1
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Zhang X, Zhang R, Ren P, Zhou J, Li W, Yang X. Carbon dioxide radical anion mediated dehalogenation kinetics and mechanisms of halogenated alkanes. WATER RESEARCH 2024; 259:121799. [PMID: 38815336 DOI: 10.1016/j.watres.2024.121799] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/30/2024] [Revised: 04/08/2024] [Accepted: 05/17/2024] [Indexed: 06/01/2024]
Abstract
Carbon dioxide radical anion (CO2•-) recently becomes appreciated in halogenated contaminants elimination; nevertheless, its application has been restricted by insufficient mechanistic understanding. Herein, we provided a quantitative insight into the kinetics and mechanisms of CO2•- mediated dehalogenation of halogenated alkanes. A CO2•- dominated UV254/H2O2/HCOO- system has been successfully established and demonstrated for effective elimination of 7 kinds of halogenated alkanes (71.3 % to 100 % of removal). Using a laser flash photolysis technology, the second-order rate constants of CO2•- ( [Formula: see text] ) reacting with CCl4, CHCl3 and CH2Cl2 were firstly reported, to be 2.5 × 108, 6.2 × 107 and 5.8 × 106 M-1s-1, respectively. [Formula: see text] presented a significant negative correlation with the lowest unoccupied molecular orbital energy (ELUMO) of chlorinated alkanes, proving that the enhanced dehalogenation of CO2•- was attributed by direct electron transfer mechanism. A fitting model was developed accordingly for [Formula: see text] prediction. This study also demonstrated that the CO2•- mediated ARP effectively removed halogenated alkanes regardless of pH condition (6.0∼9.0) and bicarbonate concentrations. These findings are significant in advancing the scientific understanding of CO2•- mediated ARP. This reductive process a promising control strategy for halogenated contaminants, such as polyfluoroalkyl substances (PFAS) and halogenated pharmaceuticals.
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Affiliation(s)
- Xinran Zhang
- School of Environmental Science and Engineering, Guangdong Provincial Key Laboratory of Environmental Pollution Control and Remediation Technology, Sun Yat-sen University, Guangzhou 510275, PR China; Shenzhen Research Institute of Sun Yat-sen University, Shenzhen 518052, PR China; State Key Laboratory of Urban Water Resource and Environment, Harbin Institute of Technology, Harbin 150090, PR China
| | - Rui Zhang
- School of Environmental Science and Engineering, Guangdong Provincial Key Laboratory of Environmental Pollution Control and Remediation Technology, Sun Yat-sen University, Guangzhou 510275, PR China
| | - Pengfei Ren
- Guangzhou Municipal Engineering Design & Research Institute, Guangzhou 510060, PR China
| | - Jianhua Zhou
- Guangzhou Municipal Engineering Design & Research Institute, Guangzhou 510060, PR China
| | - Weiguang Li
- State Key Laboratory of Urban Water Resource and Environment, Harbin Institute of Technology, Harbin 150090, PR China.
| | - Xin Yang
- School of Environmental Science and Engineering, Guangdong Provincial Key Laboratory of Environmental Pollution Control and Remediation Technology, Sun Yat-sen University, Guangzhou 510275, PR China.
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2
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Xu Y, Yu S, Huang C, Xu Z. Enhanced photocatalytic removal of bromate in drinking water by Au/TiO 2 under ultraviolet light. RSC Adv 2024; 14:23011-23022. [PMID: 39040693 PMCID: PMC11261577 DOI: 10.1039/d4ra03453h] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/10/2024] [Accepted: 07/05/2024] [Indexed: 07/24/2024] Open
Abstract
The photo-reduction of bromate (BrO3 -) has attracted much attention due to the carcinogenesis and genotoxicity of BrO3 - in drinking water. In this study, a heterojunction photocatalyst was developed by depositing Au nanoparticles (NPs) onto P25 TiO2 NPs through a one-pot, solvent-thermal process. Due to the unique properties of Au, the Au NPs deposited on the TiO2 surface created a Schottky barrier between the metal and the semiconductor, leading to an effective separation of photo-generated charge carriers as the Au nanoparticles served as electron sinks. The Au/TiO2 photocatalyst demonstrated efficient reduction of BrO3 - under UV light illumination without the need for sacrificial agents. The effect of different Au loading of Au/TiO2 was systematically investigated for its influence on the generation of electrons and the reduction ability of BrO3 -. The results indicate that the 1% Au/TiO2 catalyst exhibited a higher concentration of localized electrons, rendering it more effective in BrO3 - removal. The photocatalytic efficiency for BrO3 - reduction decreased upon the addition of K2S2O8 as an electron quencher, suggesting that the primary factor in this photo-reduction process was the availability of electrons. These findings hold promise for the potential application of the Au/TiO2 catalyst in the removal of BrO3 - from drinking water through photo-reduction.
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Affiliation(s)
- Ying Xu
- State Key Laboratory of Pollution Control and Resource Reuse, College of Environmental Science and Engineering, Tongji University Shanghai 200092 P. R. China
- Shanghai Institute of Pollution Control and Ecological Security Shanghai 200092 P. R. China
| | - Shuili Yu
- State Key Laboratory of Pollution Control and Resource Reuse, College of Environmental Science and Engineering, Tongji University Shanghai 200092 P. R. China
- Shanghai Institute of Pollution Control and Ecological Security Shanghai 200092 P. R. China
| | - Cong Huang
- PowerChina Huadong Engineering Corporation Limited Hangzhou 311122 P. R. China
| | - Zheng Xu
- PowerChina Huadong Engineering Corporation Limited Hangzhou 311122 P. R. China
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3
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Wang W, Liu H, Guo Z, Hu Z, Wang K, Leng Y, Yuan C, Li Z, Ge X. Various Antibacterial Strategies Utilizing Titanium Dioxide Nanotubes Prepared via Electrochemical Anodization Biofabrication Method. Biomimetics (Basel) 2024; 9:408. [PMID: 39056849 PMCID: PMC11274689 DOI: 10.3390/biomimetics9070408] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/29/2024] [Revised: 06/17/2024] [Accepted: 06/19/2024] [Indexed: 07/28/2024] Open
Abstract
Currently, titanium and its alloys have emerged as the predominant metallic biomaterials for orthopedic implants. Nonetheless, the relatively high post-operative infection rate (2-5%) exacerbates patient discomfort and imposes significant economic costs on society. Hence, urgent measures are needed to enhance the antibacterial properties of titanium and titanium alloy implants. The titanium dioxide nanotube array (TNTA) is gaining increasing attention due to its topographical and photocatalytic antibacterial properties. Moreover, the pores within TNTA serve as excellent carriers for chemical ion doping and drug loading. The fabrication of TNTA on the surface of titanium and its alloys can be achieved through various methods. Studies have demonstrated that the electrochemical anodization method offers numerous significant advantages, such as simplicity, cost-effectiveness, and controllability. This review presents the development process of the electrochemical anodization method and its applications in synthesizing TNTA. Additionally, this article systematically discusses topographical, chemical, drug delivery, and combined antibacterial strategies. It is widely acknowledged that implants should possess a range of favorable biological characteristics. Clearly, addressing multiple needs with a single antibacterial strategy is challenging. Hence, this review proposes systematic research into combined antibacterial strategies to further mitigate post-operative infection risks and enhance implant success rates in the future.
