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Zhong T, Huang W, Yao Z, Long X, Qu W, Zhao H, Tian S, Shu D, He C. Engineering of Graphitic Carbon Nitride (g-C 3N 4) Based Photocatalysts for Atmospheric Protection: Modification Strategies, Recent Progress, and Application Challenges. SMALL (WEINHEIM AN DER BERGSTRASSE, GERMANY) 2024:e2404696. [PMID: 39155427 DOI: 10.1002/smll.202404696] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/09/2024] [Revised: 07/13/2024] [Indexed: 08/20/2024]
Abstract
Graphitic carbon nitride (g-C3N4) is a prominent photocatalyst that has attracted substantial interest in the field of photocatalytic environmental remediation due to the low cost of fabrication, robust chemical structure, adaptable and tunable energy bandgaps, superior photoelectrochemical properties, cost-effective feedstocks, and distinctive framework. Nonetheless, the practical application of bulk g-C3N4 in the photocatalysis field is limited by the fast recombination of photogenerated e--h+ pairs, insufficient surface-active sites, and restricted redox capacity. Consequently, a great deal of research has been devoted to solving these scientific challenges for large-scale applications. This review concisely presents the latest advancements in g-C3N4-based photocatalyst modification strategies, and offers a comprehensive analysis of the benefits and preparation techniques for each strategy. It aims to articulate the complex relationship between theory, microstructure, and activities of g-C3N4-based photocatalysts for atmospheric protection. Finally, both the challenges and opportunities for the development of g-C3N4-based photocatalysts are highlighted. It is highly believed that this special review will provide new insight into the synthesis, modification, and broadening of g-C3N4-based photocatalysts for atmospheric protection.
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Affiliation(s)
- Tao Zhong
- Guangdong Provincial Key Laboratory of Environmental Pollution Control and Remediation Technology, School of Environmental Science and Engineering, Sun Yat-Sen University, Guangzhou, 510275, China
| | - Wenbin Huang
- Guangdong Provincial Key Laboratory of Environmental Pollution Control and Remediation Technology, School of Environmental Science and Engineering, Sun Yat-Sen University, Guangzhou, 510275, China
| | - Zhangnan Yao
- Guangdong Provincial Key Laboratory of Environmental Pollution Control and Remediation Technology, School of Environmental Science and Engineering, Sun Yat-Sen University, Guangzhou, 510275, China
| | - Xianhu Long
- Guangdong Provincial Key Laboratory of Environmental Pollution Control and Remediation Technology, School of Environmental Science and Engineering, Sun Yat-Sen University, Guangzhou, 510275, China
| | - Wei Qu
- Guangdong Provincial Key Laboratory of Environmental Pollution Control and Remediation Technology, School of Environmental Science and Engineering, Sun Yat-Sen University, Guangzhou, 510275, China
| | - Huinan Zhao
- Guangdong Provincial Key Laboratory of Environmental Pollution Control and Remediation Technology, School of Environmental Science and Engineering, Sun Yat-Sen University, Guangzhou, 510275, China
| | - Shuanghong Tian
- Guangdong Provincial Key Laboratory of Environmental Pollution Control and Remediation Technology, School of Environmental Science and Engineering, Sun Yat-Sen University, Guangzhou, 510275, China
| | - Dong Shu
- Key Lab of Technology on Electrochemical Energy Storage and Power Generation in Guangdong Universities, School of Chemistry, South China Normal University, Guangzhou, 510006, China
| | - Chun He
- Guangdong Provincial Key Laboratory of Environmental Pollution Control and Remediation Technology, School of Environmental Science and Engineering, Sun Yat-Sen University, Guangzhou, 510275, China
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Kalidasan K, Mallapur S, Munirathnam K, Nagarajaiah H, Reddy MBM, Kakarla RR, Raghu AV. Transition metals-doped g-C 3N 4 nanostructures as advanced photocatalysts for energy and environmental applications. CHEMOSPHERE 2024; 352:141354. [PMID: 38311034 DOI: 10.1016/j.chemosphere.2024.141354] [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: 08/31/2023] [Revised: 01/07/2024] [Accepted: 01/31/2024] [Indexed: 02/06/2024]
Abstract
Graphitic carbon nitride (g-C3N4)-based heterostructured photocatalysts have received significant attention for its potential applications in the treatment of wastewater and hydrogen evolution. The utilization of semiconductor materials in heterogeneous photocatalysis has recently received great attention due to their potential and eco-friendly properties. Doping with metal ions plays a crucial role in altering the photochemical characteristics of g-C3N4, effectively enhancing photoabsorption into the visible range and thus improving the photocatalytic performance of doped photocatalysts. As an emerging nanomaterial, nanostructured g-C3N4 represents a visible light-active semiconducting photocatalyst that has attracted significant interest in the photocatalysis field, particularly for its practical water treatment applications. To the best of our knowledge, investigations of functionalized photocatalytic (PC) materials on 3d transition metal-doped g-C3N4 remain unexplored in the existing literature. g-C3N4 based heterohybrid photocatalysts have demonstrated excellent reusability, making them highly promising for wastewater treatment applications. This paper describes the overview of numerous studies conducted on the heterostructured g-C3N4 photocatalysts with various 3d metals. Research studies have revealed that the introduction of element doping with various 3d transition metals (e.g., Ti, Mn, Fe, Co, Ni, Cu, Zn, etc.) into g-C3N4 is an efficient approach to enhance degradation efficacy and boost photocatalytic activity (PCA) of doped g-C3N4 catalysts. Moreover, the significance of g-C3N4 heterostructured nanohybrids is highlighted, particularly in the context of wastewater treatment applications. The study concludes by providing insights into future perspectives in this developing area of research, with a specific focus on the degradation of various organic contaminants.
