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Zhang N, Zhang B, Wang C, Sui H, Zhang N, Wen Z, He A, Zhang R, Xue R. Magnetic CoFe hydrotalcite composite Co metal-organic framework material efficiently activating peroxymonosulfate to degrade sulfamethoxazole: Oxygen vacancy-mediated radical and non-radical pathways. J Colloid Interface Sci 2024; 671:110-123. [PMID: 38795532 DOI: 10.1016/j.jcis.2024.05.166] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/26/2024] [Revised: 05/15/2024] [Accepted: 05/22/2024] [Indexed: 05/28/2024]
Abstract
Herein, a novel rich oxygen vacancy (Ov) cobalt-iron hydrotalcite composite cobalt metal-organic framework material (ZIF-67/CoFe-LDH) was prepared by simple urea water and heat reduction approach and utilized for the peroxymonosulfate (PMS) system to remove sulfamethoxazole (SMX). 95 ± 1.32 % SMX (20 mg/L) was able to degraded in 20 min with TOC removal of 53 ± 1.56 % in ZIF-67/CoFe-LDH/PMS system. The system maintained a fantastic catalytic capability with wide pH range (3-9) and common interfering substances (Cl-, NO3-, CO32-, PO42- and humic acid (HA)), and the degradation efficiency could even remain 80.2 ± 1.48 % at the fifth cycle. Meanwhile, the applicability and feasibility of the catalysts for practical water treatment was verified by the degradation effects of SMX in different water environments and several other typical pollutants. Co and Fe bimetallic active centers synergistically activate PMS, and density functional theory (DFT) predicted adsorption energy about Ov in ZIF-67/CoFe-LDH for PMS was 1.335 eV, and OO bond length of PMS was stretched to 1.826 Å. As a result, PMS was more easily activated and broken, which accelerated the singlet oxygen (1O2), sulfate radical (SO4•-), high-valent metals and other reactive oxygen species (ROS). Radical and non-radical jointly degrading the pollutants improved the catalytic effect. Finally, SMX degradation intermediates were analyzed to explain the degradation pathway and their biotoxicity was also evaluated. This paper provides a new research perspective of oxygen vacancy activating PMS to degrade pollutants.
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Affiliation(s)
- Nianbo Zhang
- College of Environmental Science and Engineering, Qilu University of Technology (Shandong Academy of Science), 3501 University Road, Jinan 250353, China
| | - Baoyong Zhang
- Key Laboratory of Industrial Ecology and Environmental Engineering (Ministry of Education, China), School of Environmental Science and Technology, Dalian University of Technology, Dalian 116024, China
| | - Chen Wang
- College of Environmental Science and Engineering, Qilu University of Technology (Shandong Academy of Science), 3501 University Road, Jinan 250353, China
| | - Huiying Sui
- College of Environmental Science and Engineering, Qilu University of Technology (Shandong Academy of Science), 3501 University Road, Jinan 250353, China
| | - Na Zhang
- College of Environmental Science and Engineering, Qilu University of Technology (Shandong Academy of Science), 3501 University Road, Jinan 250353, China
| | - Zunqing Wen
- College of Environmental Science and Engineering, Qilu University of Technology (Shandong Academy of Science), 3501 University Road, Jinan 250353, China
| | - Ao He
- College of Environmental Science and Engineering, Qilu University of Technology (Shandong Academy of Science), 3501 University Road, Jinan 250353, China
| | - Ruiyan Zhang
- College of Environmental Science and Engineering, Qilu University of Technology (Shandong Academy of Science), 3501 University Road, Jinan 250353, China
| | - Rong Xue
- College of Environmental Science and Engineering, Qilu University of Technology (Shandong Academy of Science), 3501 University Road, Jinan 250353, China.