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Affiliation(s)
- Wuzhi Wang
- Key Laboratory of Mechanism Theory and Equipment Design of Ministry of Education, School of Mechanical Engineering, Tianjin University, Tianjin 300354, China
| | - Hanpeng Liu
- Tianjin Key Laboratory of Composite and Functional Materials, School of Materials Science and Engineering, Tianjin University, Tianjin 300072, China
| | - Zilin Guo
- Key Laboratory of Mechanism Theory and Equipment Design of Ministry of Education, School of Mechanical Engineering, Tianjin University, Tianjin 300354, China
| | - Zijun Hu
- School of Mechanical Engineering, Hebei University of Technology, Tianjin 300401, China
| | - Kefeng Wang
- National Engineering Research Center for Biomaterials, Sichuan University, Chengdu 610064, China
| | - Yujia Leng
- School of Precision Instrument and Opto-Electronics Engineering, Tianjin University, Tianjin 300072, China
| | - Caideng Yuan
- School of Chemical Engineering and Technology, Tianjin University, Tianjin 300350, China
| | - Zhaoyang Li
- Tianjin Key Laboratory of Composite and Functional Materials, School of Materials Science and Engineering, Tianjin University, Tianjin 300072, China
| | - Xiang Ge
- Key Laboratory of Mechanism Theory and Equipment Design of Ministry of Education, School of Mechanical Engineering, Tianjin University, Tianjin 300354, China
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4
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Yun H, Gao Q, Yan Y, Yu Y, Zhang Y, Li C. Continuously Adjustable Thickness of Bi 2MoO 6 Nanosheets Enhances Photocatalytic Oxidation. ACS OMEGA 2024; 9:22459-22465. [PMID: 38799307 PMCID: PMC11112557 DOI: 10.1021/acsomega.4c02493] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 03/15/2024] [Revised: 04/16/2024] [Accepted: 04/30/2024] [Indexed: 05/29/2024]
Abstract
In this study, two-dimensional (2D) nanosheet photocatalysts of Bi2MoO6 with varying thicknesses were synthesized by adjusting the temperature during the hydrothermal reaction. The thinnest Bi2MoO6 nanosheet reached an approximate thickness of ∼4 nm, while the thickest nanosheet measured only ∼16 nm. The photocatalytic performance for Rhodamine B (RhB) degradation was found to be the most effective for the thinnest Bi2MoO6 nanosheet, displaying a degradation rate constant of 0.11 min-1. This rate was 2.5 times higher than that observed for the ∼16 nm thick Bi2MoO6 photocatalyst. The enhanced performance of the thinner two-dimensional nanostructure can be attributed to improved separation and migration of photogenerated charges. Additionally, the study identified hydroxyl radicals (•OH) and superoxide radicals (•O2-) as crucial oxidative species, contributing to the efficient mineralization of RhB dye. This work highlights the controllable synthesis of 2D materials with varying thicknesses and their specific applications in photocatalytic oxidation.
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Affiliation(s)
- Hongjuan Yun
- Xinjiang
Academy of Environmental Protection Science, Urumqi, Xinjiang 830011, China
- Xinjiang
Engineering Technology Research Center for Cleaner Production, Urumqi, Xinjiang 830011, China
| | - Qingguo Gao
- Xinjiang
Academy of Environmental Protection Science, Urumqi, Xinjiang 830011, China
- Xinjiang
Engineering Technology Research Center for Cleaner Production, Urumqi, Xinjiang 830011, China
| | - Yin Yan
- Xinjiang
Institute of Technology, Urumqi, Xinjiang 830023, China
| | - Yin Yu
- Xinjiang
Academy of Environmental Protection Science, Urumqi, Xinjiang 830011, China
- Xinjiang
Engineering Technology Research Center for Cleaner Production, Urumqi, Xinjiang 830011, China
| | - Yuanyuan Zhang
- Xinjiang
Academy of Environmental Protection Science, Urumqi, Xinjiang 830011, China
- Xinjiang
Engineering Technology Research Center for Cleaner Production, Urumqi, Xinjiang 830011, China
| | - Chun Li
- Xinjiang
Academy of Environmental Protection Science, Urumqi, Xinjiang 830011, China
- Xinjiang
Engineering Technology Research Center for Cleaner Production, Urumqi, Xinjiang 830011, China
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5
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Ao X, Zhang X, Sun W, Linden KG, Payne EM, Mao T, Li Z. What is the role of nitrate/nitrite in trace organic contaminants degradation and transformation during UV-based advanced oxidation processes? WATER RESEARCH 2024; 253:121259. [PMID: 38377923 DOI: 10.1016/j.watres.2024.121259] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/27/2023] [Revised: 02/01/2024] [Accepted: 02/03/2024] [Indexed: 02/22/2024]
Abstract
The effectiveness of UV-based advanced oxidation processes (UV-AOPs) in degrading trace organic contaminants (TrOCs) can be significantly influenced by the ubiquitous presence of nitrate (NO3-) and nitrite (NO2-) in water and wastewater. Indeed, NO3-/NO2- can play multiple roles of NO3-/NO2- in UV-AOPs, leading to complexities and conflicting results observed in existing research. They can inhibit the degradation of TrOCs by scavenging reactive species and/or competitively absorbing UV light. Conversely, they can also enhance the elimination of TrOCs by generating additional •OH and reactive nitrogen species (RNS). Furthermore, the presence of NO3-/NO2- during UV-AOP treatment can affect the transformation pathways of TrOCs, potentially resulting in the nitration/nitrosation of TrOCs. The resulting nitro(so)-products are generally more toxic than the parent TrOCs and may become precursors of nitrogenous disinfection byproducts (N-DBPs) upon chlorination. Particularly, since the impact of NO3-/NO2- in UV-AOPs is largely due to the generation of RNS from NO3-/NO2- including NO•, NO2•, and peroxynitrite (ONOO-/ONOOH), this review covers the generation, properties, and detection methods of these RNS. From kinetic, mechanistic, and toxicologic perspectives, future research needs are proposed to advance the understanding of how NO3-/NO2- can be exploited to improve the performance of UV-AOPs treating TrOCs. This critical review provides a comprehensive framework outlining the multifaceted impact of NO3-/NO2- in UV-AOPs, contributing insights for basic research and practical applications of UV-AOPs containing NO3-/NO2-.
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Affiliation(s)
- Xiuwei Ao
- School of Energy and Environmental Engineering, Beijing Key Laboratory of Resource-oriented Treatment of Industrial Pollutants, International Science and Technology Cooperation Base for Environmental and Energy Technology of MOST, University of Science and Technology Beijing, Beijing, 100083, China
| | - Xi Zhang
- School of Energy and Environmental Engineering, Beijing Key Laboratory of Resource-oriented Treatment of Industrial Pollutants, International Science and Technology Cooperation Base for Environmental and Energy Technology of MOST, University of Science and Technology Beijing, Beijing, 100083, China
| | - Wenjun Sun
- School of Environment, Tsinghua University, Beijing 100084, China; Research Institute for Environmental Innovation (Suzhou) Tsinghua, Suzhou, 215163, China.
| | - Karl G Linden
- Department of Civil, Environmental, and Architectural Engineering, University of Colorado Boulder, 4001 Discovery Drive, Boulder, CO 80303, United States.
| | - Emma M Payne
- Department of Civil, Environmental, and Architectural Engineering, University of Colorado Boulder, 4001 Discovery Drive, Boulder, CO 80303, United States
| | - Ted Mao
- Research Institute for Environmental Innovation (Suzhou) Tsinghua, Suzhou, 215163, China; MW Technologies, Inc., Ontario L8N1E, Canada
| | - Zifu Li
- School of Energy and Environmental Engineering, Beijing Key Laboratory of Resource-oriented Treatment of Industrial Pollutants, International Science and Technology Cooperation Base for Environmental and Energy Technology of MOST, University of Science and Technology Beijing, Beijing, 100083, China
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6
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Falara PP, Ibrahim I, Zourou A, Sygellou L, Sanchez DE, Romanos GE, Givalou L, Antoniadou M, Arfanis MK, Han C, Terrones M, Kordatos KV. Bi-functional photocatalytic heterostructures combining titania thin films with carbon quantum dots (C-QDs/TiO 2) for effective elimination of water pollutants. ENVIRONMENTAL SCIENCE AND POLLUTION RESEARCH INTERNATIONAL 2023; 30:124976-124991. [PMID: 37160858 PMCID: PMC10754734 DOI: 10.1007/s11356-023-27285-7] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/05/2022] [Accepted: 04/24/2023] [Indexed: 05/11/2023]
Abstract
In this study, carbon quantum dots (C-QDs), prepared via hydrothermal-microwave procedures, were successfully combined with nanostructured titania (TiO2). The photocatalytic oxidation/reduction activity of the C-QDs/TiO2 composite films was evaluated in the decomposition of organic-inorganic contaminants from aqueous solutions under UV illumination. Physicochemical characterizations were applied to investigate the crystal structure of the carbon quantum dots and the composites. It was found that the prepared C-QDs/TiO2 composites had great contribution to the photocatalytic reduction of hexavalent chromium (Cr+6) species and 4-Nitrophenol (PNP) as well as to the photocatalytic oxidation of methylene blue (MB) and Rhodamine B (RhB) dyes. The mechanism of the photocatalytic reaction was studied with trapping experiments, revealing that the electron (e-) radical species were powerfully supported for the photocatalytic reduction of Cr+6 and PNP and the holes (h+) are the main active species for the photocatalytic oxidation reactions.
