica, quando comparado com o TiO2 P25 da Evonik. O fotocatalisador foi sintetizado através de um procedimento em três etapas: (1) Partículas α-Fe2O3 foram obtidas por precipitação de uma solução de FeCl3.6H2O 0.01 mol L-1, que foi submetida a uma hidrólise forçada à 100°C por 48 h; (2) Partículas de α-Fe2O3/TiO2 foram obtidas por heterocoagulação de oxi-hidróxidos de Ti(IV) sobre as partículas de α-Fe2O3, as quais foram calcinada a 500°C por 2 h; e (3) As partículas \"casaca/caroço\" do fotocatalisador foram obtidas por calcinação a 400°C por 1 h sob atmosfera redutora (H2). A atividade fotocatalítica do material sintetizado foi avaliada aplicando-o no descoramento de uma solução do corante Azul Ácido 9 (C.I. 42090). Os efeitos do pH e da concentração de catalisador foram estimados por meio de um planejamento fatorial 22. Foi obtido um fotocatalisador com área superficial específica de 202 m2 g-1, facilmente separável do meio reacional em aproximadamente 2 min com o auxílio de um ímã. O fotocatalisador apresentou absorção em toda a região do visível. A maior remoção de cor (54%) foi obtida com pH 3,0, 1,0 g L-1 de catalisador e 2 horas de reação.
The use of semiconductors for treating polluted waters and wastewaters is a promising environmental remediation technology, especially for organic pollutants. Among the several semiconductors that are also photocatalysts, TiO2 is extensively used for environmental application, due to its biological and chemical inertness, high oxidation power, low cost, and stability regarding corrosion. However, TiO2 also has some disadvantages, such as: it is only UV-excited and requires an additional unit operation (e.g. filtration or centrifugation) for reuse purposes. In order to work around those limitations, a simple procedure for synthesizing a magnetic photocatalyst (Fe3O4/TiO2), with high specific surface area and good photocatalytic activity when compared to Evonik\'s TiO2 P25, was used. The photocatalyst was synthesized in a three-step procedure: (1) α-Fe2O3 particles were obtained, by precipitation, from FeCl3.6H2O 0.01 mol L-1, which underwent a forced acid hydrolysis at 100°C for 48 h; (2) α-Fe2O3/TiO2 particles were obtained, by heterocoagulation, of Ti(IV) oxide species on the α-Fe2O3, followed by calcination at 500°C for 2 h; and (3) The core/shell photocatalyst particles were obtained by calcination the α-Fe2O3/TiO2 particles at 400°C for 1 h under reducing atmosphere (H2). The photocatalytic activity of the synthesized material was assessed by the color removal of an Acid Blue 9 (C.I. 42090) dye solution. pH and catalyst dosage effects were estimated by a 22 factorial design. Fe3O4/TiO2 core/shell particles with specific surface area of 202 m2 g-1were obtained. They were easily separated from the reaction medium, in approximately 2 min, with the aid of a magnet. The photocatalyst absorbed radiation throughout the visible spectrum. The greatest color removal (54%) was achieved with pH 3.0, 1.0 g L-1 of photocatalyst, and 2 h of reaction.
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Le, Tuan. "Développement de nouveaux photocatalyseurs à base de tétrazines et d'heptazines." Thesis, université Paris-Saclay, 2021. http://www.theses.fr/2021UPASF009.