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Affiliation(s)
- Kavya Kalidasan
- Department of Chemistry, School of Applied Sciences, REVA University, Kattigenahalli, Yelahanka, Bangalore, 560064, India
| | - Srinivas Mallapur
- Department of Chemistry, School of Applied Sciences, REVA University, Kattigenahalli, Yelahanka, Bangalore, 560064, India.
| | - K Munirathnam
- Department of Physics, School of Applied Sciences, REVA University, Kattigenahalli, Yelahanka, Bangalore, 560064, India
| | - H Nagarajaiah
- Department of Chemistry, School of Applied Sciences, REVA University, Kattigenahalli, Yelahanka, Bangalore, 560064, India
| | - M B Madhusudana Reddy
- Department of Chemistry, School of Applied Sciences, REVA University, Kattigenahalli, Yelahanka, Bangalore, 560064, India
| | - Raghava Reddy Kakarla
- School of Chemical and Biomolecular Engineering, The University of Sydney, Sydney, NSW 2006, Australia.
| | - Anjanapura V Raghu
- Faculty of Allied Health Sciences, BLDE (Deemed-to-be University), Vijayapura, 586103, Karnataka, India.
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Feng G, Huang H, Zhang M, Wu Z, Sun D, Chen Q, Yang D, Zheng Y, Chen Y, Jing X. Single Atom Iron-Doped Graphic-Phase C 3 N 4 Semiconductor Nanosheets for Augmented Sonodynamic Melanoma Therapy Synergy with Endowed Chemodynamic Effect. ADVANCED SCIENCE (WEINHEIM, BADEN-WURTTEMBERG, GERMANY) 2023; 10:e2302579. [PMID: 37282773 PMCID: PMC10427360 DOI: 10.1002/advs.202302579] [Citation(s) in RCA: 16] [Impact Index Per Article: 16.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/22/2023] [Indexed: 06/08/2023]
Abstract
Sonodynamic therapy (SDT) is a non-invasive therapeutic modality with high tissue-penetration depth to induce reactive oxygen species (ROS) generation for tumor treatment. However, the clinical translation of SDT is restricted seriously by the lack of high-performance sonosensitizers. Herein, the distinct single atom iron (Fe)-doped graphitic-phase carbon nitride (C3 N4 ) semiconductor nanosheets (Fe-C3 N4 NSs) are designed and engineered as chemoreactive sonosensitizers to effectively separate the electrons (e- ) and holes (h+ ) pairs, achieving high yields of ROS generation against melanoma upon ultrasound (US) activation. Especially, the single atom Fe doping not only substantially elevates the separation efficiency of the e- -h+ pairs involved in SDT, but also can serve as high-performance peroxidase mimetic enzyme to catalyze the Fenton reaction for generating abundant hydroxyl radicals, therefore synergistically augmenting the curative effect mediated by SDT. As verified by density functional theory simulation, the doping of Fe atom significantly promotes the charge redistribution in the C3 N4 -based NSs, which improves their synergistic SDT/chemodynamic activities. Both the in vitro and in vivo assays demonstrate that Fe-C3 N4 NSs feature an outstanding antitumor effect by aggrandizing the sono-chemodynamic effect. This work illustrates a unique single-atom doping strategy for ameliorating the sonosensitizers, and also effectively expands the innovative anticancer-therapeutic applications of semiconductor-based inorganic sonosensitizers.
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Affiliation(s)
- Guiying Feng
- Department of UltrasonographyHainan General Hospital/Hainan Affiliated Hospital of Hainan Medical University570311HaikouP. R. China
| | - Hui Huang
- Materdicine Lab, School of Life SciencesShanghai UniversityShanghai200444P. R. China
| | - Min Zhang
- Department of UltrasonographyHainan General Hospital/Hainan Affiliated Hospital of Hainan Medical University570311HaikouP. R. China
| | - Zhuole Wu
- Department of UltrasonographyHainan General Hospital/Hainan Affiliated Hospital of Hainan Medical University570311HaikouP. R. China
| | - Dandan Sun
- Department of UltrasonographyHainan General Hospital/Hainan Affiliated Hospital of Hainan Medical University570311HaikouP. R. China
| | - Qiqing Chen
- Department of UltrasonographyHainan General Hospital/Hainan Affiliated Hospital of Hainan Medical University570311HaikouP. R. China
| | - Dayan Yang
- Department of UltrasonographyHainan General Hospital/Hainan Affiliated Hospital of Hainan Medical University570311HaikouP. R. China
| | - Yuanyi Zheng
- Department of Ultrasound in MedicineShanghai Jiao Tong University Affiliated Sixth People’s Hospital, Shanghai Institute of Ultrasound in Medicine200032ShanghaiP. R. China
| | - Yu Chen
- Materdicine Lab, School of Life SciencesShanghai UniversityShanghai200444P. R. China
| | - Xiangxiang Jing
- Department of UltrasonographyHainan General Hospital/Hainan Affiliated Hospital of Hainan Medical University570311HaikouP. R. China
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Shen J, Shi A, Lu J, Lu X, Zhang H, Jiang Z. Optimized fabrication of Cu-doped ZnO/calcined CoFe‒LDH composite for efficient degradation of bisphenol a through synergistic visible-light photocatalysis and persulfate activation: Performance and mechanisms. ENVIRONMENTAL POLLUTION (BARKING, ESSEX : 1987) 2023; 323:121186. [PMID: 36773684 DOI: 10.1016/j.envpol.2023.121186] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/14/2022] [Revised: 01/16/2023] [Accepted: 01/30/2023] [Indexed: 06/18/2023]
Abstract
A novel magnetically separable Cu/ZnO/CoFe‒CLDH composite, whose synthesis was optimized using the Taguchi approach, was optimally synthesized by hydrothermally coupling Cu-doped ZnO and calcined CoFe-LDH. The synthesized Cu/ZnO/CoFe‒CLDH was applied to construct a synergistic process of integrating visible-light photocatalysis (VPC) with persulfate activation (PSA) and to degrade bisphenol A (BPA). Various characterizations proved that Cu/ZnO/CoFe‒CLDH possessed excellent physicochemical, optoelectronic and magnetic properties, thereby enhancing the catalytic performance. The Cu/ZnO/CoFe‒CLDH composite achieved highly efficient BPA degradation during the synergistic VPC‒PSA process, and its reaction rate constant (0.74 h-1) was 6.17-, 4.11-, and 2.85-fold higher than that of Cu/ZnO, CoFe‒CLDH, and Cu/ZnO/CoFe‒CLDH (VPC only), respectively. Moreover, the effects of the catalyst dosage, initial pollutant concentration, solution pH, persulfate dosage and coexisting ions on BPA degradation were comprehensively investigated. Radical-trapping experiments revealed that the contributions of ·OH, SO4·‒, ·O2-, and 1O2 involved in BPA degradation. Based on the intermediates identified by LC/MS, the main BPA degradation pathways were determined, the overall trend of which reflects a decreasing ecotoxicity. This study verified the effectiveness of the synergistic VPC‒PSA process with Cu/ZnO/CoFe‒CLDH, which could be used as a new reference for removing organic micropollutants from water.