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Affiliation(s)
- Pinelopi P Falara
- School of Chemical Engineering, National Technical University of Athens, 9 Iroon Polytechniou St., 15780 Zografou, Athens, Greece
- Institute of Nanoscience and Nanotechnology, National Center for Scientific Research "Demokritos", 15341 Agia Paraskevi, Athens, Greece
| | - Islam Ibrahim
- Institute of Nanoscience and Nanotechnology, National Center for Scientific Research "Demokritos", 15341 Agia Paraskevi, Athens, Greece
- Department of Chemistry, Faculty of Science, Al-Azhar University, Nasr City, Cairo, 11884, Egypt
| | - Adamantia Zourou
- School of Chemical Engineering, National Technical University of Athens, 9 Iroon Polytechniou St., 15780 Zografou, Athens, Greece
| | - Labrini Sygellou
- Foundation of Research and Technology Hellas, Institute of Chemical Engineering and High Temperature Chemical Processes (FORTH/ICE-HT), POB 1414, GR-26504, Patras, Greece
| | - David Emanuel Sanchez
- Department of Materials Science and Engineering and Center for 2-Dimensional and Layered Materials, The Pennsylvania State University, University Park, PA, 16802, USA
| | - George Em Romanos
- Institute of Nanoscience and Nanotechnology, National Center for Scientific Research "Demokritos", 15341 Agia Paraskevi, Athens, Greece
| | - Lida Givalou
- School of Chemical Engineering, National Technical University of Athens, 9 Iroon Polytechniou St., 15780 Zografou, Athens, Greece
- Institute of Nanoscience and Nanotechnology, National Center for Scientific Research "Demokritos", 15341 Agia Paraskevi, Athens, Greece
| | - Maria Antoniadou
- Institute of Nanoscience and Nanotechnology, National Center for Scientific Research "Demokritos", 15341 Agia Paraskevi, Athens, Greece
- Department of Chemical Engineering, University of Western Macedonia, ZEP, 50100, Kozani, Greece
| | - Michalis K Arfanis
- Institute of Nanoscience and Nanotechnology, National Center for Scientific Research "Demokritos", 15341 Agia Paraskevi, Athens, Greece
| | - Changseok Han
- Department of Environmental Engineering, INHA University, 100 Inha-ro, Michuhol-gu, Incheon, 22212, South Korea
- Program in Environmental & Polymer Engineering, Graduate School of INHA University, 100 Inha-ro, Michuhol-gu, Incheon, 22212, South Korea
| | - Mauricio Terrones
- Department of Materials Science and Engineering and Center for 2-Dimensional and Layered Materials, The Pennsylvania State University, University Park, PA, 16802, USA
- Department of Physics, The Pennsylvania State University, University Park, Pennsylvania, 16802, USA
- Department of Chemistry and Materials Research Institute, The Pennsylvania State University, University Park, PA, 16802, USA
| | - Konstantinos V Kordatos
- School of Chemical Engineering, National Technical University of Athens, 9 Iroon Polytechniou St., 15780 Zografou, Athens, Greece.
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Hajareh Haghighi F, Mercurio M, Cerra S, Salamone TA, Bianymotlagh R, Palocci C, Romano Spica V, Fratoddi I. Surface modification of TiO 2 nanoparticles with organic molecules and their biological applications. J Mater Chem B 2023; 11:2334-2366. [PMID: 36847384 DOI: 10.1039/d2tb02576k] [Citation(s) in RCA: 5] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 03/01/2023]
Abstract
In recent years, titanium(IV) dioxide nanoparticles (TiO2NPs) have shown promising potential in various biological applications such as antimicrobials, drug delivery, photodynamic therapy, biosensors, and tissue engineering. For employing TiO2NPs in these fields, their nanosurface must be coated or conjugated with organic and/or inorganic agents. This modification can improve their stability, photochemical properties, biocompatibility, and even surface area for further conjugation with other molecules such as drugs, targeting molecules, polymers, etc. This review describes the organic-based modification of TiO2NPs and their potential applications in the mentioned biological fields. In the first part of this review, around 75 recent publications (2017-2022) are mentioned on the common TiO2NP modifiers including organosilanes, polymers, small molecules, and hydrogels, which improve the photochemical features of TiO2NPs. In the second part of this review, we presented 149 recent papers (2020-2022) about the use of modified TiO2NPs in biological applications, in which specific bioactive modifiers are introduced in this part with their advantages. In this review, the following information is presented: (1) the common organic modifiers for TiO2NPs, (2) biologically important modifiers and their benefits, and (3) recent publications on biological studies on the modified TiO2NPs with their achievements. This review shows the paramount significance of the organic-based modification of TiO2NPs to enhance their biological effectiveness, paving the way toward the development of advanced TiO2-based nanomaterials in nanomedicine.
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Affiliation(s)
- Farid Hajareh Haghighi
- Department of Chemistry, Sapienza University of Rome, Piazzale Aldo Moro 5, 00185, Rome, Italy.
| | - Martina Mercurio
- Department of Chemistry, Sapienza University of Rome, Piazzale Aldo Moro 5, 00185, Rome, Italy.
| | - Sara Cerra
- Department of Chemistry, Sapienza University of Rome, Piazzale Aldo Moro 5, 00185, Rome, Italy.
| | | | - Roya Bianymotlagh
- Department of Chemistry, Sapienza University of Rome, Piazzale Aldo Moro 5, 00185, Rome, Italy.
| | - Cleofe Palocci
- Department of Chemistry, Sapienza University of Rome, Piazzale Aldo Moro 5, 00185, Rome, Italy. .,Research Center for Applied Sciences to the Safeguard of Environment and Cultural Heritage (CIABC), Sapienza University of Rome, Piazzale Aldo Moro 5, 00185 Rome, Italy
| | - Vincenzo Romano Spica
- Department of Movement, Health and Human Sciences, University of Rome Foro Italico, Piazza Lauro De Bosis, 15, 00135 Rome, Italy
| | - Ilaria Fratoddi
- Department of Chemistry, Sapienza University of Rome, Piazzale Aldo Moro 5, 00185, Rome, Italy.
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Yongheng D, Huayu Y, Jiang L, Qi S, Qianwen Y, Yuntao Z. Direct Z-scheme P-TiO 2/g-C 3N 4 heterojunction for the photocatalytic degradation of sulfa antibiotics. RSC Adv 2023; 13:5957-5969. [PMID: 36816086 PMCID: PMC9936601 DOI: 10.1039/d2ra07289k] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/16/2022] [Accepted: 01/17/2023] [Indexed: 02/19/2023] Open
Abstract
The construction of direct Z-scheme heterojunctions with high photocatalytic degradation ability is important for wastewater treatment, but there are still many unsolved challenges. In this article, we report the fabrication of a Z-scheme P-TiO2/g-C3N4 (CNPT-X) heterostructure by the calcination method. Under simulated sunlight, CNPT-X composites are found to show excellent degradation performance against sulfonamide antibiotics sulfadiazine (SD), sulfamethazine (SM2), sulfamonomethoxine (SMM), and sulfamethoxazole (SMZ). CNPT-3 (400 mg L-1) can be used to degrade four sulfa antibiotics within 90 min, with a degradation rate as high as 99%, which is higher than that for P-TiO2 and g-C3N4 alone. The internal electron transfer paths and mechanisms for the composites are revealed by ESR radical detection experiments, XPS energy spectrum shifts, valence band positions and active material quenching experiments. Furthermore, the degradation products are analyzed by GC-MS, and four possible degradation pathways for sulfonamide pollutants are proposed. This photocatalyst provides new insights into the fundamental aspects of the photocatalytic degradation mechanism for composite pollutants, as well as new ideas for practical environmental applications.
