Статті в журналах: "Photocatalytic organic"

1

López-Magano, Alberto, Alicia Jiménez-Almarza, Jose Alemán, and Rubén Mas-Ballesté. "Metal–Organic Frameworks (MOFs) and Covalent Organic Frameworks (COFs) Applied to Photocatalytic Organic Transformations." Catalysts 10, no. 7 (June 27, 2020): 720. http://dx.doi.org/10.3390/catal10070720.

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Among the different alternatives for catalysis using metal–organic frameworks (MOFs) or covalent organic frameworks (COFs), photocatalysis has remarkably evolved during the last decade. Photocatalytic reticular materials allowed recyclability and easy separation of catalyst from the product, also reaching the activity and selectivity commonly observed for molecular systems. Recently, photocatalytic MOFs and COFs have been applied to synthetic applications in order to obtain organic molecules of different complexity. However, although a good number of works have been devoted to this issue, an updated comprehensive revision on this field is still needed. The aim of this review was to fill this gap covering the following three general aspects: (1) common strategies on the design of reticular photocatalytic materials, (2) a comprehensive discussion of the photocatalytic organic reactions achieved by the use of COFs and MOFs, and (3) some critical considerations highlighting directions that should be considered in order to make advances in the study of photocatalytic COFs and MOFs.

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2

Xu, Jie. "Metal-Organic Frameworks for Photocatalytic Degradation of Organic Wastewater." Highlights in Science, Engineering and Technology 6 (July 27, 2022): 1–8. http://dx.doi.org/10.54097/hset.v6i.927.

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Environmental problems, including garbage disposal, land desertification, water pollution, and sand disaster, especially water pollution, should be faced seriously by human beings. Photocatalysis technology has been increasingly playing a dominant role in treating organic wastewater. This paper will introduce the degradation of organic wastewater using metal-organic framework (MOF) materials photocatalytic technology. This paper will summarize the related articles and research results published by the previous generation. This paper will introduce the material characteristics of MOFs and the physical and chemical properties of the materials and then will present the advantages of MOF materials in the photocatalytic degradation of organic wastewater. The working principle of MOFs for photocatalytic degradation of organic wastewater and the method of making MOF materials will be introduced. At the end of the article, the results of previous research in this field in recent years will be presented.

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3

CHEN, CHUANSHENG, QUN FANG, SHIYI CAO, and YONGXIANG YAN. "PHOTOCATALYTIC PROPERTY AND PHOTOCATALYTIC MECHANISM OF TiO2/Fe2O3 HYBRIDS FOR DEGRADATION OF ORGANIC DYES." Surface Review and Letters 26, no. 05 (June 2019): 1850196. http://dx.doi.org/10.1142/s0218625x18501962.

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In order to consider the performance enhancement and feasibility of practical application, this research work discussed the effects of different ions on the photocatalytic activity of TiO2/Fe2O3 hybrids in detail, involving H[Formula: see text], OH−, NH[Formula: see text], and NO[Formula: see text]. The TiO2/Fe2O3 hybrids were prepared by organic electrolyte-assisted sol–gel method under UV irradiation, and their function mechanisms were analyzed. Experiment results show that the resultant TiO2/Fe2O3 hybrids possess excellent photocatalytic activity and photocatalytic stability for degradation of organics under acid condition (pH 2–8). Notably, the NO[Formula: see text] ions could accelerate degradation of rhodamine B and methyl orange, and the recyclability of TiO2/Fe2O3 hybrids can be greatly enhanced in the co-existence of NO[Formula: see text] and NH[Formula: see text]. Meanwhile, this symbiosis of NO[Formula: see text] and NH[Formula: see text] is proven able to buffer the solution pH in photocatalysis. Furthermore, the prominent photocatalytic activity of TiO2/Fe2O3 hybrids for organic pollutants was mainly attributed to the formation of hydroxyl radicals (OH). The synthetic products show great potential applications in purification of air or wastewater that contains ammonia-nitrogen molecules.

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4

Zhang, P., and L. Jian. "Ozone-enhanced photocatalytic degradation of natural organic matter in water." Water Supply 6, no. 3 (July 1, 2006): 53–61. http://dx.doi.org/10.2166/ws.2006.730.

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Ozone-enhanced photocatalytic degradation of macromolecular natural organic matter (NOM) in drinking water source was investigated. The influences of ozone dosage, retention time and bicarbonate concentration on the NOM degradation rate were studied. The change of molecular weight distribution of NOM caused by ozone-enhanced photocatalysis was analysed, as well as the degradation rate of NOM with different molecular weight (MW). It was shown that ozone-enhanced photocatalysis was much better for NOM degradation than sole ozonation or photocatalysis. Increase of both ozone dosage and retention time could effectively increase the TOC removal rate, while biodegradability could be improved solely by an increase in ozone dosage. The existence of bicarbonate significantly reduced the photocatalytic degradation rate of NOM; however, its impact was effectively offset by the addition of ozone into the photocatalytic process. Macromolecular NOM was transformed into smaller molecules, and the larger NOM was mineralized by ozone-enhanced photocatalysis much faster than the smaller NOM.

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5

Muthukumaran, Shobha, Lili Song, Bo Zhu, Darli Myat, Jin-Yuan Chen, Stephen Gray, and Mikel Duke. "UV/TiO2 photocatalytic oxidation of recalcitrant organic matter: effect of salinity and pH." Water Science and Technology 70, no. 3 (May 27, 2014): 437–43. http://dx.doi.org/10.2166/wst.2014.221.

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Photocatalytic oxidation processes have interest for water treatment since these processes can remove recalcitrant organic compounds and operate at mild conditions of temperature and pressure. However, performance under saline conditions present in many water resources is not well known. This study aims to explore the basic effects of photocatalysis on the removal of organic matter in the presence of salt. A laboratory-scale photocatalytic reactor system, employing ultraviolet (UV)/titanium dioxide (TiO2) photocatalysis was evaluated for its ability to remove the humic acid (HA) from saline water. The particle size and zeta potential of TiO2 under different conditions including solution pH and sodium chloride (NaCl) concentrations were characterized. The overall degradation of organics over the NaCl concentration range of 500–2,000 mg/L was found to be 80% of the non-saline equivalent after 180 min of the treatment. The results demonstrated that the adsorption of HA onto the TiO2 particles was dependent on both the pH and salinity due to electrostatic interaction and highly unstable agglomerated dispersion. This result supports UV/TiO2 as a viable means to remove organic compounds, but the presence of salt in waters to be treated will influence the performance of the photocatalytic oxidation process.

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6

Du, Zhehua. "Research progress of MOF/Bismuth-based semiconductor composites in photocatalytic technology." E3S Web of Conferences 385 (2023): 04034. http://dx.doi.org/10.1051/e3sconf/202338504034.

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Photocatalysis has significant potential for environmental remediation and energy conversion, with a focus on designing and developing highly efficient photocatalysts. Composite materials consisting of bismuth-based semiconductors and metal-organic frameworks (MOFs) exhibit outstanding photocatalytic activity, and have garnered significant attention from researchers as a highly sought-after material. A review is conducted on recent advances in MOF/bismuth-based semiconductor composites. On this basis, the synthesis methods of MBCs are described in detail, and then the applications of MBCs in organic pollutant degradation, Cr (VI) reduction, water (H2O) splitting, nitrogen (N2) fixation discussed. Finally, this paper highlights the current challenges in photocatalysis using MBCs and provides insights into the future development direction for MBCs photocatalysis technology. The preparation and modification methods of MBCs, the improvement of photocatalytic efficiency, the mechanism of oxidative degradation of organic matter and the mechanism of photocatalytic complete hydrolysis of water need further study.