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Affiliation(s)
- Jyunhong Shen
- College of Ecological Environment and Urban Construction, Fujian University of Technology, Fuzhou, Fujian, 350118, China
| | - Antong Shi
- College of Ecological Environment and Urban Construction, Fujian University of Technology, Fuzhou, Fujian, 350118, China
| | - Jiahui Lu
- College of Ecological Environment and Urban Construction, Fujian University of Technology, Fuzhou, Fujian, 350118, China
| | - Xiangtao Lu
- College of Ecological Environment and Urban Construction, Fujian University of Technology, Fuzhou, Fujian, 350118, China
| | - Hongyu Zhang
- College of Ecological Environment and Urban Construction, Fujian University of Technology, Fuzhou, Fujian, 350118, China
| | - Zhuwu Jiang
- College of Ecological Environment and Urban Construction, Fujian University of Technology, Fuzhou, Fujian, 350118, China.
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Sun X, Li C, Yu B, Wang J, Wang W. Removal of gaseous volatile organic compounds via vacuum ultraviolet photodegradation: Review and prospect. J Environ Sci (China) 2023; 125:427-442. [PMID: 36375926 DOI: 10.1016/j.jes.2022.01.020] [Citation(s) in RCA: 6] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/20/2021] [Revised: 01/10/2022] [Accepted: 01/17/2022] [Indexed: 06/16/2023]
Abstract
Volatile organic compounds (VOCs) have attracted much attention for decades as they are the precursors of photochemical smog and are harmful to the environment and human health. Vacuum ultraviolet (VUV) photodegradation is a simple and effective method to decompose VOCs (ranging from tens to hundreds of ppmV) without additional oxidants or catalysts in the air at atmospheric pressure. In this paper, we review the research progress of VOCs removal via VUV photodegradation. The fundamentals are outlined and the key operation factors for VOCs degradation, such as humidity, oxygen content, VOCs initial concentration, light intensity, and flow rate, are discussed. VUV photodegradation of VOCs mixture is elucidated. The application of VUV photodegradation in combination with ozone-assisted catalytic oxidation (OZCO) and photocatalytic oxidation (PCO) systems, and as the pre-treatment technique for biological purification are illustrated. Based on the summary, we propose the challenges of VUV photodegradation and perspectives for its future development.
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Affiliation(s)
- Xue Sun
- School of Civil and Environmental Engineering, Harbin Institute of Technology, Shenzhen 518055, China
| | - Chaolin Li
- School of Civil and Environmental Engineering, Harbin Institute of Technology, Shenzhen 518055, China.
| | - Boping Yu
- Shenzhen Academy of Environmental Sciences, Shenzhen 518001, China
| | - Jingwen Wang
- School of Civil and Environmental Engineering, Harbin Institute of Technology, Shenzhen 518055, China
| | - Wenhui Wang
- School of Civil and Environmental Engineering, Harbin Institute of Technology, Shenzhen 518055, China.
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Zhang Q, Guo F, Yu L, Wang B, Ding J, Fan L, Wu Y, Yang B, Xu Q. Efficient Degradation of Toluene over MnO 2/TiO 2 Nanobelts under Vacuum Ultraviolet Irradiation. Ind Eng Chem Res 2023. [DOI: 10.1021/acs.iecr.2c03256] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/11/2023]
Affiliation(s)
- Qi Zhang
- School of Environmental Science and Engineering, Yancheng Institute of Technology, Yancheng224051, P. R. China
| | - Fang Guo
- School of Chemistry and Chemical Engineering, Yancheng Institute of Technology, Yancheng224051, P. R. China
| | - Liangyun Yu
- School of Light Industry, Beijing Technology and Business University, No. 11 Fucheng Road, Beijing100048, P. R. China
| | - Bailin Wang
- School of Chemistry and Chemical Engineering, Yancheng Institute of Technology, Yancheng224051, P. R. China
| | - Jingya Ding
- School of Chemistry and Chemical Engineering, Yancheng Institute of Technology, Yancheng224051, P. R. China
| | - Lan Fan
- Yancheng Lanfeng Environmental Engineering Technology Co, Ltd, Yancheng224051, P. R. China
| | - Yifan Wu
- School of Environmental Science and Engineering, Yancheng Institute of Technology, Yancheng224051, P. R. China
| | - Bairen Yang
- School of Environmental Science and Engineering, Yancheng Institute of Technology, Yancheng224051, P. R. China
| | - Qi Xu
- School of Chemistry and Chemical Engineering, Yancheng Institute of Technology, Yancheng224051, P. R. China
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Mehralipour J, Jonidi Jafari A, Gholami M, Esrafili A, Kermani M. Photocatalytic-Proxone Process Application in the Degradation of Toluene-Diisocyante, and Methylene Diphenyl Diisocyanate from polluted air. J Photochem Photobiol A Chem 2023. [DOI: 10.1016/j.jphotochem.2023.114549] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/15/2023]
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Ajmal Z, Haq MU, Naciri Y, Djellabi R, Hassan N, Zaman S, Murtaza A, Kumar A, Al-Sehemi AG, Algarni H, Al-Hartomy OA, Dong R, Hayat A, Qadeer A. Recent advancement in conjugated polymers based photocatalytic technology for air pollutants abatement: Cases of CO 2, NO x, and VOCs. CHEMOSPHERE 2022; 308:136358. [PMID: 36087730 DOI: 10.1016/j.chemosphere.2022.136358] [Citation(s) in RCA: 12] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/22/2022] [Revised: 09/01/2022] [Accepted: 09/02/2022] [Indexed: 06/15/2023]