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Li W, Jiang H, Zhang X, Lei B, Li L, Zhou H, Zhong M. Sustainable Electrosynthesis of N,N-Dimethylformamide via Relay Catalysis on Synergistic Active Sites. J Am Chem Soc 2024; 146:21968-21976. [PMID: 39052048 DOI: 10.1021/jacs.4c07142] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 07/27/2024]
Abstract
Electrified synthesis of high-value organonitrogen chemicals from low-cost carbon- and nitrogen-based feedstocks offers an economically and environmentally appealing alternative to traditional thermocatalytic methods. However, the intricate electrochemical reactions at electrode surfaces pose significant challenges in controlling selectivity and activity, especially for producing complex substances such as N,N-dimethylformamide (DMF). Herein, we tackle this challenge by developing relay catalysis for efficient DMF production using a composite WO2-NiOOH/Ni catalyst with two distinctive active sites. Specifically, WO2 selectively promotes dimethylamine (DMA) electrooxidation to produce strongly surface-bound (CH3)2N*, while nearby NiOOH facilitates methanol electrooxidation to yield more weakly bound *CHO. The disparity in binding energetics of the key C- and N-intermediates expedites C-N coupling at the WO2-NiOOH interface. In situ infrared spectroscopy with isotope-labeling experiments, quasi-in situ electron paramagnetic resonance trapping experiments, and electrochemical operating experiments revealed the C-N coupling mechanism and enhanced DMF-synthesis selectivity and activity. In situ X-ray absorption spectroscopy (XAS) and postreaction transmission electron microscopy (TEM) studies verified the stability of WO2-NiOOH/Ni during extended electrochemical operation. A Faradaic efficiency of ∼50% and a production rate of 438 μmol cm-2 h-1 were achieved at an industrially relevant current density of 100 mA cm-2 over an 80 h DMF production period. This study introduces a new paradigm for developing electrothermo relay catalysis for the sustainable and efficient synthesis of valuable organic chemicals with industrial potential.
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Affiliation(s)
- Weihang Li
- College of Engineering and Applied Sciences, Collaborative Innovation Centre of Advanced Microstructures, National Laboratory of Solid State Microstructures, Frontiers Science Center for Critical Earth Material Cycling, Nanjing University, 163 Xianlin Avenue, Qixia District, Nanjing 210023, China
| | - Haoyang Jiang
- College of Engineering and Applied Sciences, Collaborative Innovation Centre of Advanced Microstructures, National Laboratory of Solid State Microstructures, Frontiers Science Center for Critical Earth Material Cycling, Nanjing University, 163 Xianlin Avenue, Qixia District, Nanjing 210023, China
| | - Xiang Zhang
- College of Engineering and Applied Sciences, Collaborative Innovation Centre of Advanced Microstructures, National Laboratory of Solid State Microstructures, Frontiers Science Center for Critical Earth Material Cycling, Nanjing University, 163 Xianlin Avenue, Qixia District, Nanjing 210023, China
| | - Bo Lei
- College of Engineering and Applied Sciences, Collaborative Innovation Centre of Advanced Microstructures, National Laboratory of Solid State Microstructures, Frontiers Science Center for Critical Earth Material Cycling, Nanjing University, 163 Xianlin Avenue, Qixia District, Nanjing 210023, China
| | - Le Li
- College of Engineering and Applied Sciences, Collaborative Innovation Centre of Advanced Microstructures, National Laboratory of Solid State Microstructures, Frontiers Science Center for Critical Earth Material Cycling, Nanjing University, 163 Xianlin Avenue, Qixia District, Nanjing 210023, China
| | - Haoshen Zhou
- College of Engineering and Applied Sciences, Collaborative Innovation Centre of Advanced Microstructures, National Laboratory of Solid State Microstructures, Frontiers Science Center for Critical Earth Material Cycling, Nanjing University, 163 Xianlin Avenue, Qixia District, Nanjing 210023, China
| | - Miao Zhong
- College of Engineering and Applied Sciences, Collaborative Innovation Centre of Advanced Microstructures, National Laboratory of Solid State Microstructures, Frontiers Science Center for Critical Earth Material Cycling, Nanjing University, 163 Xianlin Avenue, Qixia District, Nanjing 210023, China
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3
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Zhang G, Wu T, Yu W, Li J, Wang Y, Wang J, Liu S, Chang B, Liu X, Zhou W. Laser regulated mixed-phase TiO 2 for electrochemical overall nitrogen fixation. J Colloid Interface Sci 2024; 674:168-177. [PMID: 38925062 DOI: 10.1016/j.jcis.2024.06.016] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/11/2024] [Revised: 05/09/2024] [Accepted: 06/03/2024] [Indexed: 06/28/2024]
Abstract
Traditional oxide electrocatalytic materials encounter significant challenges associated with sluggish reaction kinetics and formidable energy barriers for NH intermediates formation in electrocatalytic nitrogen fixation. The implementation of phase control emerges as an effective strategy to address these challenges. Herein, leveraging the energy localization of laser, this work achieved precise phase control of TiO2. In the optimized material system, the rutile phase TiO2 facilitates nitrogen adsorption, while the anatase phase TiO2 provides proton sources and active oxygen species. The synergistic effect of the two phases effectively enhances the electrocatalytic activity for nitrogen reduction and oxidation, with an ammonia yield reaching ∼22.3 μg h-1 cm-2 and a nitrate yield reaching ∼60.9 μg h-1 cm-2. Furthermore, a coupled dual-electrode system with mixed-phase titanium dioxide as both the anode and cathode successfully achieved a breakthrough in electrochemical overall nitrogen fixation. This laser precision control strategy for manipulating phase sites lays the groundwork for designing efficient catalysts for energy conversion and even energy storage nanomaterials.