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7

Aslam, Mohammad, Dawood Bin Fazal, Faizan Ahmad, Abdullah Bin Fazal, Ahmad Zuhairi Abdullah, Mukhtar Ahmed, Mohammad Qamar, and Mohd Rafatullah. "Photocatalytic Degradation of Recalcitrant Pollutants of Greywater." Catalysts 12, no. 5 (May 18, 2022): 557. http://dx.doi.org/10.3390/catal12050557.

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These days, many countries have a water shortage and have limited access to clean water. To overcome this, a new treatment is emerging, namely, the photocatalytic processing of greywater. Photocatalytic processes to remove the organic matter from different greywater sources are critically reviewed. Their efficiency in degrading the organic matter in greywater is scrutinized along with factors that can affect the activity of photocatalysts. Modified TiO2, ZnO and TiO2 catalysts show great potential in degrading organic materials that are present in greywater. There are several methods that can be used to modify TiO2 by using sol-gel, microwave and ultrasonication. Overall, the photocatalytic approach alone is not efficient in mineralizing the organic compounds, but it works well when the photocatalysis is combined with oxidants and Fe3+. However, factors such as pH, concentration and catalyst-loading of organic compounds can significantly affect photocatalytic efficiency.

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8

Escobedo, Salvador, and Hugo de Lasa. "Photocatalysis for Air Treatment Processes: Current Technologies and Future Applications for the Removal of Organic Pollutants and Viruses." Catalysts 10, no. 9 (August 24, 2020): 966. http://dx.doi.org/10.3390/catal10090966.

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Photocatalysis for air treatment or photocatalytic oxidation (PCO) is a relatively new technology which requires titanium dioxide (TiO2) and a source of light (Visible or near-UV) to degrade pollutants contained in air streams. Present approaches for the photodegradation of indoor pollutants in air streams aim to eliminate volatile organic compounds (VOCs) and viruses, which are both toxic and harmful to human health. Photocatalysis for air treatment is an inexpensive and innovative green process. Additionally, it is a technology with a reduced environmental footprint when compared to other conventional air treatments which demand significant energy, require the disposal of used materials, and release CO2 and other greenhouse gases to the environment. This review discusses the most current and relevant information on photocatalysis for air treatment. This article also provides a critical review of (1) the most commonly used TiO2-based semiconductors, (2) the experimental syntheses and the various photocatalytic organic species degradation conversions, (3) the developed kinetics and computational fluid dynamics (CFD) and (4) the proposed Quantum Yields (QYs) and Photocatalytic Thermodynamic Efficiency Factors (PTEFs). Furthermore, this article contains important information on significant factors affecting the photocatalytic degradation of organic pollutants, such as reactor designs and type of photoreactor irradiation. Overall, this review describes state-of-the-art photocatalysis for air treatment to eliminate harmful indoor organic molecules, reviewing as well the potential applications for the inactivation of SARS-CoV2 (COVID-19) viruses.

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9

Yi, Yan, Siyu Wang, Hantang Zhang, Jie Liu, Xiuqiang Lu, Lang Jiang, Chengji Sui, Hai Fan, Shiyun Ai, and Jianwu Sun. "High mobility organic semiconductor for constructing high efficiency carbon nitride heterojunction photocatalysts." Journal of Materials Chemistry C 8, no. 48 (2020): 17157–61. http://dx.doi.org/10.1039/d0tc05123c.

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High-mobility organic semiconductor CuPc is used to construct CN/CuPc heterojunction photocatalysts, showing enhanced photocatalytic performances. This work proves the prospect of high-mobility organic semiconductors in photocatalysis.

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10

Santaclara, J. G., F. Kapteijn, J. Gascon, and M. A. van der Veen. "Understanding metal–organic frameworks for photocatalytic solar fuel production." CrystEngComm 19, no. 29 (2017): 4118–25. http://dx.doi.org/10.1039/c7ce00006e.

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The fascinating chemical and physical properties of MOFs have recently stimulated exploration of their application for photocatalysis. Design guidelines for these materials in photocatalytic solar fuel generation can be developed by applying the right spectroscopic tools.

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11

Khan, Mohammad Mansoob, Ashmalina Rahman, and Shaidatul Najihah Matussin. "Recent Progress of Metal-Organic Frameworks and Metal-Organic Frameworks-Based Heterostructures as Photocatalysts." Nanomaterials 12, no. 16 (August 17, 2022): 2820. http://dx.doi.org/10.3390/nano12162820.

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In the field of photocatalysis, metal-organic frameworks (MOFs) have drawn a lot of attention. MOFs have a number of advantages over conventional semiconductors, including high specific surface area, large number of active sites, and an easily tunable porous structure. In this perspective review, different synthesis methods used to prepare MOFs and MOFs-based heterostructures have been discussed. Apart from this, the application of MOFs and MOFs-based heterostructures as photocatalysts for photocatalytic degradation of different types of pollutants have been compiled. This paper also highlights the different strategies that have been developed to modify and regulate pristine MOFs for improved photocatalytic performance. The MOFs modifications may result in better visible light absorption, effective photo-generated charge carriers (e−/h+), separation and transfer as well as improved recyclability. Despite that, there are still many obstacles and challenges that need to be addressed. In order to meet the requirements of using MOFs and MOFs-based heterostructures in photocatalysis for low-cost practical applications, future development and prospects have also been discussed.

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12

Gowland, Dan C. A., Neil Robertson, and Efthalia Chatzisymeon. "Photocatalytic Oxidation of Natural Organic Matter in Water." Water 13, no. 3 (January 25, 2021): 288. http://dx.doi.org/10.3390/w13030288.

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Increased concentrations of natural organic matter (NOM), a complex mixture of organic substances found in most surface waters, have recently emerged as a substantial environmental issue. NOM has a significant variety of molecular and chemical properties, which in combination with its varying concentrations both geographically and seasonally, introduce the opportunity for an array of interactions with the environment. Due to an observable increase in amounts of NOM in water treatment supply sources, an improved effort to remove naturally-occurring organics from drinking water supplies, as well as from municipal wastewater effluents, is required to continue the development of highly efficient and versatile water treatment technologies. Photocatalysis has received increasing interest from around the world, especially during the last decade, as several investigated processes have been regularly reported to be amongst the best performing water treatment technologies to remove NOM from drinking water supplies and mitigate the formation of disinfection by products. Consequently, this overview highlights recent research and developments on the application of photocatalysis to degrade NOM by means of TiO2-based heterogeneous and homogeneous photocatalysts. Analytical techniques to quantify NOM in water and hybrid photocatalytic processes are also reviewed and discussed.

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13

Zhang, Ting, Guolong Xing, Weiben Chen, and Long Chen. "Porous organic polymers: a promising platform for efficient photocatalysis." Materials Chemistry Frontiers 4, no. 2 (2020): 332–53. http://dx.doi.org/10.1039/c9qm00633h.

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This review summarizes the latest advances of porous organic polymers (POPs) focusing on their applications in photocatalysis, including photocatalytic chemical transformations, photodetoxification of pollutants from water, and water splitting.

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14

Lin, Bo Tao, Dong Mei Shi, Tao Li, and Sen Kuan Meng. "Progress in Research of the Combined Adsorption-Photocatalysis for the Removal of Volatile Organic Compounds." Advanced Materials Research 1015 (August 2014): 540–43. http://dx.doi.org/10.4028/www.scientific.net/amr.1015.540.