Abstract
According to World Health Organization (WHO) survey, air pollution has become the major reason of several fatal diseases, which had led to the death of 7 million peoples around the globe. The 9 people out of 10 breathe air, which exceeds WHO recommendations. Several strategies are in practice to reduce the emission of pollutants into the air, and also strict industrial, scientific, and health recommendations to use sustainable green technologies to reduce the emission of contaminants into the air. Photocatalysis technology recently has been raised as a green technology to be in practice towards the removal of air pollutants. The scientific community has passed a long pathway to develop such technology from the material, and reactor points of view. Many classes of photoactive materials have been suggested to achieve such a target. In this context, the contribution of conjugated polymers (CPs), and their modification with some common inorganic semiconductors as novel photocatalysts, has never been addressed in literature till now for said application, and is critically evaluated in this review. As we know that CPs have unique characteristics compared to inorganic semiconductors, because of their conductivity, excellent light response, good sorption ability, better redox charge generation, and separation along with a delocalized π-electrons system. The advances in photocatalytic removal/reduction of three primary air-polluting compounds such as CO2, NOX, and VOCs using CPs based photocatalysts are discussed in detail. Furthermore, the synergetic effects, obtained in CPs after combining with inorganic semiconductors are also comprehensively summarized in this review. However, such a combined system, on to better charges generation and separation, may make the Adsorb & Shuttle process into action, wherein, CPs may play the sorbing area. And, we hope that, the critical discussion on the further enhancement of photoactivity and future recommendations will open the doors for up-to-date technology transfer in modern research.
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Affiliation(s)
- Zeeshan Ajmal
- School of Chemistry and Chemical Engineering, Northwestern Polytechnical University, Xian, 710072, China; MoA Key Laboratory for Clean Production and Utilization of Renewable Energy, MoST National Center for International Research of BioEnergy Science and Technology, College of Engineering, China Agricultural University, Beijing, 100083, China
| | - Mahmood Ul Haq
- Key Laboratory of the Ministry of Education for Advanced Catalysis Materials, College of Chemistry and Life Sciences, Zhejiang Normal University, Jinhua, 321004, China
| | - Yassine Naciri
- Laboratoire Matériaux et Environnement LME, Faculté des Sciences, Université Ibn Zohr, BP, Cité Dakhla, Agadir, 8106, Morocco
| | - Ridha Djellabi
- Department of Chemical Engineering, Universitat Rovira I Virgili, Tarragona, 43007, Spain.
| | - Noor Hassan
- School of Chemistry and Chemical Engineering, Beijing Institute of Technology, Beijing, PR, 100081, China
| | - Shahid Zaman
- Key Laboratory of Energy Conversion and Storage Technologies, Department of Mechanical and Energy Engineering, Southern University of Science and Technology, Shenzhen, 518055, PR China
| | - Adil Murtaza
- MOE Key Laboratory for Non-equilibrium Synthesis and Modulation of Condensed Matter, State Key Laboratory for Mechanical Behaviour of Materials, Key Laboratory of Advanced Functional Materials and Mesoscopic Physics of Shaanxi Province, School of Physics, Xian Jiaotong University, Xian, Shaanxi, 710049, PR China
| | - Anuj Kumar
- Nanotechnology Laboratory, Department of Chemistry, GLA, University, Mathura, Uttar Pradesh, 281406, India
| | - Abdullah G Al-Sehemi
- Research Center for Advanced Materials Science (RCAMS), King Khalid University, P.O. Box 9004, Abha, 61413, Saudi Arabia; Department of Chemistry, College of Science, King Khalid University, P.O. Box 9004, Abha, 61413, Saudi Arabia
| | - Hamed Algarni
- Research Center for Advanced Materials Science (RCAMS), King Khalid University, P.O. Box 9004, Abha, 61413, Saudi Arabia; Department of Physics, Faculty of Science, King Khalid University, P.O. Box 9004, Abha, 61413, Saudi Arabia
| | - Omar A Al-Hartomy
- Department of Physics, Faculty of Science, King Abdulaziz University, Jeddah, 21589, Saudi Arabia
| | - R Dong
- MoA Key Laboratory for Clean Production and Utilization of Renewable Energy, MoST National Center for International Research of BioEnergy Science and Technology, College of Engineering, China Agricultural University, Beijing, 100083, China
| | - Asif Hayat
- College of Chemistry and Life Sciences, Zhejiang Normal University, Jinhua, Zhejiang, 321004, China; College of Geography and Environmental Sciences, Zhejiang Normal University, Jinhua, 321004, China.
| | - Abdul Qadeer
- State Key Laboratory of Environmental Criteria and Risk Assessment, National Engineering Laboratory for Lake Pollution Control and Ecological Restoration, Chinese Research Academy of Environmental Sciences, Beijing, 100012, China.