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Affiliation(s)
- Dai Yongheng
- College of Resources and Environmental Engineering, Guizhou University Guiyang 550025 Guizhou P. R. China
| | - Yuan Huayu
- College of Resources and Environmental Engineering, Guizhou University Guiyang 550025 Guizhou P. R. China
| | - Li Jiang
- College of Resources and Environmental Engineering, Guizhou University Guiyang 550025 Guizhou P. R. China .,Guizhou Karst Environmental Ecosystems Observation and Research Station, Ministry of Education Guiyang 550025 Guizhou P. R. China
| | - Su Qi
- College of Resources and Environmental Engineering, Guizhou University Guiyang 550025 Guizhou P. R. China
| | - Yi Qianwen
- College of Resources and Environmental Engineering, Guizhou University Guiyang 550025 Guizhou P. R. China
| | - Zhang Yuntao
- College of Resources and Environmental Engineering, Guizhou University Guiyang 550025 Guizhou P. R. China
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9
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Moustafa HM, Mahmoud MS, Nassar MM. Kinetic analysis of p-rGO/n-TiO 2 nanocomposite generated by hydrothermal technique for simultaneous photocatalytic water splitting and degradation of methylene blue dye. ENVIRONMENTAL SCIENCE AND POLLUTION RESEARCH INTERNATIONAL 2023; 30:18181-18198. [PMID: 36207630 DOI: 10.1007/s11356-022-23430-w] [Citation(s) in RCA: 3] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/07/2022] [Accepted: 09/29/2022] [Indexed: 06/16/2023]
Abstract
In this study, the nanocomposites of reduced graphene oxide/TiO2 (rGO/TiO2 with different percentages) have been synthesized using a modified Hummers' method followed by hydrothermal treatment. The morphology and bonding structure of the prepared samples have been characterized by Fourier-transform infrared spectroscopy (FTIR), transmission electron microscopy (TEM), scanning electron microscopy (SEM), X-ray diffractometry (XRD), and X-ray photoelectron spectroscopy (XPS). The photo-characteristic aspects of the prepared samples have been indicated by photoluminescence (PL) emission spectroscopy and ultraviolet-visible diffuse reflection spectroscopy (DRS). The photocatalytic performance of rGO/TiO2 demonstrated that it is an effective photocatalyst for methylene blue (MB) dye decomposition through illumination by a mercury lamp. Within 60 min of continuous irradiation, the nanocomposite-induced MB decomposition reached a rate of over 99%. Different MB concentrations and optimal percent loadings in catalysts have been investigated. Furthermore, the results showed that as the amount of catalyst increased, the decomposition of MB enhanced. Finally, the loading percentage of rGO with TiO2 has been studied, and an empirical equation relating the reaction rate constant until the mass of the photocatalyst and dye concentration has been proposed. The results showed that the prepared nanocomposites had good photocatalytic activity toward water splitting and photo-decomposition of MB.
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Affiliation(s)
- Hager M Moustafa
- Chemical Engineering Department, Minia University, El-Minia, 61516, Egypt
| | - Mohamed S Mahmoud
- Chemical Engineering Department, Minia University, El-Minia, 61516, Egypt.
- Department of Engineering, University of Technology and Applied Sciences, Suhar, 311, Sultanate of Oman.
| | - Mamdouh M Nassar
- Chemical Engineering Department, Minia University, El-Minia, 61516, Egypt
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10
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A comprehensive study of the reduction of nitrate on natural FeTiO3: Photocatalysis and DFT calculations. Sep Purif Technol 2022. [DOI: 10.1016/j.seppur.2022.122570] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
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11
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Ahouei MA, Syed TH, Bishop V, Halacoglu S, Wang H, Wei W. Ti3C2Tx MXene Framework Materials: Preparation, Properties and Applications in Energy and Environment. Catal Today 2022. [DOI: 10.1016/j.cattod.2022.11.001] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2022]
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12
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Efficient One-Pot Synthesis of TiO2/ZrO2/SiO2 Ternary Nanocomposites Using Prunus × Yedoensis Leaf Extract for Enhanced Photocatalytic Dye Degradation. OXIDATIVE MEDICINE AND CELLULAR LONGEVITY 2022; 2022:3088827. [PMID: 36120599 PMCID: PMC9481355 DOI: 10.1155/2022/3088827] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 05/28/2022] [Accepted: 08/18/2022] [Indexed: 11/17/2022]
Abstract
A simple, efficient, and ecofriendly method was employed to synthesize TiO2/ZrO2/SiO2 ternary nanocomposites using Prunus × yedoensis leaf extract (PYLE) that shows improved photocatalytic and antibacterial properties. The characterization of the obtained nanocomposites was done by X-ray powder diffraction (XRD), Fourier transform infrared spectroscopy (FTIR), Raman spectroscopy, field-emission scanning electron microscopy (FE-SEM), and energy-dispersive X-ray spectroscopic (EDS) analysis. The synthesized ternary nanocomposites with nanoscale pore diameters were investigated for the elimination of Reactive Red 120 (RR120) dye. The obtained results showed about 96.2% removal of RR120 dye from aqueous solution under sunlight irradiation. Furthermore, it shows promising antibacterial activity against Staphylococcus aureus and Escherichia coli. The improved photocatalytic and antibacterial activity of TiO2/ZrO2/SiO2 may bring unique insights into the production of ternary nanocomposites and their applications in the environment and biomedical field.
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13
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Photocatalytic Degradation of Magenta Effluent Using Magnetite Doped TiO2 in Solar Parabolic Trough Concentrator. Catalysts 2022. [DOI: 10.3390/catal12090986] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022] Open
Abstract
Due to population growth and industrial development consumption of non-renewable energy sources, and consequently pollution, has increased. In order to reduce energy utilisation and preserve the environment, developed and developing countries are increasingly trying to find solutions based on renewable energy sources. Cost-effective wastewater treatment methods using solar energy would significantly ensure effective water source utilisation, thereby contributing towards sustainable development goals. In this paper, special emphasis is given to the use of solar energy as the driving force of the process, as well as the use of highly active magnetic TiO2-based catalysts. Therefore, in this study, we investigated the possibility of photocatalytic degradation of aqueous magenta graphic dye using titanium dioxide as a catalyst and DSD model in order to achieve the best process optimisation. TiO2 was successfully coated with magnetic nanoparticles by one step process and characterized using different techniques (BET, SEM/EDS, FTIR, XRD). Based on DSD statistical method optimal reaction conditions were pH = 6.5; dye concentration 100 mg/L; TiO2–Fe3O4 0.6 g/L, at which the highest degree of magenta dye decolourisation was achieved (85%). Application of solar energy coupled with magnetic TiO2 catalyst which could be recovered and reused makes this approach a promising alternative in green wastewater treatment.
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Toro RG, Adel AM, de Caro T, Brunetti B, Al-Shemy MT, Caschera D. A Facile One-Pot Approach to the Fabrication of Nanocellulose-Titanium Dioxide Nanocomposites with Promising Photocatalytic and Antimicrobial Activity. MATERIALS (BASEL, SWITZERLAND) 2022; 15:ma15165789. [PMID: 36013927 PMCID: PMC9415876 DOI: 10.3390/ma15165789] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/27/2022] [Revised: 08/12/2022] [Accepted: 08/19/2022] [Indexed: 06/01/2023]
Abstract
The combination of cellulosic materials and metal oxide semiconductors can provide composites with superior functional properties compared to cellulose. By using nanocellulose derived from agricultural waste, we propose a one-pot and environmentally friendly approach to the synthesis of nanocellulose-TiO2 (NC-TiO2) nanocomposites with peculiar photocatalytic activity and antibacterial effects. The as-prepared NC-TiO2 composites were fully characterized by different techniques, such as X-ray diffraction (XRD), μ-Raman, Fourier transform infrared spectroscopy (FTIR), thermogravimetry analysis (TGA), scanning electron microscopy (SEM), transmission electron microscopy (TEM), and diffuse reflectance spectroscopy (DRS). The results showed that well crystalline anatase TiO2 nanoparticles of about 5-6 nm were obtained. The photocatalytic activity in particular was evaluated by using methyl orange (MO) solution as a target pollutant at different pH values. It was found that all the tested NC-TiO2 nanocomposites showed stable photocatalytic activity, even after consecutive photocatalytic runs. In addition, NCT nanocomposites with higher TiO2 content showed degradation efficiency of almost 99% towards MO after 180 min of UV illumination. Finally, NC-TiO2 nanocomposites also showed intriguing antimicrobial properties, demonstrating to be effective against Gram-positive (Staphylococcus aureus, Bacillus subtilis) with 20-25 mm of inhibition zone and Gram-negative bacteria (Escherichia coli, Pseudomonas aeuroginosa) with 21-24 mm of inhibition zone, and fungi (Candida albicans) with 9-10 mm of inhibition zone.