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TiO2photocatalytic technology was developed in the past two decades in air treatment because of good photocatalytic effect, non-toxic, chemical stability, low cost, reusable features, the effect use of solar energy. A new composite materials of visible light photocatalytic degradation of low concentration of volatile organic compounds were produced by use of combining the adsorbent with TiO2photocatalytic technology.The adsorbent can enrich concentrations of volatile organic compounds on the surface of the TiO2photocatalyst. In this paper,the mechanism of the combined adsorption-photocatalysis for the removal of volatile organic compounds and immobilization methods、principle、craft were reviewed.The characteristic of the immobilization methods was analysed.It laid the foundation for the optimizing of the immobilization methods and the improving of the photocatalytic efficiency.

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Yu, Chengye, Mengxi Tan, Chengdong Tao, Yuxuan Hou, Chuanbao Liu, Huimin Meng, Yanjing Su, Lijie Qiao, and Yang Bai. "Remarkably enhanced piezo-photocatalytic performance in BaTiO3/CuO heterostructures for organic pollutant degradation." Journal of Advanced Ceramics 11, no. 3 (February 11, 2022): 414–26. http://dx.doi.org/10.1007/s40145-021-0544-4.

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AbstractIntroducing polarization field of piezoelectric materials is an effective strategy to improve photocatalytic performance. In this study, a new type of BaTiO3/CuO heterostructure catalyst was designed and synthesized to achieve high piezo-photocatalytic activity through the synergy of heterojunction and piezoelectric effect. The BaTiO3/CuO heterostructure shows a significantly enhanced piezo-photocatalytic degradation efficiency of organic pollutants compared with the individual BaTiO3 nanowires (NWs) and CuO nanoparticles (NPs). Under the co-excitation of ultrasonic vibration and ultraviolet radiation, the optimal degradation reaction rate constant k of polarized BaTiO3/CuO heterostructure on methyl orange (MO) dye can reach 0.05 min−1, which is 6.1 times of photocatalytic rate and 7 times of piezocatalytic rate. The BaTiO3/CuO heterostructure with remarkable piezo-photocatalytic behavior provides a promising strategy for the development of high-efficiency catalysts for wastewater purification, and it also helps understand the coupling mechanism between piezoelectric effect and photocatalysis.

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Wang, Kaihang, Jingyi Liu, Luwei Zhang, and Ning Wang. "Enhance the photocatalytic activity of fluoride graphdiyne/TiO₂ through introducing organic components." 2D Materials 10, no. 4 (August 24, 2023): 045014. http://dx.doi.org/10.1088/2053-1583/acf051.

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Abstract Structure engineering of hybrid materials has been proved to be an efficient method to screen out superior photocatalysis. The distribution and bonding environment of covalent linkage segments can be well regulated through structure decoration. Here, we propose a controlled strategy to optimize the photocatalytic performance of hybrid catalysts. Systematic adjusting of the performance can be achieved by introducing organic components into the carbon supporter. Under the guidance of this strategy, fluoride graphdiyne (FGDY) and phloroglucinol regulating FGDY (P-FGDY) is compounded with titanium dioxide (TiO2) under solvent thermal condition to obtain hybrid catalyst FGDY/TiO2 and P-FGDY/TiO2, respectively. Notably, the as-prepared P-FGDY/TiO2 exhibits superior enhancements towards photocatalytic degradation of rhodamine B, methylene blue, and levofloxacin under visible-light irradiation compared with FGDY/TiO2. These enhanced photocatalytic activities stem from the fact that the regulation of FGDY could further increase the photogenerated electron and hole separation efficiency of hybrid catalyst. This work provides a novel regulating pathway to optimize the photocatalytic activity of carbon-based hybrid photocatalysis material systems.

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Hu, Niannian, Youlie Cai, Lan Li, Xu-Sheng Wang, and Junkuo Gao. "Amino-Functionalized Titanium Based Metal-Organic Framework for Photocatalytic Hydrogen Production." Molecules 27, no. 13 (June 30, 2022): 4241. http://dx.doi.org/10.3390/molecules27134241.

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Photocatalytic hydrogen production using stable metal-organic frameworks (MOFs), especially the titanium-based MOFs (Ti-MOFs) as photocatalysts is one of the most promising solutions to solve the energy crisis. However, due to the high reactivity and harsh synthetic conditions, only a limited number of Ti-MOFs have been reported so far. Herein, we synthesized a new amino-functionalized Ti-MOFs, named NH2-ZSTU-2 (ZSTU stands for Zhejiang Sci-Tech University), for photocatalytic hydrogen production under visible light irradiation. The NH2-ZSTU-2 was synthesized by a facile solvothermal method, composed of 2,4,6-tri(4-carboxyphenylphenyl)-aniline (NH2-BTB) triangular linker and infinite Ti-oxo chains. The structure and photoelectrochemical properties of NH2-ZSTU-2 were fully studied by powder x-ray diffraction, scanning electron microscope, nitro sorption isotherms, solid-state diffuse reflectance absorption spectra, and Mott–Schottky measurements, etc., which conclude that NH2-ZSTU-2 was favorable for photocatalytic hydrogen production. Benefitting from those structural features, NH2-ZSTU-2 showed steady hydrogen production rate under visible light irradiation with average photocatalytic H2 yields of 431.45 μmol·g−1·h−1 with triethanolamine and Pt as sacrificial agent and cocatalyst, respectively, which is almost 2.5 times higher than that of its counterpart ZSTU-2. The stability and proposed photocatalysis mechanism were also discussed. This work paves the way to design Ti-MOFs for photocatalysis.

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Li, Ying, Hua Xu, Shuxin Ouyang, and Jinhua Ye. "Metal–organic frameworks for photocatalysis." Physical Chemistry Chemical Physics 18, no. 11 (2016): 7563–72. http://dx.doi.org/10.1039/c5cp05885f.

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Metal–organic frameworks (MOFs) have emerged as novel photocatalysts owing to their inherent structural characteristics of a large surface area and a well-ordered porous structure. In this article, we summarize various strategies carried out over MOFs via either modification of the organic linker/metal clusters or incorporation with metal/complex catalysts to enhance the light absorption, charge separation, reactant adsorption/activation of MOF-based photocatalysis towards the superior photocatalytic performance.

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19

Tsymbal, D. O. "Economic rationale for the use of photocatalysis for the determination of chemical oxygen demand of various types of waters." Health and Ecology Issues 20, no. 2 (July 10, 2023): 108–14. http://dx.doi.org/10.51523/2708-6011.2023-20-2-14.

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Objective. To evaluate the economic efficiency of the photocatalytic method of oxidation of organic substances in the framework of laboratory analysis.Materials and methods. Standard statistical methodsResults. The high economic feasibility of using photocatalysis to determine chemical oxygen demand (COD) has been demonstrated.Conclusion. The use of the photocatalytic method for determining COD seems economically justified and promising.

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Huertas, Rosa M., Maria C. Fraga, João G. Crespo, and Vanessa J. Pereira. "Solvent-Free Process for the Development of Photocatalytic Membranes." Molecules 24, no. 24 (December 6, 2019): 4481. http://dx.doi.org/10.3390/molecules24244481.

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This work described a new sustainable method for the fabrication of ceramic membranes with high photocatalytic activity, through a simple sol-gel route. The photocatalytic surfaces, prepared at low temperature and under solvent-free conditions, exhibited a narrow pore size distribution and homogeneity without cracks. These surfaces have shown a highly efficient and reproducible behavior for the degradation of methylene blue. Given their characterization results, the microfiltration photocatalytic membranes produced in this study using solvent-free conditions are expected to effectively retain microorganisms, such as bacteria and fungi that could then be inactivated by photocatalysis.

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Chen, Yanyan, Qi Hu, Minghui Yu, Xiaoyu Gong, Shenjie Li, Shuang Wang, Hao Yu, and Zhiqiang Li. "In situ construction of a direct Z-scheme CdIn2S4/TiO2 heterojunction for improving photocatalytic properties." CrystEngComm 23, no. 29 (2021): 5070–77. http://dx.doi.org/10.1039/d1ce00338k.