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L’application de la photocatalyse en synthèse organique a connu un grand essor depuis une décennie. Cependant, la majorité des photocatalyseurs actuellement utilisés sont des composés organométalliques qui, malgré une efficacité remarquable, sont toxiques et couteux. Les travaux présentés dans ce manuscrit s’inscrivent dans le cadre d’un effort qui s’intensifie au cours de ces dernières années afin de trouver de nouvelles plateformes de catalyse photorédox efficaces et sans métaux. Deux familles de composés aromatiques azotés y ont été étudiées : les s-tétrazines et les heptazines. Ce sont des molécules fluorescentes qui sont réduites de manière réversible à un haut potentiel de réduction à l’état excité.Les études sur les s-tétrazines, que ce soit sur leur synthèse, leurs propriétés physicochimiques, ou encore leur relation structure-activité, sont assez complètes. Toutefois, celles sur les heptazines ne le sont pas, du fait de la synthèse assez délicate de leur précurseur principal.La première partie de ce manuscrit est donc consacrée aux s-tétrazines. En particulier, leurs capacités photooxydantes ont été évaluées dans plusieurs modèles réactionnels qui étaient jusqu’alors réservés aux composés organométalliques.La deuxième partie concerne les heptazines et commence par la mise en place d’une nouvelle voie de synthèse efficace et moins dangereuse. On a procèdé à la synthèse de différentes heptazines, suivie d’une évalution systématique de leurspropriétés physicochimiques. Quelques réactions photorédox ont été effectuées en présence d’heptazines afin d’avoir un aperçu préliminaire global sur leur activité photorédox
The application of photocatalysis in organic synthesis has known a great growth over the past decade. However, the majority of photocatalysts currently used are organometallic compounds which, despite remarkable efficiencies, are toxic andexpensive. The work presented in this manuscript is a part of an effort that has intensified in recent years to find new efficient, metal-free photoredox catalysis platforms. Two families of nitrogenous aromatic compounds were studied there : The s-tetrazines and the heptazines. They are fluorescent molecules which are reversibly reduced at a high reduction potential in the excited state.While the studies on s-tetrazines, whether on their synthesis, their physicochemical properties, or their structure-activity relationship are quite complete, those on heptazines are not. And this is likely because of rather delicate and dangerous overall synthesis procedures.The first part of this manuscript is therefore devoted to s -tetrazines. In particular, their photooxidizing capacity has been evaluated using several reaction models which had been so far been used for organometallic compounds.The second part concerns the heptazines and begins with the establishment of a new efficient and less dangerous synthetic route. Different heptazines have been synthesized, and followed by a systematic evaluation of their physicochemicalproperties. A few photoredox reactions have been carried out in the presence of heptazines in order to gain an overview of their photoredox activity
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Lee, Soo-Keun. "Laser photocatalysts." Thesis, Robert Gordon University, 2001. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.344019.

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Ahmad, Ayla. "Synthesis and Evaluation of Photocatalytic Properties of BiOBr for Wastewater Treatment Applications." Thèse, Université d'Ottawa / University of Ottawa, 2013. http://hdl.handle.net/10393/30301.

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Visible light-driven photocatalysis has shown considerable potential in the area of clean and renewable energy, as well as in wastewater treatment. This thesis describes the synthesis, characterization and applicability of a visible-light active photocatalyst, bismuth oxybromide (BiOBr). The photocatalytic activity of BiOBr was investigated through its preparation via hydrothermal and solvothermal synthesis routes under various conditions. Hydrothermal catalyst was prepared using non template based method while for solvothermal synthesis CTAB was used as a template. Parameters of temperature and time of thermal treatment were optimized for each synthesis method and overall tests for catalyst dosage and recyclability were performed. An overall optimal route leading to high photocatalytic performance was also proposed based on the obtained results. Studies were also conducted to examine the applicability of optimally synthesized BiOBr in drinking water applications by studying catalyst-mediated disinfection of E. coli and degradation of phenol. Favourable results were obtained, confirming the prospective application of BiOBr as a viable photocatalyst for disinfection. Furthermore, the potential of enhancing BiOBr to further improve its performance is described through synthesis of a novel PdCl2/BiOBr based photocatalyst. Overall, the performance of BiOBr under various conditions in this study establishes its potential as a holistic photocatalyst and merits further development.
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Yamamoto, Akira. "Studies on Low-temperature De-NoX System over TiO2-based Photocatalysts." 京都大学 (Kyoto University), 2015. http://hdl.handle.net/2433/200501.

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Books on the topic "Photocatalysys"

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

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

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

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

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

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

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Naushad, Mu, Saravanan Rajendran, and Eric Lichtfouse, eds. Green Photocatalysts. Cham: Springer International Publishing, 2020. http://dx.doi.org/10.1007/978-3-030-15608-4.

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Yamashita, Hiromi, and Hexing Li, eds. Nanostructured Photocatalysts. Cham: Springer International Publishing, 2016. http://dx.doi.org/10.1007/978-3-319-26079-2.

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

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

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Book chapters on the topic "Photocatalysys"

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Kale, Bharat B., Manjiri A. Mahadadalkar, and 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.

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de Lasa, Hugo, Benito Serrano, and Miguel Salaices. "Photocatalysts, Radiation Sources and Auxiliary Equipment for Photocatalysis." In Photocatalytic Reaction Engineering, 49–62. Boston, MA: Springer US, 2005. http://dx.doi.org/10.1007/0-387-27591-6_3.

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Onishi, Taku. "Photocatalyst." In Quantum Computational Chemistry, 201–22. Singapore: Springer Singapore, 2017. http://dx.doi.org/10.1007/978-981-10-5933-9_12.