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Affiliation(s)
- Guixiang Zhang
- Institute for Advanced Interdisciplinary Research (IAIR), School of Chemistry and Chemical Engineering, University of Jinan, Jinan, 250022, PR China
| | - Tong Wu
- Institute for Advanced Interdisciplinary Research (IAIR), School of Chemistry and Chemical Engineering, University of Jinan, Jinan, 250022, PR China
| | - Wanqiang Yu
- Institute for Advanced Interdisciplinary Research (IAIR), School of Chemistry and Chemical Engineering, University of Jinan, Jinan, 250022, PR China
| | - Jiawei Li
- Institute for Advanced Interdisciplinary Research (IAIR), School of Chemistry and Chemical Engineering, University of Jinan, Jinan, 250022, PR China
| | - Yujie Wang
- Institute for Advanced Interdisciplinary Research (IAIR), School of Chemistry and Chemical Engineering, University of Jinan, Jinan, 250022, PR China
| | - Junjian Wang
- Institute for Advanced Interdisciplinary Research (IAIR), School of Chemistry and Chemical Engineering, University of Jinan, Jinan, 250022, PR China
| | - Shunyao Liu
- Institute for Advanced Interdisciplinary Research (IAIR), School of Chemistry and Chemical Engineering, University of Jinan, Jinan, 250022, PR China
| | - Bin Chang
- KAUST Catalysis Center (KCC), Division of Physical Science and Engineering, King Abdullah University of Science and Technology (KAUST), Thuwal 23955-6900, Saudi Arabia.
| | - Xiaoyan Liu
- Institute for Advanced Interdisciplinary Research (IAIR), School of Chemistry and Chemical Engineering, University of Jinan, Jinan, 250022, PR China.
| | - Weijia Zhou
- Institute for Advanced Interdisciplinary Research (IAIR), School of Chemistry and Chemical Engineering, University of Jinan, Jinan, 250022, PR China.
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Hou Y, Fu Q, Zhong H, Yu J, Tao Y, Gong Z, Li J, Wei S, Qiu J, Wang J, Zhu F, Ouyang G. High-performance plastic-derived metal-free catalysts for organic pollutants degradation via Fenton-like reaction. THE SCIENCE OF THE TOTAL ENVIRONMENT 2024; 916:170185. [PMID: 38244619 DOI: 10.1016/j.scitotenv.2024.170185] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/24/2023] [Revised: 01/07/2024] [Accepted: 01/13/2024] [Indexed: 01/22/2024]
Abstract
The preparation of waste plastics-derived catalysts is an effective strategy for the waste reclamation. However, plastic-derived material is unsuitable for wastewater purification due to its small specific surface area (SSA) and inadequate active sites (such as N/O sites). Herein, we synthesized graphene-like nanosheets using g-C3N4 as the self-sacrificing soft template and plastic as the carbon precursor. Consequently, this strategy greatly promoted the efficiencies of the emerging organic pollutants degradation with the SSA and N content of the plastic-derived biochar increasing up to 1043.4 m2/g and 17.53 at.%, respectively. In detail, 100 % sulfadiazine (SD) removal could be achieved in 180 s via the activation of peroxymonosulfate (PMS) and the catalytic activity is far higher than previous research. Mechanism experiments corroborated that such a striking performance was attributed to the generation of SO4•-, O2•- and 1O2. Meanwhile, kinds of plastic precursors, even medical waste (i.e., masks, gauze, operating caps and degreasing cotton) were also applicable. And the practical application of the plastic-derived catalyst was further demonstrated by treating pollutants in a continuous flow mode with in situ fabricated membrane. This work provides valuable insights into waste plastics processing and water pollutants removal.