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Affiliation(s)
- Roberta G. Toro
- Institute for the Study of Nanostructured Materials, National Research Council, Via Salaria Km 29,300, Monterotondo Stazione, 00015 Rome, Italy
| | - Abeer M. Adel
- National Research Centre, Cellulose and Paper Department, 33El-Bohouth St. (Former El-Tahrir St.), Dokki, Giza P.O. Box 12622, Egypt
| | - Tilde de Caro
- Institute for the Study of Nanostructured Materials, National Research Council, Via Salaria Km 29,300, Monterotondo Stazione, 00015 Rome, Italy
| | - Bruno Brunetti
- Dipartimento di Chimica, Università degli Studi di Roma “La Sapienza” Institute for the Study of Nanostructured Materials, National Research Council c/o, Piazzale Aldo Moro 5, 00185 Rome, Italy
| | - Mona T. Al-Shemy
- National Research Centre, Cellulose and Paper Department, 33El-Bohouth St. (Former El-Tahrir St.), Dokki, Giza P.O. Box 12622, Egypt
| | - Daniela Caschera
- Institute for the Study of Nanostructured Materials, National Research Council, Via Salaria Km 29,300, Monterotondo Stazione, 00015 Rome, Italy
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15
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Low Metal Loading (Au, Ag, Pt, Pd) Photo-Catalysts Supported on TiO2 for Renewable Processes. MATERIALS 2022; 15:ma15082915. [PMID: 35454608 PMCID: PMC9031976 DOI: 10.3390/ma15082915] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 01/11/2022] [Revised: 03/21/2022] [Accepted: 04/13/2022] [Indexed: 11/16/2022]
Abstract
Photo-catalysts based on titanium dioxide, and modified with highly dispersed metallic nanoparticles of Au, Ag, Pd and Pt, either mono- or bi-metallic, have been analyzed by multiple characterization techniques, including XRD, XPS, SEM, EDX, UV-Vis and N2 adsorption/desorption. Mono-metallic photo-catalysts were prepared by wet impregnation, while bi-metallic photocatalysts were obtained via deposition-precipitation (DP). The relationship between the physico-chemical properties and the catalyst’s behavior for various photo-synthetic processes, such as carbon dioxide photo-reduction to liquid products and glucose photo-reforming to hydrogen have been investigated. Among the tested materials, the catalysts containing platinum alone (i.e., 0.1 mol% Pt/TiO2) or bi-metallic gold-containing materials (e.g., 1 wt% (AuxAgy)/TiO2 and 1 wt% (AuxPtz)/TiO2) showed the highest activity, presenting the best results in terms of productivity and conversion for both applications. The textural, structural and morphological properties of the different samples being very similar, the main parameters to improve performance were function of the metal as electron sink, together with optoelectronic properties. The high activity in both applications was related to the low band gap, that allows harvesting more energy from a polychromatic light source with respect to the bare TiO2. Overall, high selectivity and productivity were achieved with respect to most literature data.
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16
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Wang Z, Wang Y, Gomes RL, Gomes HI. Selenium (Se) recovery for technological applications from environmental matrices based on biotic and abiotic mechanisms. JOURNAL OF HAZARDOUS MATERIALS 2022; 427:128122. [PMID: 34979385 DOI: 10.1016/j.jhazmat.2021.128122] [Citation(s) in RCA: 6] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/30/2021] [Revised: 12/08/2021] [Accepted: 12/17/2021] [Indexed: 06/14/2023]
Abstract
Selenium (Se) is an essential element with application in manufacturing from food to medical industries. Water contamination by Se is of concern due to anthropogenic activities. Recently, Se remediation has received increasing attention. Hence, different types of remediation techniques are listed in this work, and their potential for Se recovery is evaluated. Sorption, co-precipitation, coagulation and precipitation are effective for low-cost Se removal. In photocatalytic, zero-valent iron and electrochemical systems, the above mechanisms occur with reduction as an immobilization and detoxification process. In combination with magnetic separation, the above techniques are promising for Se recovery. Biological Se oxyanions reduction has been widely recognized as a cost-effective method for Se remediation, simultaneously generating biosynthetic Se nanoparticles (BioSeNPs). Increasing the extracellular production of BioSeNPs and controlling their morphology will benefit its recovery. However, the mechanism of the microbial production of BioSeNPs is not well understood. Se containing products from both microbial reduction and abiotic methods need to be refined to obtain pure Se. Eco-friendly and cost-effective Se refinery methods need to be developed. Overall, this review offers insight into the necessity of shifting attention from Se remediation to Se recovery.
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Affiliation(s)
- Zhongli Wang
- Food Water Waste Research Group, Faculty of Engineering, University of Nottingham, University Park, Nottingham NG7 2RD, United Kingdom.
| | - Yanming Wang
- Sustainable Process Technologies Research Group, Faculty of Engineering, University of Nottingham, University Park, Nottingham NG7 2RD, United Kingdom
| | - Rachel L Gomes
- Food Water Waste Research Group, Faculty of Engineering, University of Nottingham, University Park, Nottingham NG7 2RD, United Kingdom
| | - Helena I Gomes
- Food Water Waste Research Group, Faculty of Engineering, University of Nottingham, University Park, Nottingham NG7 2RD, United Kingdom
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17
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Ti3C2/W18O49 hybrid membrane with visible-light-driven photocatalytic ability for selective dye separation. Sep Purif Technol 2022. [DOI: 10.1016/j.seppur.2021.120145] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/29/2022]
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18
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Zheng R, Li C, Huang K, Guan Y, Wang W, Wang L, Bian J, Meng X. In-situ synthesis of N-doped TiO2 onto Ti3C2 MXene with enhanced photocatalytic activity in selective reduction of nitrate to N2. Inorg Chem Front 2022. [DOI: 10.1039/d1qi01614h] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
Photocatalysis exhibited promises in the reduction of nitrates into harmless dinitrogen. Herein, the synthesis of N-doped TiO2/Ti3C2 at low calcination temperature using NH4Cl and Ti3C2 was reported for the first...
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19
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Comparison of two cationic chitosan-based flocculants prepared by photocatalysis and photoinitiation systems: Synthesis mechanism, structure and performance in water treatment. Sep Purif Technol 2021. [DOI: 10.1016/j.seppur.2021.119670] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022]
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20
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Inactivation of pathogens by visible light photocatalysis with nitrogen-doped TiO2 and tourmaline-nitrogen co-doped TiO2. Sep Purif Technol 2021. [DOI: 10.1016/j.seppur.2021.118979] [Citation(s) in RCA: 9] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/19/2023]
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21
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Oseghe EO, Idris AO, Feleni U, Mamba BB, Msagati TAM. A review on water treatment technologies for the management of oxoanions: prospects and challenges. ENVIRONMENTAL SCIENCE AND POLLUTION RESEARCH INTERNATIONAL 2021; 28:61979-61997. [PMID: 34561799 DOI: 10.1007/s11356-021-16302-2] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/12/2021] [Accepted: 08/29/2021] [Indexed: 06/13/2023]
Abstract
Oxoanions are a class of contaminants that are easily released into the aquatic systems either through natural or anthropogenic activities. Depending on their oxidation states, they are highly mobile, resulting in the contamination of underground water. Above the permissible level in groundwater, they pose as threats to mammals when the contaminated water is consumed. Some of the health challenges caused are cancer, neurological, cardiac, gastrointestinal, and skin disorders. Several treatment technologies have been adopted over the years for the management of these oxoanions present in the aquatic systems. However interesting these treatment technologies might be, they also have their limitations such as cost-effectiveness, the complexity of the process, and generation of secondary pollutants. This work focused on some of the water treatment technologies applied for the removal of oxoanions. Some of the advantages and disadvantages of these treatment technologies are also highlighted. Amongst all the treatment technologies, adsorption is the most applied method for the removal of oxoanions. However, photocatalysis has a higher prospect since it is non-selective and secondary pollutants are not generated after the treatment process. Also, photocatalysis can simultaneously reduce and oxidise oxoanions as well as organic pollutants respectively.
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Affiliation(s)
- Ekemena Oghenovoh Oseghe
- Institute for Nanotechnology and Water Sustainability, College of Science, Engineering and Technology, University of South Africa, Florida Campus, Johannesburg, 1709, South Africa.
| | - Azeez Olayiwola Idris
- Institute for Nanotechnology and Water Sustainability, College of Science, Engineering and Technology, University of South Africa, Florida Campus, Johannesburg, 1709, South Africa
| | - Usisipho Feleni
- Institute for Nanotechnology and Water Sustainability, College of Science, Engineering and Technology, University of South Africa, Florida Campus, Johannesburg, 1709, South Africa
| | - Bhekie Brilliance Mamba
- Institute for Nanotechnology and Water Sustainability, College of Science, Engineering and Technology, University of South Africa, Florida Campus, Johannesburg, 1709, South Africa
| | - Titus Alfred Makudali Msagati
- Institute for Nanotechnology and Water Sustainability, College of Science, Engineering and Technology, University of South Africa, Florida Campus, Johannesburg, 1709, South Africa
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22
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Manikandan V, Mahadik MA, Hwang IS, Chae WS, Ryu J, Jang JS. Visible-Light-Active CuO x -Loaded Mo-BiVO 4 Photocatalyst for Inactivation of Harmful Bacteria ( Escherichia coli and Staphylococcus aureus) and Degradation of Orange II Dye. ACS OMEGA 2021; 6:23901-23912. [PMID: 34568669 PMCID: PMC8459411 DOI: 10.1021/acsomega.1c02879] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/02/2021] [Indexed: 05/06/2023]
Abstract
In the present study, Mo-BiVO4-loaded and metal oxide (MO: Ag2Ox, CoOx, and CuOx)-loaded Mo-BiVO4 photocatalysts were synthesized using a wet impregnation method and applied for microbial inactivation (Escherichia coli and Staphylococcus aureus) and orange II dye degradation under visible-light (VL) conditions (λ ≥ 420 nm). The amount of MO cocatalysts loaded onto the surface of the Mo-BiVO4 photocatalysts was effectively controlled by varying their weight percentages (i.e., 1-3 wt %). Among the pure Mo-BiVO4, Ag2Ox-, CoOx-, and CuOx-loaded Mo-BiVO4 photocatalysts used in bacterial E. coli and S. aureus inactivation under VL irradiation, the 2 wt % CuOx-loaded Mo-BiVO4 photocatalyst showed the highest degradation efficiency of E. coli (97%) and S. aureus (99%). Additionally, the maximum orange II dye degradation efficiency (80.2%) was achieved over the CuOx (2 wt %)-loaded Mo-BiVO4 photocatalysts after 5 h of radiation. The bacterial inactivation results also suggested that the CuO x -loaded Mo-BiVO4 nanostructure has significantly improved antimicrobial ability as compared to CuOx/BiVO4. The enhancement of the inactivation performance of CuOx-loaded Mo-BiVO4 can be attributed to the synergistic effect of Mo doping and Cu2+ ions in CuOx, which further acted as an electron trap on the surface of Mo-BiVO4 and promoted fast transfer and separation of the photoelectron (e-)/hole (h+) pairs for growth of reactive oxygen species (ROS). Furthermore, during the bacterial inactivation process, the ROS can disrupt the plasma membrane and destroy metabolic pathways, leading to bacterial cell death. Therefore, we provide a novel idea for visible-light-activated photocatalytic antibacterial approach for future disinfection applications.