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Leonardo, Palmisano. "Photocatalyst." In Encyclopedia of Membranes, 1–2. Berlin, Heidelberg: Springer Berlin Heidelberg, 2012. http://dx.doi.org/10.1007/978-3-642-40872-4_461-2.

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Ohtani, Bunsho. "Photocatalyst." In Encyclopedia of Applied Electrochemistry, 1529–32. New York, NY: Springer New York, 2014. http://dx.doi.org/10.1007/978-1-4419-6996-5_497.

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Bhagat, B. R., and Alpa Dashora. "Photocatalyst." In Energy Conversion and Green Energy Storage, 3–28. Boca Raton: CRC Press, 2022. http://dx.doi.org/10.1201/9781003258209-2.

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Hajjaji, Anouar, Mosbah Amlouk, Mounir Gaidi, Brahim Bessais, and My Ali El Khakani. "TiO2 Photocatalysis." In Chromium Doped TiO2 Sputtered Thin Films, 75–84. Cham: Springer International Publishing, 2014. http://dx.doi.org/10.1007/978-3-319-13353-9_5.

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Shaham-Waldmann, Nurit, and Yaron Paz. "Modified Photocatalysts." In Photocatalysis and Water Purification, 103–43. Weinheim, Germany: Wiley-VCH Verlag GmbH & Co. KGaA, 2013. http://dx.doi.org/10.1002/9783527645404.ch5.

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Coote, Susannah C., and Thorsten Bach. "Enantioselective Photocatalysis." In Visible Light Photocatalysis in Organic Chemistry, 335–61. Weinheim, Germany: Wiley-VCH Verlag GmbH & Co. KGaA, 2018. http://dx.doi.org/10.1002/9783527674145.ch11.

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Teichner, S. J., and M. Formenti. "Heterogeneous Photocatalysis." In Photoelectrochemistry, Photocatalysis and Photoreactors, 457–89. Dordrecht: Springer Netherlands, 1985. http://dx.doi.org/10.1007/978-94-015-7725-0_19.

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Conference papers on the topic "Photocatalysys"

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Arakawa, Hironori, Zhigang Zou, Kazuhiro Sayama, and 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.

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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.
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Rasponi, Marco, Tania Ullah, Richard Gilbert, Gianfranco B. Fiore, and 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.

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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.
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Zhuo Luo, Shiying Zhang, Difa Xu, Yang You, and 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.

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

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Chen, Yen-Shin, Bo-Kai Chao, Tadaaki Nagao, and Chun-Hway Hsueh. "Improvement of Photocatalytic Efficiency by Adding Ag Nanoparticles and Reduced Graphene Oxide to TiO2." In JSAP-OSA Joint Symposia. Washington, D.C.: Optica Publishing Group, 2017. http://dx.doi.org/10.1364/jsap.2017.5p_a410_12.

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Titanium dioxide (TiO2) is the commonly used photocatalyst. However, because only a small ultraviolet portion of solar spectrum can excite the electron-hole pairs resulting from the large band gap (3.2 eV) [1] and the recombination rate is high, its efficiency is restrained. To overcome this drawback, we added silver nanoparticles and reduced graphene oxide (RGO) to construct the ternary plasmonic catalyst to improve the catalytic performance of TiO2 nanopowder (P25). We prepared three different geometries of Ag nanostructures including sphere, decahedron and prism because the plasmon resonance properties of Ag could be controlled by the morphology of Ag nanoparticle, which shows characteristic strong localized surface plasmon resonance (LSPR) leading to an increase in light absorption [2]. The incorporated RGO inhibited the charge recombination and enhanced the electron-hole separation. In this study, Ag nanodecahedrons/P25/RGO and Ag nano-prisms/P25/RGO hybrid photocatalysts possessed remarkable photocatalytic activity, which displayed over 8 times higher photocatalytic efficiency than the P25 photocatalyst.
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Li, Songtian, Yonghua Cheng, and Hang Gao. "Preparation, Characterization and Photocatalysis Properties of Visible Spectral Response Photocatalyst CoPcS/TiO2/K2Ti4O9." In 2010 International Conference on Challenges in Environmental Science and Computer Engineering. IEEE, 2010. http://dx.doi.org/10.1109/cesce.2010.190.