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Mansouri, L., L. Bousselmi, and A. Ghrabi. "Degradation of recalcitrant organic contaminants by solar photocatalysis." Water Science and Technology 55, no. 12 (June 1, 2007): 119–25. http://dx.doi.org/10.2166/wst.2007.397.

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Biological pre-treated landfill leachates of Djebel Chakir contains some macromolecular organic substances that are resistant to biological degradation. The aim of the present work is to assess the feasibility of removing refractory organic pollutants in biological pre-treated landfill leachate by solar photocatalyse process. Leachate pollutant contents are studied to assess their contribution to leachate pollution and their treatability by solar photocatalyse process. Phenol is chosen as model of pollutants, to evaluate its removal and the efficiency of the photocatalytic system. The experiments were carried out in suspended photocatalytic reactor, using TiO2 Degussa P25, under sunlight illumination (UV-A: 15–31 W/cm2). Under optimum operational conditions, applied to single reactant (phenol), the system presents a TOC removal of 90% (the degradation follows a first-order kinetic). Based on the TOC removal, the results shows that the degradation of biological pre-treated leachate follows a zero-order kinetic. After 5 h of sunlight exposure, 74% of COT is removed. The TOC removal is the best without any correction of the pH and at the TiO2 concentration of 2.5 g/L. The photocatalytic degradation of organic contaminants as well as the formation and disappearance of the by-products were followed by GC/MS. The solar photocatalysis processes induce several modifications of the matrix leading to more biodegradable forms: all the remaining and new compounds generated after the biological pre-treatment of leachate are degraded and other types of organics appear, mainly carboxylic acid, aliphatic hydrocarbons and phtalic acids.

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Yuan, Chung-Shin, Iau-Ren Ie, Ji-Ren Zheng, Chung-Hsuan Hung, Zu-Bei Lin, and Ching-Hsun Shih. "A Review of Electrical Assisted Photocatalytic Technologies for the Treatment of Multi-Phase Pollutants." Catalysts 11, no. 11 (October 31, 2021): 1332. http://dx.doi.org/10.3390/catal11111332.

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This article reviews the fundamental theories and reaction mechanisms of photocatalytic technologies with the assistance of electrical field for degrading multi-phase pollutants. Photo(electro)catalysis including photocatalytic oxidation (PCO) and photoelectrocatalytic oxidation (PECO) have been a potential technologies applied for the treatment of organic and inorganic compounds in the wastewaters and waste gases, which has been treated as a promising technique by using semiconductors as photo(electro)catalysts to convert light or electrical energy to chemical energy. Combining photocatalytic processes with electrical field is an option to effectively decompose organic and inorganic pollutants. Although photocatalytic oxidation techniques have been used to decompose multi-phase pollutants, developing efficient advanced oxidation technologies (AOTs) by combining photocatalysis with electrical potential is urgently demanded in the future. This article reviews the most recent progress and the advances in the field of photocatalytic technologies combined with external electrical field, including the characterization of nano-sized photo(electro)catalysts, the degradation of multi-phase pollutants, and the development of electrical assisted photocatalytic technologies for the potential application on the treatment of organic and inorganic compounds in the wastewaters and waste gases. Innovative oxidation techniques regarding photo(electro)catalytic reactions with and without oxidants are included in this review article.

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Chi, Fang Li, Guo Dong Zhou, Biao Song, Bin Yang, Yao Hui Lv, Song Lin Ran, and Chun Guang Li. "CoTiO₃ Nanoparticles as a Highly Active Heterogeneous Catalyst of Peroxymonosulfate for the Degradation of Organic Pollutants under Visible-Light Illumination." Journal of Nano Research 42 (July 2016): 73–79. http://dx.doi.org/10.4028/www.scientific.net/jnanor.42.73.

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Visible light responsive CoTiO3 nanoparticles with average diameter of 100 nm were successfully synthesized by sol-gel method and were firstly applied to catalytic activation of peroxymonosulfate (PMS) for degradation of organic pollutants (Rhodamine B (RhB)). Photocatalytic experiments illustrated that CoTiO3 nanoparticles reveal good photocatalytic activity and excellent ability to activate PMS, the synergistic effect of visible light photocatalysis and sulfate radical generated from activated PMS can degradate RhB efficiently. Besides, CoTiO3 nanoparticles maintain their high photocatalytic and activation efficiency after three times recycling.

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Wu, Chun Du, Zhi Hui Jiang, and Qing Jie Xie. "Numerical Simulation of Magnetic Field and Photocatalysis Coupling Swage Treatment Reactor." Advanced Materials Research 726-731 (August 2013): 1890–94. http://dx.doi.org/10.4028/www.scientific.net/amr.726-731.1890.

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A new reactor was designed. It based on magnetic field and photocatalytic technology which have the ability to improve the swage treatment effect. It was improved and optimized according to combining photocatalysis with the magnetic field that could strengthen photocatalysis process. The modified k-ε equation model was used to simulate the wastewater velocity in the reactor. Results show that in the reaction zone,the fluid appeared circulation and the turbulence intensity was strong,which had advantage of increasing the contact of photocatalytic materials and organic molecules for improving the magnetic field and photocatalysis coupling reactive efficiency.

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Bardadym, Yuliia, Serhii Kobylinskyi, Larisa Kobrina, and Serhii Riabov. "THE USE OF CYCLODEXTRINS TO INCREASE THE EFFICIENCY OF TITANIUM DIOXIDE IN THE HETEROGENEOUS CATALYSIS." Ukrainian Chemistry Journal 86, no. 7 (August 20, 2020): 32–52. http://dx.doi.org/10.33609/2708-129x.86.7.2020.32-52.

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Photocatalytic oxidation is a very young direction, but in the same time it is one of the most promising, safe and effective methods of removing organic pollutants (in particular dyes and microbial pathogens) from the aquatic environment. General information on titanium dioxide, cyclodextrin and its derivatives is presented in this literature review. The results of recent studies regarding the practical application of titanium dioxide and cyclodextrins for the treatment of wastewaters and purification them from organic pollutants of various nature by the methods of heterogeneous photocatalysis are given, the principles of their work as a photocatalytic system are discussed in detail. These compounds are of interest in terms of both scientific search and practical application due to their semiconductor properties, nontoxicity, chemical stability, high photocatalytic activity.

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27

McIntyre, Hannah M., and Megan L. Hart. "Photocatalytic Porous Silica-Based Granular Media for Organic Pollutant Degradation in Industrial Waste-Streams." Catalysts 11, no. 2 (February 15, 2021): 258. http://dx.doi.org/10.3390/catal11020258.

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Photocatalytic treatment of organic contaminants in industrial wastewaters has gained interest due to their potential for effective degradation. However, photocatalytic slurry reactors are hindered by solution turbidity, dissolved salt content, and absorbance of light. Research presented here introduces the development and application of a novel, photocatalytic, porous silica-based granular media (SGM). SGM retains the cross-linked structure developed during synthesis through a combination of foaming agent addition and activation temperature. The resultant media has a high porosity of 88%, with a specific surface area of ~150 m2/gram. Photocatalytic capabilities are further enhanced as the resultant structure fixes the photocatalyst within the translucent matrix. SGM is capable of photocatalysis combined with diffusion of nucleophiles, electrophiles, and salts from pore space. The photocatalytic efficiencies of SGM at various silica contents were quantified in batch reactors using methylene blue destruction over time and cycles. Methylene blue concentrations of 10 mg/L were effectively degraded (>90%) within 40 min. This effectiveness was retained over multiple cycles and various methylene blue concentrations. SGM is a passive and cost-effective granular treatment system technology which can translate to other organic contaminants and industrial processes.