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Removal and mineralization of toluene under VUV/UV lamp irradiation in humid air: Effect of light wavelength, O2 and H2O. ARAB J CHEM 2022. [DOI: 10.1016/j.arabjc.2022.104108] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/24/2022] Open
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Liu B, Ji J, Zhang B, Huang W, Gan Y, Leung DYC, Huang H. Catalytic ozonation of VOCs at low temperature: A comprehensive review. JOURNAL OF HAZARDOUS MATERIALS 2022; 422:126847. [PMID: 34416698 DOI: 10.1016/j.jhazmat.2021.126847] [Citation(s) in RCA: 71] [Impact Index Per Article: 35.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/23/2021] [Revised: 07/31/2021] [Accepted: 08/04/2021] [Indexed: 06/13/2023]
Abstract
VOCs abatement has attracted increasing interest because of the detrimental effects on both atmospheric environment and human beings of VOCs. The assistance of ozone has enabled efficient VOCs removal at low temperature. Thereby, catalytic ozonation is considered as one of the most feasible and effective methods for VOCs elimination. This work systematically reviews the emerging advances of catalytic ozonation of different VOCs (i.e., aromatic hydrocarbons, oxygenated VOCs, chlorinated VOCs, sulfur-containing VOCs, and saturated alkanes) over various functional catalysts. General reaction mechanism of catalytic ozonation including both Langmuir-Hinshelwood and Mars-van-Krevelen mechanisms was proposed depending on the reactive oxygen species involving the reactions. The influence of reaction conditions (water vapor and temperature) is fully discussed. This review also introduces the enhanced VOCs oxidation via catalytic ozonation in the ozone-generating systems including plasma and vacuum ultraviolet. Lastly, the existing challenges of VOCs catalytic ozonation are presented, and the perspective of this technology is envisioned.
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Affiliation(s)
- Biyuan Liu
- School of Environmental Science and Engineering, Sun Yat-sen University, Guangzhou 510006, China
| | - Jian Ji
- School of Environmental Science and Engineering, Sun Yat-sen University, Guangzhou 510006, China
| | - Boge Zhang
- School of Environmental Science and Engineering, Sun Yat-sen University, Guangzhou 510006, China
| | - Wenjun Huang
- School of Environmental Science and Engineering, Sun Yat-sen University, Guangzhou 510006, China
| | - Yanling Gan
- School of Environmental Science and Engineering, Sun Yat-sen University, Guangzhou 510006, China
| | - Dennis Y C Leung
- Department of Mechanical Engineering, The University of Hong Kong, Hong Kong, China
| | - Haibao Huang
- School of Environmental Science and Engineering, Sun Yat-sen University, Guangzhou 510006, China; Guangdong Indoor Air Pollution Control Engineering Research Center, Guangzhou 510006, China.
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Zhou M, Ou H, Li S, Qin X, Fang Y, Lee S, Wang X, Ho W. Photocatalytic Air Purification Using Functional Polymeric Carbon Nitrides. ADVANCED SCIENCE (WEINHEIM, BADEN-WURTTEMBERG, GERMANY) 2021; 8:e2102376. [PMID: 34693667 PMCID: PMC8693081 DOI: 10.1002/advs.202102376] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/07/2021] [Revised: 08/20/2021] [Indexed: 05/19/2023]
Abstract
The techniques for the production of the environment have received attention because of the increasing air pollution, which results in a negative impact on the living environment of mankind. Over the decades, burgeoning interest in polymeric carbon nitride (PCN) based photocatalysts for heterogeneous catalysis of air pollutants has been witnessed, which is improved by harvesting visible light, layered/defective structures, functional groups, suitable/adjustable band positions, and existing Lewis basic sites. PCN-based photocatalytic air purification can reduce the negative impacts of the emission of air pollutants and convert the undesirable and harmful materials into value-added or nontoxic, or low-toxic chemicals. However, based on previous reports, the systematic summary and analysis of PCN-based photocatalysts in the catalytic elimination of air pollutants have not been reported. The research progress of functional PCN-based composite materials as photocatalysts for the removal of air pollutants is reviewed here. The working mechanisms of each enhancement modification are elucidated and discussed on structures (nanostructure, molecular structue, and composite) regarding their effects on light-absorption/utilization, reactant adsorption, intermediate/product desorption, charge kinetics, and reactive oxygen species production. Perspectives related to further challenges and directions as well as design strategies of PCN-based photocatalysts in the heterogeneous catalysis of air pollutants are also provided.
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Affiliation(s)
- Min Zhou
- Department of Science and Environmental StudiesThe Education University of Hong KongTai Po, New TerritoriesHong KongP. R. China
| | - Honghui Ou
- Department of ChemistryTsinghua UniversityBeijing100084P. R. China
| | - Shanrong Li
- State Key Laboratory of Photocatalysis on Energy and EnvironmentCollege of ChemistryFuzhou UniversityFuzhou350116P. R. China
| | - Xing Qin
- Department of Science and Environmental StudiesThe Education University of Hong KongTai Po, New TerritoriesHong KongP. R. China
| | - Yuanxing Fang
- State Key Laboratory of Photocatalysis on Energy and EnvironmentCollege of ChemistryFuzhou UniversityFuzhou350116P. R. China
| | - Shun‐cheng Lee
- Department of Civil and Environmental EngineeringThe Hong Kong Polytechnic UniversityHong KongP. R. China
| | - Xinchen Wang
- State Key Laboratory of Photocatalysis on Energy and EnvironmentCollege of ChemistryFuzhou UniversityFuzhou350116P. R. China
| | - Wingkei Ho
- Department of Science and Environmental StudiesThe Education University of Hong KongTai Po, New TerritoriesHong KongP. R. China
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12
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Kuchmiy SY. Photocatalytic Air Decontamination from Volatile Organic Pollutants Using Graphite-Like Carbon Nitride: a Review. THEOR EXP CHEM+ 2021. [DOI: 10.1007/s11237-021-09693-3] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/19/2022]
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13
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14
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Yang L, Guo J, Yang T, Guo C, Zhang S, Luo S, Dai W, Li B, Luo X, Li Y. Self-assembly Cu 2O nanowire arrays on Cu mesh: A solid-state, highly-efficient, and stable photocatalyst for toluene degradation under sunlight. JOURNAL OF HAZARDOUS MATERIALS 2021; 402:123741. [PMID: 33254768 DOI: 10.1016/j.jhazmat.2020.123741] [Citation(s) in RCA: 9] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/03/2020] [Revised: 08/04/2020] [Accepted: 08/15/2020] [Indexed: 06/12/2023]
Abstract
Sunlight driven photocatalysis offers an effective and eco-friendly technology for volatile organic compounds (VOCs) removal. Three dimensional (3D) and oriented structure can facilitate efficient photon absorption and rapid diffusion of VOCs, which prevails over the powder-formed catalysts. Herein, free-standing and uniform p-type Cu2O nanowire (NW) arrays were obtained through heat treatment of Cu(OH)2 NWs, which were spontaneously grown from Cu mesh in air under room temperature for the first time. The as-prepared Cu2O NWs show excellent degradation performance in decomposing 30 ppm toluene (99.9 % within 120 min) and high stability (no decline after ten recycles). The toluene degradation was also conducted under the natural sunlight, demonstrating complete removal from 12:00 am to 15:00 pm. During photocatalysis, toluene is attacked by the photogenerated holes (h+) and hydroxyl radicals (·OH), and finally oxidized to nontoxic small molecules. The photocatalytic removing toluene with Cu2O NWs/Cu mesh has a promising application prospect owing to its low cost, high efficiency, stability, and convenient operation.