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Affiliation(s)
- Velu Manikandan
- Division
of Biotechnology, Brain Korea 21 Plus Program, Advanced Institute
of Environment and Bioscience, College of Environmental and Bioresource
Sciences, Jeonbuk National University, Iksan 54596, Republic of Korea
| | - Mahadeo A. Mahadik
- Division
of Biotechnology, Brain Korea 21 Plus Program, Advanced Institute
of Environment and Bioscience, College of Environmental and Bioresource
Sciences, Jeonbuk National University, Iksan 54596, Republic of Korea
| | - In Seon Hwang
- Division
of Biotechnology, Brain Korea 21 Plus Program, Advanced Institute
of Environment and Bioscience, College of Environmental and Bioresource
Sciences, Jeonbuk National University, Iksan 54596, Republic of Korea
| | - Weon-Sik Chae
- Analysis
Research Division, Daegu Center, Korea Basic
Science Institute, Daegu 41566, Republic of Korea
| | - Jungho Ryu
- Geologic
Environment Research Division, Korea Institute
of Geoscience and Mineral Resources (KIGAM), Daejeon 34132, Republic of Korea
| | - Jum Suk Jang
- Division
of Biotechnology, Brain Korea 21 Plus Program, Advanced Institute
of Environment and Bioscience, College of Environmental and Bioresource
Sciences, Jeonbuk National University, Iksan 54596, Republic of Korea
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23
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Xiao Q, Yu S. Reduction of bromate from drinking water by sulfite/ferric ion systems: Efficacy and mechanisms. JOURNAL OF HAZARDOUS MATERIALS 2021; 418:125940. [PMID: 34111754 DOI: 10.1016/j.jhazmat.2021.125940] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/21/2021] [Revised: 04/04/2021] [Accepted: 04/19/2021] [Indexed: 06/12/2023]
Abstract
In this work, we investigate radical-based chemical reduction systems for BrO3- reduction. Sulfite/ferric ions [S(IV)/Fe(III)] systems eliminated 85% of 0.1 mM BrO3- in 1 min at pHini. 7.0, and 2.2 mg/L dissolved oxygen (DO) with rate constants (2.104 ± 0.090 min-1) orders of magnitude faster than previously published advanced reduction processes. Increasing S(IV) and Fe(III) concentrations and decreasing DO and pH contributed to faster BrO3- reduction likely due to enhanced reactive species. Lower anionic levels (0.5 mM) did not hinder BrO3- reduction but further increases in the levels to 1.0 mM decreased their reduction. Notably, S(IV)/Fe(III) process reduced 68% of 25.6 μg/L BrO3- in 3 min from tap water at pHini. 7.0, 0.02 mM Fe(III), and 1.0 mM S(IV), meeting drinking water standard (<10 μg/L). Also, ~99% of irons could be removed after the following activated carbon treatment. Moreover, sulfite radicals formed by S(IV) activation with Fe(III) were significant reactive species in the S(IV)/Fe(III) system. Reduction pathways were proposed accordingly. Collectively, S(IV)/Fe(III) process is a viable technology for reductively decontaminating realistic waters, especially when applied between the ozone-activated carbon process (i.e., the ozone-S(IV)/Fe(III)-activated carbon process).
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Affiliation(s)
- Qian Xiao
- State Key Laboratory of Pollution Control and Resource Reuse, College of Environmental Science and Engineering, Tongji University, Shanghai 200092, China; Shanghai Institute of Pollution Control and Ecological Security, Shanghai 200092, China
| | - Shuili Yu
- State Key Laboratory of Pollution Control and Resource Reuse, College of Environmental Science and Engineering, Tongji University, Shanghai 200092, China; Shanghai Institute of Pollution Control and Ecological Security, Shanghai 200092, China.
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Removal of Aniline and Benzothiazole Wastewaters Using an Efficient MnO 2/GAC Catalyst in a Photocatalytic Fluidised Bed Reactor. MATERIALS 2021; 14:ma14185207. [PMID: 34576439 PMCID: PMC8467099 DOI: 10.3390/ma14185207] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 08/18/2021] [Revised: 09/02/2021] [Accepted: 09/08/2021] [Indexed: 12/07/2022]
Abstract
This work presents an efficient method for treating industrial wastewater containing aniline and benzothiazole, which are refractory to conventional treatments. A combination of heterogeneous photocatalysis operating in a fluidised bed reactor is studied in order to increase mass transfer and reduce reaction times. This process uses a manganese dioxide catalyst supported on granular activated carbon with environmentally friendly characteristics. The manganese dioxide composite is prepared by hydrothermal synthesis on carbon Hydrodarco® 3000 with different active phase ratios. The support, the metal oxide, and the composite are characterised by performing Brunauer, Emmett, and Teller analysis, transmission electron microscopy, X-ray diffraction analysis, X-ray fluorescence analysis, UV-Vis spectroscopy by diffuse reflectance, and Fourier transform infrared spectroscopy in order to evaluate the influence of the metal oxide on the activated carbon. A composite of MnO2/GAC (3.78% in phase α-MnO2) is obtained, with a 9.4% increase in the specific surface of the initial GAC and a 12.79 nm crystal size. The effect of pH and catalyst load is studied. At a pH of 9.0 and a dose of 0.9 g L-1, a high degradation of aniline and benzothiazole is obtained, with an 81.63% TOC mineralisation in 64.8 min.
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25
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Markovskaya DV, Lyulyukin MN, Zhurenok AV, Kozlova EA. New Composite Photocatalysts Based on the Solid Solutions of Cadmium Sulfide, Zinc Sulfide, Titania, and Platinum for the Photocatalytic Reduction of Carbon Dioxide with Water Vapor under Visible Light. KINETICS AND CATALYSIS 2021. [DOI: 10.1134/s002315842104008x] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/23/2022]
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26
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Schneider G, Schweitzer B, Steinbach A, Pertics BZ, Cox A, Kőrösi L. Antimicrobial Efficacy and Spectrum of Phosphorous-Fluorine Co-Doped TiO 2 Nanoparticles on the Foodborne Pathogenic Bacteria Campylobacter jejuni, Salmonella Typhimurium, Enterohaemorrhagic E. coli, Yersinia enterocolitica, Shewanella putrefaciens, Listeria monocytogenes and Staphylococcus aureus. Foods 2021; 10:1786. [PMID: 34441563 PMCID: PMC8391345 DOI: 10.3390/foods10081786] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/15/2021] [Revised: 07/23/2021] [Accepted: 07/29/2021] [Indexed: 11/25/2022] Open
Abstract
Contamination of meats and meat products with foodborne pathogenic bacteria raises serious safety issues in the food industry. The antibacterial activities of phosphorous-fluorine co-doped TiO2 nanoparticles (PF-TiO2) were investigated against seven foodborne pathogenic bacteria: Campylobacter jejuni, Salmonella Typhimurium, Enterohaemorrhagic E. coli, Yersinia enterocolitica, Shewanella putrefaciens, Listeria monocytogenes and Staphylococcus aureus. PF-TiO2 NPs were synthesized hydrothermally at 250 °C for 1, 3, 6 or 12 h, and then tested at three different concentrations (500 μg/mL, 100 μg/mL, 20 μg/mL) for the inactivation of foodborne bacteria under UVA irradiation, daylight exposure or dark conditions. The antibacterial efficacies were compared after 30 min of exposure to light. Distinct differences in the antibacterial activities of the PF-TiO2 NPs, and the susceptibilities of tested foodborne pathogenic bacterium species were found. PF-TiO2/3 h and PF-TiO2/6 h showed the highest antibacterial activity by decreasing the living bacterial cell number from ~106 by ~5 log (L. monocytogenes), ~4 log (EHEC), ~3 log (Y. enterolcolitca, S. putrefaciens) and ~2.5 log (S. aureus), along with complete eradication of C. jejuni and S. Typhimurium. Efficacy of PF-TiO2/1 h and PF-TiO2/12 h NPs was lower, typically causing a ~2-4 log decrease in colony forming units depending on the tested bacterium while the effect of PF-TiO2/0 h was comparable to P25 TiO2, a commercial TiO2 with high photocatalytic activity. Our results show that PF-co-doping of TiO2 NPs enhanced the antibacterial action against foodborne pathogenic bacteria and are potential candidates for use in the food industry as active surface components, potentially contributing to the production of meats that are safe for consumption.