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Affiliation(s)
- Yu Hou
- MOE Key Laboratory of Bioinorganic and Synthetic Chemistry/KLGHEI of Environment and Energy Chemistry, School of Chemistry, Sun Yat-Sen University, Guangzhou 510275, China
| | - Qi Fu
- MOE Key Laboratory of Bioinorganic and Synthetic Chemistry/KLGHEI of Environment and Energy Chemistry, School of Chemistry, Sun Yat-Sen University, Guangzhou 510275, China
| | - Huajie Zhong
- School of Chemical Engineering and Technology, Sun Yat-Sen University, Zhuhai 519087, China
| | - Jiaxing Yu
- MOE Key Laboratory of Bioinorganic and Synthetic Chemistry/KLGHEI of Environment and Energy Chemistry, School of Chemistry, Sun Yat-Sen University, Guangzhou 510275, China
| | - Yuan Tao
- MOE Key Laboratory of Bioinorganic and Synthetic Chemistry/KLGHEI of Environment and Energy Chemistry, School of Chemistry, Sun Yat-Sen University, Guangzhou 510275, China
| | - Zeyu Gong
- School of Chemical Engineering and Technology, Sun Yat-Sen University, Zhuhai 519087, China
| | - Jianqiang Li
- JiangXi ZhengPuYiHe Technology Co. Ltd, Nanchang 330000, China
| | - Songbo Wei
- Department of Chemistry, University of California, Riverside, CA 92521, USA
| | - Junlang Qiu
- School of Environmental Science and Engineering, Sun Yat-Sen University, Guangzhou 510275, China
| | - Junhui Wang
- School of Chemical Engineering and Technology, Sun Yat-Sen University, Zhuhai 519087, China.
| | - Fang Zhu
- MOE Key Laboratory of Bioinorganic and Synthetic Chemistry/KLGHEI of Environment and Energy Chemistry, School of Chemistry, Sun Yat-Sen University, Guangzhou 510275, China
| | - Gangfeng Ouyang
- MOE Key Laboratory of Bioinorganic and Synthetic Chemistry/KLGHEI of Environment and Energy Chemistry, School of Chemistry, Sun Yat-Sen University, Guangzhou 510275, China; School of Chemical Engineering and Technology, Sun Yat-Sen University, Zhuhai 519087, China; Guangdong Provincial Key Laboratory of Emergency Test for Dangerous Chemicals, Guangdong Institute of Analysis (China National Analytical Center Guangzhou), Guangdong Academy of Science, 100 Xianlie Middle Road, Guangzhou 510070, China
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Guo C, Tao C, Yu F, Zhao Z, Wang Z, Deng N, Huang X. Ball-milled layer double hydroxide as persulfate activator for efficient degradation of organic: Alkaline sites-triggered non-radical mechanism. JOURNAL OF HAZARDOUS MATERIALS 2024; 461:132219. [PMID: 37722323 DOI: 10.1016/j.jhazmat.2023.132219] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/05/2023] [Revised: 08/01/2023] [Accepted: 08/02/2023] [Indexed: 09/20/2023]
Abstract
Considerable efforts have been put into enhancing the activation performance of peroxydisulfate (PDS) by catalysts toward oxidative degradation of organic pollutants, while the oxidative selectivity is somehow overlooked. Here, we reported an enhanced non-radical oxidation pathway of PDS, activated by ball-milled Mg/Al-layered double hydroxide (BM-LDH), to reconcile the selectivity and reactivity. EPR and quenching experiments suggested that 1O2 dominated the oxidative pathway for phenol degradation without generating carcinogenic halide by-products. Multiple interfacial characterizations and density functional theory (DFT) calculations revealed that BM-LDH played dual roles in PDS activation: (1) the interlaminar BM-LDH allowed PDS intercalation to form complexed PDS, resulting in decreases in the activation barrier of PDS; (2) abundant terminal hydroxyls in the layers of BM-LDH acted as alkaline-activation sites that can efficiently activate PDS to generate 1O2 toward phenol degradation. Ball-milling treatment of LDH refined the structural hierarchy of LDH to create pore volumes, which greatly enhanced the diffusion of phenol to the intercalated PDS, resulting in more than twice the reaction rate for phenol degradation. This study provided a promising approach to simultaneously control over the reactivity and selectivity toward PDS activation that are critical for the degradation of organic pollutants particularly in drinking water treatment.