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28

Mengjie, Wu, and Liu Kun. "Application of and research on TiO2 photocatalysis technology." E3S Web of Conferences 165 (2020): 05001. http://dx.doi.org/10.1051/e3sconf/202016505001.

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Nano-TiO2 photocatalysis technology is a new environmental pollutant purification technology, but its application is very extensive. This paper introduces the photocatalytic properties of nano-TiO2, and summarizes the research progress of nano-TiO2 in industrial wastewater, marine pollution, solid waste degradation, air purification and sterilization. At the same time, it is pointed out that the nano-TiO2 photocatalytic technology has not fully reached the practical application level, and the development trend of nano-TiO2 photocatalytic materials is prospected. Photocatalytic oxidation (PCO) using nanomaterials is a promising technology for removing pollutants, especially in deodorization, degradation of volatile organic compounds (VOCs) and sterilization. The mechanism of nanometer photocatalysis was reviewed in this paper. The influence factors including initial concentration of pollutants, reaction time, light intensity, humidity, surface area and catalyst activity were discussed. Furthermore, the application in photocatalytic removal of gas phase contaminants was summarized, and the future development of its application was proposed based on the existing problems.

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29

Le Pivert, Marie, Nathan Martin, and Yamin Leprince-Wang. "Hydrothermally Grown ZnO Nanostructures for Water Purification via Photocatalysis." Crystals 12, no. 3 (February 22, 2022): 308. http://dx.doi.org/10.3390/cryst12030308.

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Semiconductor-based photocatalysis is a well-known and efficient process for achieving water depollution with very limited rejects in the environment. Zinc oxide (ZnO), as a wide-bandgap metallic oxide, is an excellent photocatalyst, able to mineralize a large scale of organic pollutants in water, under UV irradiation, that can be enlarged to visible range by doping nontoxic elements such as Ag and Fe. With high surface/volume ratio, the ZnO nanostructures have been shown to be prominent photocatalyst candidates with enhanced photocatalytic efficiency, owing to their being low-cost, non-toxic, and able to be produced with easy and controllable synthesis. Thus, ZnO nanostructures-based photocatalysis can be considered as an eco-friendly and sustainable process. This paper presents the photocatalytic activity of ZnO nanostructures (NSs) grown on different substrates. The photocatalysis has been carried out both under classic mode and microfluidic mode. All tests show the notable photocatalytic efficiency of ZnO NSs with remarkable results obtained from a ZnO-NSs-integrated microfluidic reactor, which exhibited an important enhancement of photocatalytic activity by drastically reducing the photodegradation time. UV-visible spectrometry and high-performance liquid chromatography, coupled with mass spectrometry (HPLC-MS), are simultaneously used to follow real-time information, revealing both the photodegradation efficiency and the degradation mechanism of the organic dye methylene blue.

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30

Prihod'ko, Roman V., and Nely M. Soboleva. "Photocatalysis: Oxidative Processes in Water Treatment." Journal of Chemistry 2013 (2013): 1–8. http://dx.doi.org/10.1155/2013/168701.

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The efficiency of various homogeneous and heterogeneous systems photocatalytic processes destructive oxidation of organic compounds of different classes is considered. It is shown that photocatalytic methods can significantly increase the speed and depth (up to complete mineralization) of decomposition processes of toxicants. The use of photocatalysis (PC) in the creation of low-power water treatment technologies is a promising direction in addressing environmental problems of the hydrosphere.

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Ameta, Rakshit, Surbhi Benjamin, Aarti Ameta, and Suresh C. Ameta. "Photocatalytic Degradation of Organic Pollutants: A Review." Materials Science Forum 734 (December 2012): 247–72. http://dx.doi.org/10.4028/www.scientific.net/msf.734.247.

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Water pollution is increasing at an ever increasing pace and the whole world is in the cancerous grip of this pollution. Various industries are discharging their untreated effluents into the nearby water resources; thus, adding to the existing water pollution to a great extent. Hence, there is a pressing demand to develop an alternate technology for wastewater treatment and in this context; photocatalysis has emerged as an Advanced Oxidation Process with green chemical approach for such a treatment. This chapter deals with photocatalytic degradation of different kinds of organic pollutants; mainly surfactants, pesticides, dyes, phenols, chloro compounds, nitrogen containing compounds etc. Mechanisms of their degradation have also been discussed with hydroxyl and allied radicals as the main active oxidizing species.

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32

Feng, Jian, Xia Ran, Li Wang, Bo Xiao, Li Lei, Jinming Zhu, Zuoji Liu, et al. "The Synergistic Effect of Adsorption-Photocatalysis for Removal of Organic Pollutants on Mesoporous Cu2V2O7/Cu3V2O8/g-C3N4 Heterojunction." International Journal of Molecular Sciences 23, no. 22 (November 17, 2022): 14264. http://dx.doi.org/10.3390/ijms232214264.

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Cu2V2O7/Cu3V2O8/g-C3N4 heterojunctions (CVCs) were prepared successfully by the reheating synthesis method. The thermal etching process increased the specific surface area. The formation of heterojunctions enhanced the visible light absorption and improved the separation efficiency of photoinduced charge carriers. Therefore, CVCs exhibited superior adsorption capacity and photocatalytic performance in comparison with pristine g-C3N4 (CN). CVC-2 (containing 2 wt% of Cu2V2O7/Cu3V2O8) possessed the best synergistic removal efficiency for removal of dyes and antibiotics, in which 96.2% of methylene blue (MB), 97.3% of rhodamine B (RhB), 83.0% of ciprofloxacin (CIP), 86.0% of tetracycline (TC) and 80.5% of oxytetracycline (OTC) were eliminated by the adsorption and photocatalysis synergistic effect under visible light irradiation. The pseudo first order rate constants of MB and RhB photocatalytic degradation on CVC-2 were 3 times and 10 times that of pristine CN. For photocatalytic degradation of CIP, TC and OTC, it was 3.6, 1.8 and 6.1 times that of CN. DRS, XPS VB and ESR results suggested that CVCs had the characteristics of a Z-scheme photocatalytic system. This study provides a reliable reference for the treatment of real wastewater by the adsorption and photocatalysis synergistic process.

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33

Fawad Ahmad, Fawad Ahmad, Sana Nisar Sana Nisar, Maira Mehmood Maira Mehmood, and Zakiratullah Zakiratullah. "A Critical Review on the Photo Degradation of Diazinon, A Persistent Organic Pesticides." Journal of the chemical society of pakistan 44, no. 5 (2022): 506. http://dx.doi.org/10.52568/001120/jcsp/44.05.2022.

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Broad production, utilization, and scrapping of pesticides worldwide increase the health concern of humans and animals, due to their bio-persistent and bio-accumulating nature. Among the present treatment methods, metaloxide based photocatalysis is the emerging technology for pesticide removal in aqueous medium, and has gained the interest of many researchers in the past years due to its feasibility, cost efficiency and higher degradation rate. This review briefly discusses the mechanism of metaloxide based photocatalytic degradation, reaction kinetics of pesticides degradation, optimization of operational parameters to enhance the degradation process, and different modifications such as binary, ternary or metal/non-metal dopped metaloxide photocatalysts to improve the effectiveness of degradation has also been analyzed. The effect of operational parameters like effect of catalyst dosage, pH, initial pesticide concentration, UV/sunlight, and irradiation time on the photocatalytic degradation of pesticide has been reviewed. The comparison of various photocatalysts for the degradation of diazinon from aqueous medium is summarized. However additional research is required to achieve fast and maximum degradation to keep the environment safe.