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Affiliation(s)
- György Schneider
- Department of Medical Microbiology and Immunology, Medical School, University of Pécs, Szigeti Street 12, H-7624 Pécs, Hungary; (B.S.); (A.S.); (B.Z.P.)
| | - Bettina Schweitzer
- Department of Medical Microbiology and Immunology, Medical School, University of Pécs, Szigeti Street 12, H-7624 Pécs, Hungary; (B.S.); (A.S.); (B.Z.P.)
| | - Anita Steinbach
- Department of Medical Microbiology and Immunology, Medical School, University of Pécs, Szigeti Street 12, H-7624 Pécs, Hungary; (B.S.); (A.S.); (B.Z.P.)
| | - Botond Zsombor Pertics
- Department of Medical Microbiology and Immunology, Medical School, University of Pécs, Szigeti Street 12, H-7624 Pécs, Hungary; (B.S.); (A.S.); (B.Z.P.)
| | - Alysia Cox
- Department of Biotechnology, Nanophagetherapy Center, Enviroinvest Corporation, Kertváros Street 2, H-7632 Pécs, Hungary;
| | - László Kőrösi
- Research Institute for Viticulture and Oenology, University of Pécs, Pázmány Péter Street 4, H-7634 Pécs, Hungary;
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You Y, Yuan H, Wu Y, Ma Y, Meng C, Zhao X. A novel red phosphorus/perylene diimide metal-free photocatalyst with p-n heterojunctions for efficient photoreduction of bromate under visible light. Sep Purif Technol 2021. [DOI: 10.1016/j.seppur.2021.118456] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/22/2022]
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28
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Recent advances in removal techniques of Cr(VI) toxic ion from aqueous solution: A comprehensive review. J Mol Liq 2021. [DOI: 10.1016/j.molliq.2020.115062] [Citation(s) in RCA: 175] [Impact Index Per Article: 58.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/14/2022]
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29
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Peiris S, Silva HB, Ranasinghe KN, Bandara SV, Perera IR. Recent development and future prospects of
TiO
2
photocatalysis. J CHIN CHEM SOC-TAIP 2021. [DOI: 10.1002/jccs.202000465] [Citation(s) in RCA: 26] [Impact Index Per Article: 8.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/16/2022]
Affiliation(s)
- Sasanka Peiris
- Australian Institute for Bioengineering and Nanotechnology University of Queensland St Lucia Queensland Australia
| | - Haritha B. Silva
- Department of Chemistry, Faculty of Science University of Peradeniya Peradeniya Sri Lanka
| | - Kumudu N. Ranasinghe
- Department of Chemistry, Faculty of Science University of Peradeniya Peradeniya Sri Lanka
| | - Sanjaya V. Bandara
- Department of Chemistry, Faculty of Science University of Peradeniya Peradeniya Sri Lanka
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Abstract
The presence of bromate in water sources generates environmental concern due to its toxicity for humans. Diverse technologies, like membranes, ion exchange, chemical reduction, etc., can be employed to treat bromate-polluted water but they produce waste that must be treated. An alternative to these technologies can be the catalytic reduction of bromate to bromide using hydrogen as a reducing agent. In this review, we analyze the research published about this catalytic technology. Specifically, we summarize and discuss about the state of knowledge related to (1) the different metals used as catalysts for the reaction; (2) the influence of the support on the catalytic activity; (3) the characterization of the catalysts; (4) the reaction mechanisms; and (5) the influence of the water composition in the catalytic activity and in the catalyst stability. Based on published papers, we analyze the strength and weaknesses of this technique and the possibilities of using this reaction for the treatment of bromate-polluted water as a sustainable process.
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Huang T, Tian F, Wen Z, Li G, Liang Y, Chen R. Synergistic mediation of metallic bismuth and oxygen vacancy in Bi/Bi 2WO 6-x to promote 1O 2 production for the photodegradation of bisphenol A and its analogues in water matrix. JOURNAL OF HAZARDOUS MATERIALS 2021; 403:123661. [PMID: 33264869 DOI: 10.1016/j.jhazmat.2020.123661] [Citation(s) in RCA: 28] [Impact Index Per Article: 9.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/06/2020] [Revised: 08/03/2020] [Accepted: 08/04/2020] [Indexed: 06/12/2023]
Abstract
Bi/Bi2WO6-x heterostructures has been successfully prepared by a facile one-step hydrothermal method. By maneuvering reaction time and Bi/W molar ratio of the precursors, we have been able to selectively introduce oxygen vacancy and metallic Bi into Bi2WO6 nanostructures. The obtained Bi/Bi2WO6-x heterostructures with more oxygen vacancy and moderate metallic Bi exhibit significantly improved photocatalytic activity for the photodegradation of bisphenol A (BPA) and its analogues due to its great ability for the generation of singlet oxygen (1O2), which has proven to work as the main reactive oxygen species during photocatalysis. It is also found the 1O2 concentration is highly depended on and modulated by the content of oxygen vacancy and metallic bismuth. Besides, we also demonstrate that the obtained Bi/Bi2WO6-x products display efficient photocatalytic performance toward BPA derivatives degradation and enhanced stability to resist the interferences in the water matrix.
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Affiliation(s)
- Teng Huang
- School of Chemistry and Environmental Engineering, Hubei Key Laboratory of Novel Reactor and Green Chemistry Technology, Wuhan Institute of Technology, Donghu New & High Technology Development Zone, Wuhan, 430205, PR China
| | - Fan Tian
- School of Chemistry and Environmental Engineering, Hubei Key Laboratory of Novel Reactor and Green Chemistry Technology, Wuhan Institute of Technology, Donghu New & High Technology Development Zone, Wuhan, 430205, PR China
| | - Zhipan Wen
- School of Chemistry and Environmental Engineering, Hubei Key Laboratory of Novel Reactor and Green Chemistry Technology, Wuhan Institute of Technology, Donghu New & High Technology Development Zone, Wuhan, 430205, PR China
| | - Guangfang Li
- Key Laboratory of Material Chemistry for Energy Conversion and Storage (Ministry of Education), Hubei Key Laboratory of Material Chemistry and Service Failure, School of Chemistry and Chemical Engineering, Huazhong University of Science and Technology (HUST), 1037 Luoyu Road, Wuhan, 430074, PR China.
| | - Ying Liang
- School of Chemical Engineering, Hubei University of Arts and Science, Xiangyang, 441053, PR China
| | - Rong Chen
- School of Chemistry and Environmental Engineering, Hubei Key Laboratory of Novel Reactor and Green Chemistry Technology, Wuhan Institute of Technology, Donghu New & High Technology Development Zone, Wuhan, 430205, PR China; Henan Institute of Advanced Technology, Zhengzhou University, Zhengzhou, 450002, PR China.
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Guo B, Tian Q, Oji T, Wang L, Sasaki K. Effects of Mg compounds in hydroxylated calcined dolomite as an effective and sustainable substitute of lime to precipitate as ettringite for treatment of selenite/selenate in aqueous solution. Colloids Surf A Physicochem Eng Asp 2021. [DOI: 10.1016/j.colsurfa.2020.125782] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
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Abstract
This article presents an overview of the reports on the doping of TiO2 with carbon, nitrogen, and sulfur, including single, co-, and tri-doping. A comparison of the properties of the photocatalysts synthesized from various precursors of TiO2 and C, N, or S dopants is summarized. Selected methods of synthesis of the non-metal doped TiO2 are also described. Furthermore, the influence of the preparation conditions on the doping mode (interstitial or substitutional) with reference to various types of the modified TiO2 is summarized. The mechanisms of photocatalysis for the different modes of the non-metal doping are also discussed. Moreover, selected applications of the non-metal doped TiO2 photocatalysts are shown, including the removal of organic compounds from water/wastewater, air purification, production of hydrogen, lithium storage, inactivation of bacteria, or carbon dioxide reduction.