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Liu, Hong. "Infrared light active photocatalysts and its TiO2 nanobelt heterostructures: towards full spectrum of sunlight photocatalysis." In Nanophotonics, Nanoelectronics and Nanosensor. Washington, D.C.: OSA, 2013. http://dx.doi.org/10.1364/n3.2013.nsa2a.1.

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Mahmoud, Sawsan A., A. Abdel Aal, and Ahmed K. Aboul-Gheit. "Nanocrystalline ZnO Thin Film for Photocatalytic Purification of Water." In ASME 2008 2nd Multifunctional Nanocomposites and Nanomaterials International Conference. ASMEDC, 2008. http://dx.doi.org/10.1115/mn2008-47034.

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A thin film ZnO nanostructured catalyst exhibited a significantly greater superiority for the photodegradation of 2, 4, 6-TCP in water over photolysis via irradiation with UV of 254 nm wavelength. This ZnO photocatalyst was prepared via Zn metal evaporation and deposition on a glass sheet followed by calcination ature from 350 to 500 °C and the calcination time from 1 to 2h shows via SEM photography a decrease of ZnO nanoparticales sizes sheet followed by calcination (oxidation). Increasing the calcination temperature from 350 to 500 °C and the calcination time from 1 to 2h shows via SEM photography a decrease of ZnO nanoparticales sizes as well as the shape of their crystals finer needles, for which the crystallinity enhances as revealed by XRD. 2, 4, 6-Trichlorophenol was used as a model pollutant in water. Its photolysis using UV only or photocatalysis using UV irradiation in presence of the ZnO thin film catalyst indicated aromatic intermediates, which suffered of Cl by OH, addition of OH in a bare carbon in the aromatic ring, whereas in Photocatalysis deeper oxidation products, e.g., quinones and hydroquinones were also formed.
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Shouman, Mahmoud A., Ahmed H. El-Shazly, Mohamed S. Salem, Mohamed R. Elmarghany, Essam M. Abo-Zahhad, Marwa F. Elkady, Mohamed Nabil Sabry, and Ali Radwan. "A Hepatic Sinusoids-Based Microreactor for Photocatalytic Degradation of Methylene Blue by Titanium Dioxide." In ASME 2020 18th International Conference on Nanochannels, Microchannels, and Minichannels collocated with the ASME 2020 Heat Transfer Summer Conference and the ASME 2020 Fluids Engineering Division Summer Meeting. American Society of Mechanical Engineers, 2020. http://dx.doi.org/10.1115/icnmm2020-1004.

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Abstract Microreactor technology is considered a state of art technology that gained great attention from researchers due to the high effectiveness and the small residence time compared with other regular reactors. Great research work has been established to involve microreators in a variety of applications, including fuel production, food and chemical industries, medical applications. In the present study, a hepatic sinusoids-based microreactor is experimentally tested in Methylene blue degradation using titanium dioxide (TiO2) photocatalyst activated with ultraviolet lamp of wavelength 365 nm. Purification of water using photocatalysis is considered a promising technology that attract the industrial community. Different operating conditions are investigated including; flow rate, Methylene blue concentration, and TiO2 concentration. 3 different dye concentrations are used (10 ppm, 20 ppm, and 30 ppm) with 3 different photocatalyst concentrations (100 ppm, 300 ppm, and 500 ppm). The flow rate has a span from 0.25 ml/min to 1 ml/min. Experiments are conducted to determine best operating conditions. Results show that the microreactor system can be effectively used in dye degradation with a very small residence time. A degradation of over 95% was reached at a TiO2 concentration of 300 ppm and a flow rate of 0.25 ml/min for all tested dye concentrations.
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Lepeytre, C., C. Lavaud, and 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.

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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.
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Reports on the topic "Photocatalysys"

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

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Day, Nicholas. Polymeric Porphyrins as Solar Photocatalysts. Portland State University Library, January 2000. http://dx.doi.org/10.15760/etd.2621.

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D. Brent MacQueen. Discovery of Photocatalysts for Hydrogen Production. Office of Scientific and Technical Information (OSTI), October 2006. http://dx.doi.org/10.2172/908153.

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

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

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

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Majumder, S., M. Prairie, J. Shelnutt, and S. Khan. Engineered photocatalysts for detoxification of waste water. Office of Scientific and Technical Information (OSTI), December 1996. http://dx.doi.org/10.2172/420402.

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

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

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Shelnutt, John A., Zhongchun Wang, and Craig J. Medforth. Growth of metal and semiconductor nanostructures using localized photocatalysts. Office of Scientific and Technical Information (OSTI), March 2006. http://dx.doi.org/10.2172/919279.

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