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34

Wang, Dan-Yan, Yu-Yun Yin, Chuan-Wei Feng, Rukhsana, and Yong-Miao Shen. "Advances in Homogeneous Photocatalytic Organic Synthesis with Colloidal Quantum Dots." Catalysts 11, no. 2 (February 18, 2021): 275. http://dx.doi.org/10.3390/catal11020275.

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Colloidal semiconductor quantum dots (QDs) have been proven to be excellent photocatalysts due to their high photostability, large extinction coefficients, and tunable optoelectrical properties, and have attracted extensive attention by synthetic chemists. These excellent properties demonstrate its promise in the field of photocatalysis. In this review, we summarize the recent application of QDs as homogeneous catalysts in various photocatalytic organic reactions. These meaningful works in organic transformations show the unique catalytic activity of quantum dots, which are different from other semiconductors.

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35

Wang, Jing Han, Taher A. Gaber, Shiao-Wei Kuo та Ahmed F. M. EL-Mahdy. "π-Electron-Extended Triazine-Based Covalent Organic Framework as Photocatalyst for Organic Pollution Degradation and H2 Production from Water". Polymers 15, № 7 (28 березня 2023): 1685. http://dx.doi.org/10.3390/polym15071685.

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Herein, we report the efficient preparation of π-electron-extended triazine-based covalent organic framework (TFP-TPTPh COF) for photocatalysis and adsorption of the rhodamine B (RhB) dye molecule, as well as for photocatalytic hydrogen generation from water. The resultant TFP-TPTPh COF exhibited remarkable porosity, excellent crystallinity, high surface area of 724 m2 g−1, and massive thermal stability with a char yield of 63.41%. The TFP-TPTPh COF demonstrated an excellent removal efficiency of RhB from water in 60 min when used as an adsorbent, and its maximum adsorption capacity (Qm) of 480 mg g−1 is among the highest Qm values for porous polymers ever to be recorded. In addition, the TFP-TPTPh COF showed a remarkable photocatalytic degradation of RhB dye molecules with a reaction rate constant of 4.1 × 10−2 min−1 and an efficiency of 97.02% under ultraviolet–visible light irradiation. Furthermore, without additional co-catalysts, the TFP-TPTPh COF displayed an excellent photocatalytic capacity for reducing water to generate H2 with a hydrogen evolution rate (HER) of 2712 μmol g−1 h−1. This highly active COF-based photocatalyst appears to be a useful material for dye removal from water, as well as solar energy processing and conversion.

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36

Cao, Xianyang, Wei Chen, Ping Zhao, Yaoyao Yang, and Deng-Guang Yu. "Electrospun Porous Nanofibers: Pore−Forming Mechanisms and Applications for Photocatalytic Degradation of Organic Pollutants in Wastewater." Polymers 14, no. 19 (September 23, 2022): 3990. http://dx.doi.org/10.3390/polym14193990.

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Electrospun porous nanofibers have large specific surface areas and abundant active centers, which can effectively improve the properties of nanofibers. In the field of photocatalysis, electrospun porous nanofibers can increase the contact area of loaded photocatalytic particles with light, shorten the electron transfer path, and improve photocatalytic activity. In this paper, the main pore−forming mechanisms of electrospun porous nanofiber are summarized as breath figures, phase separation (vapor−induced phase separation, non−solvent−induced phase separation, and thermally induced phase separation) and post−processing (selective removal). Then, the application of electrospun porous nanofiber loading photocatalytic particles in the degradation of pollutants (such as organic, inorganic, and bacteria) in water is introduced, and its future development prospected. Although porous structures are beneficial in improving the photocatalytic performance of nanofibers, they reduce their mechanical properties. Therefore, strategies for improving the mechanical properties of electrospun porous nanofibers are also briefly discussed.

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37

Martini, Jéssica, Carla A. Orge, Joaquim L. Faria, M. Fernando R. Pereira, and O. Salomé G. P. Soares. "Catalytic Advanced Oxidation Processes for Sulfamethoxazole Degradation." Applied Sciences 9, no. 13 (June 29, 2019): 2652. http://dx.doi.org/10.3390/app9132652.

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The degradation of sulfamethoxazole (SMX) by several advanced oxidation processes (AOPs) is carried out in the presence of different catalysts. The catalysts used consisted of carbon nanotubes (CNT), titanium dioxide (TiO2), a composite of carbon nanotubes and titanium dioxide (TiO2/CNT), and iron supported on carbon nanotubes (Fe/CNT). SMX removal was evaluated by catalytic ozonation, photocatalysis, catalytic oxidation with hydrogen peroxide, and combinations of these processes. The evolution of the SMX concentration during reaction time, the mineralization degree, the toxicity of the treated solution, and the formation of organic intermediates and ions were monitored. Ozonation catalyzed by Fe/CNT and CNT and photocatalytic ozonation in the presence of CNT presented the fastest degradation of SMX, whereas photocatalytic ozonation with CNT showed the best results in terms of organic matter removal (92% of total organic carbon (TOC) depletion). Total mineralization of the solution and almost complete reduction of toxicity was only achieved in the photocatalytic ozonation with H2O2 and Fe/CNT catalysts. The compound 3-amino-5-methylisoxazole was one of the first intermediates formed during SMX degradation. p-Benzoquinone was only formed in photocatalysis. Oxalic and oxamic acids were also detected and in most of the catalytic processes they appeared in small amounts. Ion concentrations increased with the reaction time.

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38

Escobedo, Salvador, and Hugo de Lasa. "Synthesis and Performance of Photocatalysts for Photocatalytic Hydrogen Production: Future Perspectives." Catalysts 11, no. 12 (December 10, 2021): 1505. http://dx.doi.org/10.3390/catal11121505.

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Photocatalysis for “green” hydrogen production is a technology of increasing importance that has been studied using both TiO2–based and heterojunction composite-based semiconductors. Different irradiation sources and reactor units can be considered for the enhancement of photocatalysis. Current approaches also consider the use of electron/hole scavengers, organic species, such as ethanol, that are “available” in agricultural waste, in communities around the world. Alternatively, organic pollutants present in wastewaters can be used as organic scavengers, reducing health and environmental concerns for plants, animals, and humans. Thus, photocatalysis may help reduce the carbon footprint of energy production by generating H2, a friendly energy carrier, and by minimizing water contamination. This review discusses the most up-to-date and important information on photocatalysis for hydrogen production, providing a critical evaluation of: (1) The synthesis and characterization of semiconductor materials; (2) The design of photocatalytic reactors; (3) The reaction engineering of photocatalysis; (4) Photocatalysis energy efficiencies; and (5) The future opportunities for photocatalysis using artificial intelligence. Overall, this review describes the state-of-the-art of TiO2–based and heterojunction composite-based semiconductors that produce H2 from aqueous systems, demonstrating the viability of photocatalysis for “green” hydrogen production.

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Kerc, Aslihan, Miray Bekbolet, and Ahmet Mete Saatci. "Effect of partial oxidation by ozonation on the photocatalytic degradation of humic acids." International Journal of Photoenergy 5, no. 2 (2003): 75–80. http://dx.doi.org/10.1155/s1110662x03000163.

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In this study humic acids, which are known to be a heterogeneous group of organic macromolecules found in natural waters, were oxidized using ozonation and photocatalysis in a sequential system. Ozonation was employed for achieving partial oxidation of humic acids prior to photocatalytic oxidation. Degradation of humic acid was explained by using pseudo first order reaction rate model based on UV-vis measurements. An improvement was achieved in the photocatalytic degradation rates with respect to the degree of pre-oxidation by ozonation. Due to the surface oriented nature of photocatalysis, adsorption characteristics of partially oxidized humic acid samples onTiO2photocatalyst were evaluated by the application of the Freundlich adsorption model. The photocatalytic degradation rates did not correlate well with the dark adsorption characteristics of the pre-ozonated as well as untreated humic acid samples.