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Affiliation(s)
- Lixia Yang
- Key Laboratory of Jiangxi Province for Persistent Pollutants Control and Resources Recycle, Nanchang Hangkong University, Nanchang 330063, PR China
| | - Jiawei Guo
- Key Laboratory of Jiangxi Province for Persistent Pollutants Control and Resources Recycle, Nanchang Hangkong University, Nanchang 330063, PR China
| | - Tianqiao Yang
- Key Laboratory of Jiangxi Province for Persistent Pollutants Control and Resources Recycle, Nanchang Hangkong University, Nanchang 330063, PR China
| | - Chao Guo
- Key Laboratory of Jiangxi Province for Persistent Pollutants Control and Resources Recycle, Nanchang Hangkong University, Nanchang 330063, PR China
| | - Shuqu Zhang
- Key Laboratory of Jiangxi Province for Persistent Pollutants Control and Resources Recycle, Nanchang Hangkong University, Nanchang 330063, PR China.
| | - Shenglian Luo
- Key Laboratory of Jiangxi Province for Persistent Pollutants Control and Resources Recycle, Nanchang Hangkong University, Nanchang 330063, PR China.
| | - Weili Dai
- Key Laboratory of Jiangxi Province for Persistent Pollutants Control and Resources Recycle, Nanchang Hangkong University, Nanchang 330063, PR China
| | - Bing Li
- Key Laboratory of Jiangxi Province for Persistent Pollutants Control and Resources Recycle, Nanchang Hangkong University, Nanchang 330063, PR China
| | - Xubiao Luo
- Key Laboratory of Jiangxi Province for Persistent Pollutants Control and Resources Recycle, Nanchang Hangkong University, Nanchang 330063, PR China
| | - Yue Li
- School of Materials and Chemical Engineering, Henan University of Engineering, Zhengzhou, Henan 451191, PR China
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15
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Ma Q, Ning P, Wang X, Wang L, Xu L, Ma Y, Zhang Y, Tao L, Liu W, Hao J. Efficient removal of thallium from flow gas using manganite‐based catalysts by gas–solid‐phase catalytic oxidation at low temperature. Appl Organomet Chem 2021. [DOI: 10.1002/aoc.6034] [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]
Affiliation(s)
- Qiang Ma
- Faculty of Environmental Science and Engineering Kunming University of Science and Technology Kunming China
- Sichuan Academy of Environmental Science Chengdu China
| | - Ping Ning
- Faculty of Environmental Science and Engineering Kunming University of Science and Technology Kunming China
| | - Xueqian Wang
- Faculty of Environmental Science and Engineering Kunming University of Science and Technology Kunming China
| | - Langlang Wang
- Faculty of Environmental Science and Engineering Kunming University of Science and Technology Kunming China
| | - Lixia Xu
- Yunnan Ecological and Environmental Monitoring Center Kunming China
| | - Yixing Ma
- Faculty of Environmental Science and Engineering Kunming University of Science and Technology Kunming China
| | - Yingjie Zhang
- Faculty of Environmental Science and Engineering Kunming University of Science and Technology Kunming China
| | - Lei Tao
- Faculty of Environmental Science and Engineering Kunming University of Science and Technology Kunming China
| | - Wei Liu
- Faculty of Environmental Science and Engineering Kunming University of Science and Technology Kunming China
| | - Jiming Hao
- State Key Joint Laboratory of Environment Simulation and Pollution Control, School of Environment Tsinghua University Beijing China
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16
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Porous graphitic carbon nitride nanosheets for photocatalytic degradation of formaldehyde gas. Chem Phys Lett 2021. [DOI: 10.1016/j.cplett.2020.138132] [Citation(s) in RCA: 7] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/06/2023]
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17
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Li Q, Li FT. Recent advances in surface and interface design of photocatalysts for the degradation of volatile organic compounds. Adv Colloid Interface Sci 2020; 284:102275. [PMID: 32987294 DOI: 10.1016/j.cis.2020.102275] [Citation(s) in RCA: 19] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/18/2020] [Revised: 09/18/2020] [Accepted: 09/19/2020] [Indexed: 02/03/2023]
Abstract
Photocatalysis has attracted wide attention in eliminating volatile organic compounds (VOCs). This paper pays attention to the relationship between structure and performance of photocatalysts based on the fact that catalytic reactions arise on the surface of catalysts and the interface structure of photocatalysts plays key role in transfer efficiency of charges carriers. This review summarizes various surface/interface designs including unsaturated coordination such as oxygen vacancies, surface halogenations, and heterojunctions, homojunctions, facets, etc., as well as the application in photocatalytic degradation of VOCs. This paper reviews the influence of surface and interface properties of materials on VOCs molecules, effective strategies to promote the decomposition of VOCs from the perspectives of VOCs activation, reaction barrier etc., and presents various methods of photocatalyst design appropriately. The degradation path of highly toxic benzene VOCs are also summarized. In addition, the possible problems and suggestions for photocatalytic degradation of VOCs are proposed.