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Affiliation(s)
- Changjin Guo
- School of Environmental and Chemical Engineering, Shanghai University, Shanghai 200444, China
| | - Chen Tao
- School of Environmental and Chemical Engineering, Shanghai University, Shanghai 200444, China
| | - Fang Yu
- School of Environmental and Chemical Engineering, Shanghai University, Shanghai 200444, China
| | - Zhenzhen Zhao
- School of Environmental and Chemical Engineering, Shanghai University, Shanghai 200444, China
| | - Zhiquan Wang
- School of Life and Environmental Science, Wenzhou University, Wenzhou, Zhejiang 325035, China
| | - Ning Deng
- School of Environmental and Chemical Engineering, Shanghai University, Shanghai 200444, China.
| | - Xin Huang
- School of Environmental and Chemical Engineering, Shanghai University, Shanghai 200444, China.
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Chen S, Li Z, Wu L, Liu L, Hu J, Hou H, Liang S, Yang J. Generation of high-valent iron-oxo porphyrin cation radicals on hemin loaded carbon nanotubes for efficient degradation of sulfathiazole. JOURNAL OF HAZARDOUS MATERIALS 2023; 444:130402. [PMID: 36403452 DOI: 10.1016/j.jhazmat.2022.130402] [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: 10/19/2022] [Revised: 11/08/2022] [Accepted: 11/12/2022] [Indexed: 06/16/2023]
Abstract
Hemin has attracted considerable interest as an efficient catalyst recently, however, its direct application is inefficient due to severe molecular aggregation. Immobilizing hemin on various supports is a feasible approach to address this issue. In this work, a CNTs-hemin catalyst was prepared by loading hemin onto multiwalled carbon nanotubes (CNTs) through ball milling. Compared with hemin, CNTs-hemin demonstrates remarkably enhanced performance in the peroxymonosulfate system, with a 650-fold improvement of apparent rate constant, reaching 97.8% degradation of sulfathiazole in 5 min. High-valent iron-oxo porphyrin cation ((Porp)+•FeIV=O) radicals are proposed as the dominant reactive species in the CNTs-hemin/peroxymonosulfate system instead of sulfate radicals (SO4•-), hydroxyl radicals (•OH), superoxide radicals (O2•-) and singlet oxygen (1O2). More in-depth mechanisms reveal that the strong electron transfer between CNTs and hemin promotes the generation of (Porp)+•FeIV=O radicals through a heterolysis pathway. This research enriches the understanding of the catalytic mechanism of supported biomimetic catalysts for PMS activation and provides a perspective on the role of support materials for catalytic activity.