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40

Guo, Liping, Yingli Niu, Haitao Xu, Qingwei Li, Shumaila Razzaque, Qi Huang, Shangbin Jin, and Bien Tan. "Engineering heteroatoms with atomic precision in donor–acceptor covalent triazine frameworks to boost photocatalytic hydrogen production." Journal of Materials Chemistry A 6, no. 40 (2018): 19775–81. http://dx.doi.org/10.1039/c8ta07391k.

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Engineering heteroatoms that precisely positioned in covalent triazine frameworks (CTFs) can dramatically enhance the photocatalytic hydrogen evolution rate of CTFs and is thus an effective strategy to improve the photocatalysis performance for porous organic polymers (POPs).

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41

Gallegos-Alcaíno, Alejandra, Nathaly Robles-Araya, Camila Avalos, Alexander Alfonso-Alvarez, Carlos A. Rodríguez, Héctor Valdés, Norma A. Sánchez-Flores, et al. "Synthesis of BiOI/Mordenite Composites for Photocatalytic Treatment of Organic Pollutants Present in Agro-Industrial Wastewater." Nanomaterials 12, no. 7 (March 31, 2022): 1161. http://dx.doi.org/10.3390/nano12071161.

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Recently, bismuth oxyiodide (BiOI) is an attractive semiconductor to use in heterogeneous photocatalysis processes. Unfortunately, BiOI individually shows limited photocatalytic efficiency, instability, and a quick recombination of electron/holes. Considering the practical application of this semiconductor, some studies show that synthetic zeolites provide good support for this photocatalyst. This support material permits a better photocatalytic efficiency because it prevents the quick recombination of photogenerated pairs. However, the optimal conditions (time and temperature) to obtain composites (BiOI/ synthetic zeolite) with high photocatalytic efficiency using a coprecipitation-solvothermal growth method have not yet been reported. In this study, a response surface methodology (RSM) based on a central composite design (CCD) was applied to optimize the synthesis conditions of BiOI/mordenite composites. For this purpose, eleven BiOI/mordenite composites were synthesized using a combined coprecipitation-solvothermal method under different time and temperature conditions. The photocatalytic activities of the synthesized composites were evaluated after 20 min of photocatalytic oxidation of caffeic acid, a typical organic pollutant found in agro-industrial wastewater. Moreover, BiOI/mordenite composites with the highest and lowest photocatalytic activity were physically and chemically characterized using nitrogen adsorption isotherms, scanning electron microscopy (SEM), X-ray diffraction (XRD), Fourier transform infrared spectroscopy (FT-IR), and diffuse reflectance spectroscopy (DRS). The optimal synthesis conditions prove to be 187 °C and 9 h. In addition, the changes applied to the experimental conditions led to surface property modifications that influenced the photocatalytic degradation efficiency of the BiOI/mordenite composite toward caffeic acid photodegradation.

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42

Wang, Chong-Chen, Jian-Rong Li, Xiu-Liang Lv, Yan-Qiu Zhang, and Guangsheng Guo. "Photocatalytic organic pollutants degradation in metal–organic frameworks." Energy Environ. Sci. 7, no. 9 (2014): 2831–67. http://dx.doi.org/10.1039/c4ee01299b.

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43

SHIMAOKA, Kento, Shota KUWAHARA, Makoto YAMASHITA, and Kenji KATAYAMA. "Study on Photocatalytic Organic Reactions Using Photocatalytic Microreactors." Analytical Sciences 30, no. 5 (2014): 619–21. http://dx.doi.org/10.2116/analsci.30.619.

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TRINH, Dang Trung Tri, Duangdao CHANNEI, Willawan KHANITCHAIDECHA, and Auppatham NAKARUK. "Photocatalytic Degradation of Organic Contaminants by BiVO4/Graphene Oxide Nanocomposite." Walailak Journal of Science and Technology (WJST) 15, no. 11 (November 1, 2018): 787–92. http://dx.doi.org/10.48048/wjst.2018.5969.

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In the present work, a nanocomposite of bismuth vanadate (BiVO4) and Graphene oxide (GO) was synthesized successfully by using hydrothermal process. The properties of BiVO4/GO nanocomposite were examined by various techniques including X-ray diffraction (XRD) and transmission electron microscopy (TEM). The XRD data indicated that pure BiVO4 nanoparticles had a monoclinic structure. Similarly, BiVO4/GO nanocomposite had the same structure without the peak of GO due to the transmission from GO to reduced GO during hydrothermal process. TEM images revealed that BiVO4 particles were integrated effectively with the GO sheets. The photocatalysis performance was evaluated by the degradation of methylene blue (MB) in an aqueous under the irradiation of visible light. The result showed that BiVO4/GO nanocomposites had higher photocatalytic activity than pure BiVO4 nanoparticles. The explanation was that GO sheets enhanced the separation of electron–hole pairs and the adsorbent capacity leading to improved photocatalytic activity.

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45

Saeed, Muhammad, Renzon Daniel Cosme Pecho, Sandeep Panchal, Sadeq K. Alhag, Laila A. Al-Shuraym, Khalid M. Al Syaad, and Usman Hanif Bhutta. "Synthesis of Ag-OMS Catalyst for Sunlight-Assisted Photodegradation of Crystal Violet Dye." Water 15, no. 13 (July 6, 2023): 2480. http://dx.doi.org/10.3390/w15132480.

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Анотація:

The contamination of water with organic pollutants, such as dyes, has become a serious threat to the environment. Therefore, the development of a cost-effective, eco-friendly, proficient, and visible-light-driven catalyst for the treatment of organic dye-contaminated wastewater has been a burning issue recently. Photocatalysis is suggested as a potential treatment technique for the eradication of organic pollutants. The 1D tunnel-structured manganese oxide octahedral molecular sieve (OMS) is a suitable substance to be tested as a visible-light-driven photocatalyst for the degradation of organic contaminants. However, the fast recombination of photoinduced charges (h+/e−) limits its photocatalytic application. The development of heterojunctions between OMS and other metals, such as Ag, is a suitable technique for improving the photocatalytic performance of OMS. In this study, Ag-OMS with plasmon-enhanced photocatalytic activity is reported for the photodegradation of crystal violet dye. Manganese oxide OMS was prepared by an acidic precipitation method using potassium permanganate, manganese acetate, and nitric acid as precursor materials. Ag nanoparticles were deposited on OMS using leaf extracts of Calotropis gigantea. The deposition of Ag enhanced the photocatalytic performance of OMS from 68 to 95%. The effects of Ag contents, catalyst dosage, and concentration of crystal violet dye on catalytic performance were explored as well. Approximately 100, 95, and 75% photodegradation of 50, 100, and 150 mg/L crystal violet dye was observed in 90, 120, and 120 min in the presence of 10% Ag-OMS, respectively. Excellent photocatalytic performance, low dose utilization, and reusability proved that Ag-OMS might have practical environmental applications.

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Konstas, Panagiotis-Spyridon, Ioannis Konstantinou, Dimitrios Petrakis, and Triantafyllos Albanis. "Synthesis, Characterization of g-C3N4/SrTiO3 Heterojunctions and Photocatalytic Activity for Organic Pollutants Degradation." Catalysts 8, no. 11 (November 17, 2018): 554. http://dx.doi.org/10.3390/catal8110554.