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Talreja N, Ashfaq M, Chauhan D, Mera AC, Rodríguez CA. Strategic Doping Approach of the Fe-BiOI Microstructure: An Improved Photodegradation Efficiency of Tetracycline. ACS OMEGA 2021; 6:1575-1583. [PMID: 33490817 PMCID: PMC7818580 DOI: 10.1021/acsomega.0c05398] [Citation(s) in RCA: 7] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 11/05/2020] [Accepted: 12/23/2020] [Indexed: 06/12/2023]
Abstract
The present study describes the strategic doping of Fe metal ions into a BiOI microstructure using ex situ and in situ processes to synthesize a Fe-BiOI microstructure and their effect on photocatalytic degradation of tetracycline (TC). The data suggested that in situ Fe-BiOI (Fe-BiOI-In) has superior performance compared to ex situ Fe-BiOI (Fe-BiOI-Ex) due to the uniform dispersion of Fe within the Fe-BiOI material. Calculated bandgaps ∼1.8, ∼1.5, and 2.4 eV were observed for BiOI (without Fe), Fe-BiOI-In, and Fe-BiOI-Ex, respectively. Interestingly, Fe incorporation within BiOI might decrease the bandgap in Fe-BiOI-In due to the uniform distribution of metal ions, whereas increasing the bandgap in Fe-BiOI-Ex attributed to nonuniform distribution or agglomeration of metal ions. The uniform dispersion of Fe within Fe-BiOI modulates electronic properties as well as increases the exposure of Fe ions with TC, thereby higher degradation efficiency of TC. The in situ Fe-BiOI material shows 67 and 100% degradation of TC at 10 and 1 mg/L, respectively. The TC degradation was also found to be pH-dependent; when increasing the pH value up to 10, 94% degradation was achieved at 10 mg/L within 60 min of solar irradiation. The analysis was also performed over BiOI, which proves that Fe has a profound effect on TC degradation as Fe(II) tends to trigger oxidation-reduction by utilizing the chelate formation tendency of TC. Therefore, the prepared Fe-BiOI-In has the potential ability to degrade pharmaceutical compounds, especially, TC from wastewater.
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Affiliation(s)
- Neetu Talreja
- Multidisciplinary
Research Institute for Science and Technology, IIMCT, University of La Serena, La Serena 1700000, Chile
- Advanced
Ceramics and Nanotechnology Laboratory, Department of Materials Engineering,
Faculty of Engineering, University of Concepción, Concepción 4070409, Chile
| | - Mohammad Ashfaq
- Multidisciplinary
Research Institute for Science and Technology, IIMCT, University of La Serena, La Serena 1700000, Chile
- Advanced
Ceramics and Nanotechnology Laboratory, Department of Materials Engineering,
Faculty of Engineering, University of Concepción, Concepción 4070409, Chile
- School
of Life Science, BS AbdurRahaman Crescent
Institute of Science and Technology, Chennai 600048, India
| | - Divya Chauhan
- Department
of Chemical and Biomedical Engineering, University of South Florida, Tampa 33620, Florida, United States
| | - Adriana C. Mera
- Multidisciplinary
Research Institute for Science and Technology, IIMCT, University of La Serena, La Serena 1700000, Chile
| | - C. A. Rodríguez
- Multidisciplinary
Research Institute for Science and Technology, IIMCT, University of La Serena, La Serena 1700000, Chile
- Department
of Chemistry, Faculty of Sciences, University of La Serena, La Serena 1700000, Chile
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Lisco G, De Tullio A, Giagulli VA, De Pergola G, Triggiani V. Interference on Iodine Uptake and Human Thyroid Function by Perchlorate-Contaminated Water and Food. Nutrients 2020; 12:E1669. [PMID: 32512711 PMCID: PMC7352877 DOI: 10.3390/nu12061669] [Citation(s) in RCA: 17] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/14/2020] [Revised: 05/31/2020] [Accepted: 06/01/2020] [Indexed: 12/12/2022] Open
Abstract
BACKGROUND Perchlorate-induced natrium-iodide symporter (NIS) interference is a well-recognized thyroid disrupting mechanism. It is unclear, however, whether a chronic low-dose exposure to perchlorate delivered by food and drinks may cause thyroid dysfunction in the long term. Thus, the aim of this review was to overview and summarize literature results in order to clarify this issue. METHODS Authors searched PubMed/MEDLINE, Scopus, Web of Science, institutional websites and Google until April 2020 for relevant information about the fundamental mechanism of the thyroid NIS interference induced by orally consumed perchlorate compounds and its clinical consequences. RESULTS Food and drinking water should be considered relevant sources of perchlorate. Despite some controversies, cross-sectional studies demonstrated that perchlorate exposure affects thyroid hormone synthesis in infants, adolescents and adults, particularly in the case of underlying thyroid diseases and iodine insufficiency. An exaggerated exposure to perchlorate during pregnancy leads to a worse neurocognitive and behavioral development outcome in infants, regardless of maternal thyroid hormone levels. DISCUSSION AND CONCLUSION The effects of a chronic low-dose perchlorate exposure on thyroid homeostasis remain still unclear, leading to concerns especially for highly sensitive patients. Specific studies are needed to clarify this issue, aiming to better define strategies of detection and prevention.
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Affiliation(s)
- Giuseppe Lisco
- ASL Brindisi, Unit of Endocrinology, Metabolism & Clinical Nutrition, Hospital “A. Perrino”, Strada per Mesagne 7, 72100 Brindisi, Puglia, Italy;
| | - Anna De Tullio
- Interdisciplinary Department of Medicine—Section of Internal Medicine, Geriatrics, Endocrinology and Rare Diseases, University of Bari “Aldo Moro”, School of Medicine, Policlinico, Piazza Giulio Cesare 11, 70124 Bari, Puglia, Italy; (A.D.T.); (V.A.G.)
| | - Vito Angelo Giagulli
- Interdisciplinary Department of Medicine—Section of Internal Medicine, Geriatrics, Endocrinology and Rare Diseases, University of Bari “Aldo Moro”, School of Medicine, Policlinico, Piazza Giulio Cesare 11, 70124 Bari, Puglia, Italy; (A.D.T.); (V.A.G.)
- Clinic of Endocrinology and Metabolic Disease, Conversano Hospital, Via Edmondo de Amicis 36, 70014 Conversano, Bari, Puglia, Italy
| | - Giovanni De Pergola
- Department of Biomedical Sciences and Human Oncology, Section of Internal Medicine and Clinical Oncology, University of Bari Aldo Moro, Piazza Giulio Cesare 11, 70124 Bari, Puglia, Italy;
| | - Vincenzo Triggiani
- Interdisciplinary Department of Medicine—Section of Internal Medicine, Geriatrics, Endocrinology and Rare Diseases, University of Bari “Aldo Moro”, School of Medicine, Policlinico, Piazza Giulio Cesare 11, 70124 Bari, Puglia, Italy; (A.D.T.); (V.A.G.)
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Comparison of Ga2O3 and TiO2 Nanostructures for Photocatalytic Degradation of Volatile Organic Compounds. Catalysts 2020. [DOI: 10.3390/catal10050545] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/31/2022] Open
Abstract
The photocatalytic degradation of formaldehyde, acetaldehyde, toluene, and styrene are compared using monoclinic Ga2O3 and anatase TiO2 nanostructures under ultraviolet-C irradiation. These Ga2O3 and TiO2 photocatalysts are characterized using a field emission scanning electron microscope, a powder X-ray diffraction system, the Brunauer–Emmett–Teller method, and a Fourier transform infrared spectrometer. The Ga2O3 shows a higher reaction rate constant (k, min−1) than TiO2 by a factor of 7.1 for toluene, 8.1 for styrene, 3.1 for formaldehyde, and 2.0 for acetaldehyde. The results demonstrate that the photocatalytic activity ratio of the Ga2O3 over the TiO2 becomes more prominent toward the aromatic compounds compared with the nonaromatic compounds. Highly energetic photo-generated carriers on the conduction/valence band-edge of the Ga2O3, in comparison with that of the TiO2, result in superior photocatalytic activity, in particular on aromatic volatile organic compounds (VOCs) with a high bond dissociation energy.
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