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Affiliation(s)
- Qi Li
- College of Science, Hebei University of Science and Technology, Shijiazhuang 050018, China
| | - Fa-Tang Li
- College of Science, Hebei University of Science and Technology, Shijiazhuang 050018, China; School of Environmental and Chemical Engineering, Yanshan University, Qinhuangdao 066004, China.
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18
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Zeng Y, Zhan Y, Xie R, Hu K, Cao J, Lei D, Liu B, He M, Huang H. Toluene oxidation over mesoporous TiO 2 in a combined process of wet-scrubbing and UV-catalysis. CHEMOSPHERE 2020; 244:125567. [PMID: 31837565 DOI: 10.1016/j.chemosphere.2019.125567] [Citation(s) in RCA: 9] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/28/2019] [Revised: 11/28/2019] [Accepted: 12/06/2019] [Indexed: 06/10/2023]
Abstract
Toluene is a representative and toxic contaminant in industry or indoor airs. In this work, a novel and facile method was developed to prepare mesoporous TiO2 for the photo-catalytic oxidation of toluene in a wet-scrubbing reactor. Interestingly, by changing the preparation parameters, including dosage of template material, hydrolysis rate, hydrothermal temperature and calcination temperature, the crystalline phase of catalyst could be partially adjusted among brookite, anatase and rutile. With 30 ppm toluene input, an enhanced toluene removal of 62% and CO2 production of 95 ppm were achieved, while no soluble or particulate byproduct was released. In contrast to traditional photo-catalysis, the UV adsorbing ability of catalyst, the cluster of mesoporous TiO2 and the corresponding structure in micrometer-scale were key to the UV utilization and toluene removal in wet-scrubbing reactor.
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Affiliation(s)
- Yuxuan Zeng
- School of Environmental Science and Engineering, Sun Yat-Sen University, Guangzhou, China
| | - Yujie Zhan
- School of Environmental Science and Engineering, Sun Yat-Sen University, Guangzhou, China
| | - Ruijie Xie
- School of Environmental Science and Engineering, Sun Yat-Sen University, Guangzhou, China
| | - Kang Hu
- School of Environmental Science and Engineering, Sun Yat-Sen University, Guangzhou, China
| | - Jianping Cao
- School of Environmental Science and Engineering, Sun Yat-Sen University, Guangzhou, China
| | - Dongxue Lei
- School of Environmental Science and Engineering, Sun Yat-Sen University, Guangzhou, China
| | - Biyuan Liu
- School of Environmental Science and Engineering, Sun Yat-Sen University, Guangzhou, China
| | - Miao He
- School of Environmental Science and Engineering, Sun Yat-Sen University, Guangzhou, China
| | - Haibao Huang
- School of Environmental Science and Engineering, Sun Yat-Sen University, Guangzhou, China; Guangdong-Hong Kong Joint Research Center for Air Pollution Control, China.
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19
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Kinetic and Mechanistic Study of Rhodamine B Degradation by H2O2 and Cu/Al2O3/g-C3N4 Composite. Catalysts 2020. [DOI: 10.3390/catal10030317] [Citation(s) in RCA: 17] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022] Open
Abstract
The classic Fenton reaction, which is driven by iron species, has been widely explored for pollutant degradation, but is strictly limited to acidic conditions. In this work, a copper-based Fenton-like catalyst Cu/Al2O3/g-C3N4 was proposed that achieves high degradation efficiencies for Rhodamine B (Rh B) in a wide range of pH 4.9–11.0. The Cu/Al2O3 composite was first prepared via a hydrothermal method followed by a calcination process. The obtained Cu/Al2O3 composite was subsequently stabilized on graphitic carbon nitride (g-C3N4) by the formation of C−O−Cu bonds. The obtained composites were characterized through FT-IR, XRD, TEM, XPS, and N2 adsorption/desorption isotherms, and the immobilized Cu+ was proven to be active sites. The effects of Cu content, g-C3N4 content, H2O2 concentration, and pH on Rh B degradation were systematically investigated. The effect of the catalyst dose was confirmed with a specific reaction rate constant of (5.9 ± 0.07) × 10−9 m·s−1 and the activation energy was calculated to be 71.0 kJ/mol. In 100 min 96.4% of Rh B (initial concentration 20 mg/L, unadjusted pH (4.9)) was removed in the presence of 1 g/L of catalyst and 10 mM of H2O2 at 25 °C, with an observed reaction rate constant of 6.47 × 10−4 s−1. High degradation rates are achieved at neutral and alkaline conditions and a low copper leaching (0.55 mg/L) was observed even after four reaction cycles. Hydroxyl radical (HO·) was identified as the reactive oxygen species by using isopropanol as a radical scavenger and by ESR analysis. HPLC-MS revealed that the degradation of Rh B on Cu/Al2O3/CN composite involves N-de-ethylation, hydroxylation, de-carboxylation, chromophore cleavage, ring opening, and the mineralization process. Based on the results above, a tentative mechanism for the catalytic performance of the Cu/Al2O3/g-C3N4 composite was proposed. In summary, the characteristics of high degradation rate constants, low ion leaching, and the excellent applicability in neutral and alkaline conditions prove the Cu/Al2O3/g-C3N4 composite to be a superior Fenton-like catalyst compared to many conventional ones.