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Perovskite-structure SrTiO3 (STO) and graphitic carbon nitride (g-C3N4, CN) have attracted considerable attention in photocatalytic technology due to their unique properties, but also suffer from some drawbacks. The development of composite photocatalysts that combine properties of the individual semiconductors with enhanced charge separation is the current major trend in the photocatalysis field. In this study, SrTiO3/g-C3N4 (CNSTO) composites with different ratios (10, 20, 30, 40 and 50% g-C3N4) were prepared with a sonication mixing method. The samples were characterized by X-ray diffraction (XRD), scanning electron microscopy (SEM), N2 porosimetry, Fourrier transform infra-red spectroscopy (FT-IR), UV-Vis diffuse reflectance (DRS) and dynamic light scattering (DLS). STO spherical particles were successfully loaded on the g-C3N4 planes forming heterojunction composite materials. The photocatalytic activity was tested against the degradation of methylene blue (MB) dye under simulated solar light (SSL) irradiation following first-order kinetics. The photocatalytic activity followed the trend: 20CNSTO > 30CNSTO > 40CNSTO > 50CNSTO ≈ 10CNSTO, in accordance with the amount of •OH radicals determined by fluorescence spectroscopy. A Z-scheme mechanism was proposed for the enhanced photocatalytic degradation of MB as evidenced by trapping experiments with scavengers. Finally, significant stability and reusability was exhibited, indicating that such composites are of potential interest for photocatalytic treatments under sunlight irradiation.

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Verma, Hemant Kumar, Mahak Vij, and K. K. Maurya. "Synthesis, Characterization and Sun Light-Driven Photocatalytic Activity of Zinc Oxide Nanostructures." Journal of Nanoscience and Nanotechnology 20, no. 6 (June 1, 2020): 3683–92. http://dx.doi.org/10.1166/jnn.2020.17679.

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Low-temperature growth of nanostructures with large yield is a basic requirement for fulfilling the demand of large-scale applications of nanomaterials. The synthesis of nanoscale materials has gained considerable attention due to their excellent properties also in photocatalysis. Catalyst and Dopant free, solar active ZnO nanostructures photocatalysts with vacancy richness were synthesized in large quantities (in grams) through the co-precipitation growth process using ZnNi2·6H2O as the zinc source at room temperature. This method has advantages such as low temperature with high yield (>8 grams per liter) at atmospheric pressure synthesis. The experimental results confirm that synthesized ZnO samples were crystallized into a wurtzite hexagonal structure. Under direct sunlight energy examined degradation of organic dye methylene blue (MB) for photocatalytic activity using ZnO nanostructures. The photocatalytic performance depends on the different defects as well as the specific surface area. After photocatalytic degradation of MB dye in 60 min under natural sunlight irradiation colorless matrix was observed. The repeatability assessments for reusability of ZnO nanostructures after photocatalytic activity was also studied and reported for degradation of organic MB dye.

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Hussien, Mai S. A., Abdelfatteh Bouzidi, Hisham S. M. Abd-Rabboh, Ibrahim S. Yahia, Heba Y. Zahran, Mohamed Sh Abdel-wahab, Walaa Alharbi, Nasser S. Awwad, and Medhat A. Ibrahim. "Fabrication and Characterization of Highly Efficient As-Synthesized WO3/Graphitic-C3N4 Nanocomposite for Photocatalytic Degradation of Organic Compounds." Materials 15, no. 7 (March 28, 2022): 2482. http://dx.doi.org/10.3390/ma15072482.

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The incorporation of tungsten trioxide (WO3) by various concentrations of graphitic carbon nitride (g-C3N4) was successfully studied. X-ray diffraction (XRD), Scanning Electron Microscope (SEM), and Diffused Reflectance UV-Vis techniques were applied to investigate morphological and microstructure analysis, diffused reflectance optical properties, and photocatalysis measurements of WO3/g-C3N4 photocatalyst composite organic compounds. The photocatalytic activity of incorporating WO3 into g-C3N4 composite organic compounds was evaluated by the photodegradation of both Methylene Blue (MB) dye and phenol under visible-light irradiation. Due to the high purity of the studied heterojunction composite series, no observed diffraction peaks appeared when incorporating WO3 into g-C3N4 composite organic compounds. The particle size of the prepared composite organic compound photocatalysts revealed no evident influence through the increase in WO3 atoms from the SEM characteristic. The direct and indirect bandgap were recorded for different mole ratios of WO3/g-C3N4, and indicated no apparent impact on bandgap energy with increasing WO3 content in the composite photocatalyst. The composite photocatalysts’ properties better understand their photocatalytic activity degradations. The pseudo-first-order reaction constants (K) can be calculated by examining the kinetic photocatalytic activity.

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Albero, Josep, Diego Mateo, and Hermenegildo García. "Graphene-Based Materials as Efficient Photocatalysts for Water Splitting." Molecules 24, no. 5 (March 5, 2019): 906. http://dx.doi.org/10.3390/molecules24050906.

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Photocatalysis has been proposed as one of the most promising approaches for solar fuel production. Among the photocatalysts studied for water splitting, graphene and related materials have recently emerged as attractive candidates due to their striking properties and sustainable production when obtained from biomass wastes. In most of the cases reported so far, graphene has been typically used as additive to enhance its photocatalytic activity of semiconductor materials as consequence of the improved charge separation and visible light harvesting. However, graphene-based materials have demonstrated also intrinsic photocatalytic activity towards solar fuels production, and more specifically for water splitting. The photocatalytic activity of graphene derives from defects generated during synthesis or their introduction through post-synthetic treatments. In this short review, we aim to summarize the most representative examples of graphene based photocatalysts and the different approaches carried out in order to improve the photocatalytic activity towards water splitting. It will be presented that the introduction of defects in the graphenic lattice as well as the incorporation of small amounts of metal or metal oxide nanoparticles on the graphene surface improve the photocatalytic activity of graphene. What is more, a simple one-step preparation method has demonstrated to provide crystal orientation to the nanoparticles strongly grafted on graphene resulting in remarkable photocatalytic properties. These two features, crystal orientation and strong grafting, have been identified as a general methodology to further enhance the photocatalytic activity in graphenebased materials for water splitting. Finally, future prospects in this filed will be also commented.

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Boufi, Sami, Soraa Bouattour, Ana Maria Ferraria, Luís Filipe Vieira Ferreira, Ana Maria Botelho do Rego, Mohamed M. Chehimi, and Manuel Rei Vilar. "Cotton fibres functionalized with plasmonic nanoparticles to promote the destruction of harmful molecules: an overview." Nanotechnology Reviews 8, no. 1 (December 31, 2019): 671–80. http://dx.doi.org/10.1515/ntrev-2019-0058.

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AbstractSelf-decontaminating cotton fabrics were designed, produced and characterized aiming at the decomposition of harmful molecules namely chemical warfare agents (CWAs) by photocatalysis under day light or indoor illumination. This was achieved through the creation of a hybrid organic-inorganic nanostructured textile composed of a thin layer of TiO2 nanoparticles (NPs) generated in situ and chemically immobilised on the cellulose chains of cotton fibres. TiO2 NPs were converted into anatase by a hydrothermal procedure at low temperature around 100°C. The fabrics covered with TiO2 nanoparticles were examined in terms of their chemical composition, morphology, crystallinity, ageing, robustness and photocatalytic properties. In the whole preparation of the photocatalytic fabrics, only environment-friendly solvents (water or alcohol) were used. One of the important achievements in this work was providing fabrics with suitable photocatalytic activity under visible light. This was reached through plasmonic photocatalysis by generating noble metal nanoparticles (Au, Ag) and/ or their halides (AgBr, AgCl) neighbouring or topping the TiO2 NPs in the fabrics. The kinetics of degradation of the different systems were analysed and proved that the resulting fabrics could efficiently decompose, under visible light, organic dyes and dimethyl methylphosphonate (DMMP), a CWA simulant.Graphical abstract

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