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Affiliation(s)
- Sijing Chen
- School of Environmental Science and Engineering, Huazhong University of Science and Technology (HUST), Wuhan, Hubei 430074, China; Hubei Provincial Engineering Laboratory of Solid Waste Treatment, Disposal and Recycling, Huazhong University of Science and Technology (HUST), Wuhan, Hubei 430074, China
| | - Zhen Li
- School of Environmental Science and Engineering, Huazhong University of Science and Technology (HUST), Wuhan, Hubei 430074, China; Hubei Provincial Engineering Laboratory of Solid Waste Treatment, Disposal and Recycling, Huazhong University of Science and Technology (HUST), Wuhan, Hubei 430074, China
| | - Longsheng Wu
- School of Environmental Science and Engineering, Huazhong University of Science and Technology (HUST), Wuhan, Hubei 430074, China; Hubei Provincial Engineering Laboratory of Solid Waste Treatment, Disposal and Recycling, Huazhong University of Science and Technology (HUST), Wuhan, Hubei 430074, China
| | - Lu Liu
- School of Environmental Science and Engineering, Huazhong University of Science and Technology (HUST), Wuhan, Hubei 430074, China; Hubei Provincial Engineering Laboratory of Solid Waste Treatment, Disposal and Recycling, Huazhong University of Science and Technology (HUST), Wuhan, Hubei 430074, China
| | - Jingping Hu
- School of Environmental Science and Engineering, Huazhong University of Science and Technology (HUST), Wuhan, Hubei 430074, China; Hubei Provincial Engineering Laboratory of Solid Waste Treatment, Disposal and Recycling, Huazhong University of Science and Technology (HUST), Wuhan, Hubei 430074, China; State Key Laboratory of Coal Combustion, Huazhong University of Science and Technology (HUST), Wuhan, Hubei 430074, China.
| | - Huijie Hou
- School of Environmental Science and Engineering, Huazhong University of Science and Technology (HUST), Wuhan, Hubei 430074, China; Hubei Provincial Engineering Laboratory of Solid Waste Treatment, Disposal and Recycling, Huazhong University of Science and Technology (HUST), Wuhan, Hubei 430074, China
| | - Sha Liang
- School of Environmental Science and Engineering, Huazhong University of Science and Technology (HUST), Wuhan, Hubei 430074, China; Hubei Provincial Engineering Laboratory of Solid Waste Treatment, Disposal and Recycling, Huazhong University of Science and Technology (HUST), Wuhan, Hubei 430074, China
| | - Jiakuan Yang
- School of Environmental Science and Engineering, Huazhong University of Science and Technology (HUST), Wuhan, Hubei 430074, China; Hubei Provincial Engineering Laboratory of Solid Waste Treatment, Disposal and Recycling, Huazhong University of Science and Technology (HUST), Wuhan, Hubei 430074, China; State Key Laboratory of Coal Combustion, Huazhong University of Science and Technology (HUST), Wuhan, Hubei 430074, China
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Electrospinning of n-hemin/PAN Nanocomposite Membranes and Its Photo-Enhanced Enzyme-like Catalysis. Polymers (Basel) 2022; 14:polym14235135. [PMID: 36501529 PMCID: PMC9736454 DOI: 10.3390/polym14235135] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/29/2022] [Revised: 11/19/2022] [Accepted: 11/21/2022] [Indexed: 11/30/2022] Open
Abstract
Hemin possesses great potential in eliminating organic pollutants due to its mild reaction condition, light-harvesting efficiency, and environmental friendliness. However, it has drawbacks such as being easy to aggregate and hard to recycle, and poor stability should be improved in practical application. Herein, the subject developed an electrospinning approach to enable the hemin particulates to be immobilized onto polyacrylonitrile (PAN) nanofibers stably. Hydrogen peroxide (H2O2) was adopted as an oxidant in the system to simulate the enzymatic catalysis of hemin in an organism. Scanning electron microscopy (SEM), Fourier transform infrared spectroscopy (FTIR), X-ray photoelectron spectroscopy (XPS), UV-Vis diffuse reflection spectroscopy (DRS), and electron spin resonance spectroscopy (ESR) analysis was employed to discuss the morphology, structure, and mechanism of the prepared n-hemin/PAN nanocomposite membranes, and 0.02 mmol L-1 of the rhodamine B (RhB) removal activity in different conditions was also verified with these membranes. The kinetic studies showed that n-hemin/PAN nanocomposite membranes maintained excellent properties both in adsorption and degradation. Around 42% RhB could be adsorbed in the dark, while 91% RhB decolorized under xenon lamp irradiation in 110 min, suggesting the catalytic performance of n-hemin/PAN was greatly driven by light irradiation. Differing from the axial coordinated hemin complexes, n-hemin/PAN would catalyze hydrogen peroxide into •OH radicals rather than •OOH and high-valent metal-oxo species. This work provides an effective way to support hemin as nanocomposite membranes, in which the molecular interaction between polymer and hemin made their light adsorption an obvious red shift.
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