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20
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Sunlight active g-C3N4-based Mn+ (M Cu, Ni, Zn, Mn) – promoted catalysts: Sharing of nitrogen atoms as a door for optimizing photo-activity. MOLECULAR CATALYSIS 2020. [DOI: 10.1016/j.mcat.2019.110725] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 02/06/2023]
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21
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Synthesis of Z-scheme g-C3N4 nanosheets/Ag3PO4 photocatalysts with enhanced visible-light photocatalytic performance for the degradation of tetracycline and dye. CHINESE CHEM LETT 2020. [DOI: 10.1016/j.cclet.2019.05.029] [Citation(s) in RCA: 57] [Impact Index Per Article: 14.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/21/2023]
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22
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Chen H, Yue X, Yang J, Lv C, Dong S, Luo X, Sun Z, Zhang Y, Li B, Zhang F, Gu H, Yang Y, Zhang Q, Ge S, Bi H, Zheng D, Zhao Y, Li C, Peng W. Pyrolysis molecule of Torreya grandis bark for potential biomedicine. Saudi J Biol Sci 2019; 26:808-815. [PMID: 31049007 PMCID: PMC6486518 DOI: 10.1016/j.sjbs.2019.01.005] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/11/2018] [Revised: 01/07/2019] [Accepted: 01/08/2019] [Indexed: 11/27/2022] Open
Abstract
Torreya grandis is a unique tree species in China. Although full use has been made of the timber, the processing and utilization of the bark has not been effective. In order to explore a new way to utilize the bark of Torreya grandis, a powder of T. grandis bark was prepared and analyzed qualitatively and quantitatively. Differential scanning calorimetry (TG) and pyrolysis gas chromatography-mass spectrometry (PY-GC/MS) revealed many bioactive components in the bark of T. grandis, such as acetic acid, 2-methoxy-4-vinyl phenol, D-mannose, and furfural. These substances have potential broad applications in the chemical industry, biomedicine, and food additives. The chemical constituents of the bark of T. grandis suggest a theoretical basis for the future development and utilization of the bark of T. grandis.
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Affiliation(s)
- Huiling Chen
- School of Forestry, Henan Agricultural University, Zhengzhou 450002, China
| | - Xiaochen Yue
- School of Forestry, Henan Agricultural University, Zhengzhou 450002, China
| | - Jun Yang
- School of Forestry, Henan Agricultural University, Zhengzhou 450002, China
| | - Chunxia Lv
- The Scientific Research Institution, Henan Xiaoqinling National Nature Reserve Administration Bureau, Sanmenxia 472500, China
| | - Shuaiwei Dong
- The Scientific Research Institution, Henan Xiaoqinling National Nature Reserve Administration Bureau, Sanmenxia 472500, China
| | - Xuefeng Luo
- The Scientific Research Institution, Henan Xiaoqinling National Nature Reserve Administration Bureau, Sanmenxia 472500, China
| | - Zhiyong Sun
- The Scientific Research Institution, Henan Xiaoqinling National Nature Reserve Administration Bureau, Sanmenxia 472500, China
| | - Ying Zhang
- The Scientific Research Institution, Henan Xiaoqinling National Nature Reserve Administration Bureau, Sanmenxia 472500, China
| | - Baoxiang Li
- The Scientific Research Institution, Henan Xiaoqinling National Nature Reserve Administration Bureau, Sanmenxia 472500, China
| | - Faping Zhang
- The Scientific Research Institution, Henan Xiaoqinling National Nature Reserve Administration Bureau, Sanmenxia 472500, China
| | - Haiping Gu
- School of Forestry, Henan Agricultural University, Zhengzhou 450002, China
| | - Yafeng Yang
- School of Forestry, Henan Agricultural University, Zhengzhou 450002, China
| | - Qiuling Zhang
- School of Forestry, Henan Agricultural University, Zhengzhou 450002, China
| | - Shengbo Ge
- Department of Mechanical and Energy Engineering, University of North Texas, Denton, TX 76203, USA
| | - Huitao Bi
- School of Forestry, Henan Agricultural University, Zhengzhou 450002, China
| | - Dongfang Zheng
- School of Forestry, Henan Agricultural University, Zhengzhou 450002, China
| | - Yong Zhao
- School of Forestry, Henan Agricultural University, Zhengzhou 450002, China
| | - Cheng Li
- School of Forestry, Henan Agricultural University, Zhengzhou 450002, China
| | - Wanxi Peng
- School of Forestry, Henan Agricultural University, Zhengzhou 450002, China
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23
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Liu SH, Lin WX. A simple method to prepare g-C 3N 4-TiO 2/waste zeolites as visible-light-responsive photocatalytic coatings for degradation of indoor formaldehyde. JOURNAL OF HAZARDOUS MATERIALS 2019; 368:468-476. [PMID: 30710775 DOI: 10.1016/j.jhazmat.2019.01.082] [Citation(s) in RCA: 31] [Impact Index Per Article: 6.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/30/2018] [Revised: 01/08/2019] [Accepted: 01/23/2019] [Indexed: 06/09/2023]
Abstract
The indoor air quality should be highly addressed because people spend more time staying in indoor environments. Photocatalytic degradation of indoor pollutants (e.g., formaldehyde) is one of the most promising and environmental friendly technologies. In this work, a heterostructured photocatalyst combining graphitic carbon nitride (g-C3N4), TiO2 and waste zeolites (g-C3N4-TiO2/waste zeolites) is developed by a facile calcination and sol-gel method. The prepared photocatalysts exhibit the superior visible-light-responsive activities toward formaldehyde degradation (k = 0.0127 min-1) which is higher than g-C3N4-TiO2 (k = 0.0123 min-1) and P25 (k = 0.0056 min-1). Over 90% of low-concentration formaldehyde can be oxidized by g-C3N4-TiO2/waste zeolites under a commercial LED light within 300 min. The electron spin resonance spectra indicate that the superoxide radical anions (O2-) photogenerated on the g-C3N4-TiO2/waste zeolites under visible light irradiation are responsible for the decomposition of formaldehyde. The enhancement in the photocatalytic decomposition of formaldehyde in the air is possibly due to the heterojunction between g-C3N4 (the enhanced absorption of visible light) and TiO2 (fast transfer of photogenerated electrons from g-C3N4) as well as assisted adsorption of gas-phase formaldehyde via waste zeolites. This work also exemplifies the valorization of industrial silicate wastes to efficient photocatalytic coatings for indoor air purification.
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Affiliation(s)
- Shou-Heng Liu
- Department of Environmental Engineering, National Cheng Kung University, Tainan 70101, Taiwan.
| | - Wei-Xing Lin
- Department of Environmental Engineering, National Cheng Kung University, Tainan 70101, Taiwan
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