JOURNAL OF HAZARDOUS MATERIALS
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2022
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IF 14.224
Yadan Guo,Shuaihang Li,Fan Yang,Chenxi Li,Yaoping Guo,Keng Xuan,Guanghui Wang,Yunhai Liu,Jun Li
Photocatalytic reduction of U(VI) in aqueous solutions has been considered as an efficient and promising technology to solve radioactive U pollution. In this work, density functional theory (DFT) calculations were firstly employed to optimize and compare the adsorption configurations combined uranium with four given photocatalysts , then their adsorption energies were − 0.97 eV for AgFeO 2 , − 1.15 eV for Zn doped AgFeO 2 , − 1.73 eV for Cu doped AgFeO 2 and − 2.66 eV for S doped AgFeO 2 , respectively, indicating the sulfur doping plays a major role in U(VI) photoreduction . Herein, a visible light responsive efficient sulfur doped AgFeO 2 photocatalyst (S doped AgFeO 2 ) was synthesized and utilized to photocatalytic reduction of U(VI) in aqueous solutions. According to XRD , XPS and TEM analysis, the sulfur was successfully doped in AgFeO 2 via the hydrothermal method . The batch experimental showed that S doping enhanced the U(VI) photoreduction activity of AgFeO 2 , and the S-AFO-3 photocatalyst exhibited the highest photocatalytic activity (92.57%), which was 1.5 times than that of pure AgFeO 2 . ESR , PL and DFT results demonstrated that the enhancement of adsorbed U(VI) photoreduction was attributed to the own unique effect of oxygen vacancy defects and efficient charge separation of S doped AgFeO 2 photocatalyst. Due to its higher adsorption energies, fast-U(VI) photoreduction rate and superior chemical stability, the sulfur doped AgFeO 2 photocatalyst is hoped for water remediation containing U(VI) wastewater.
研究领域:
环境科学
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材料科学
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DOI
高影响因子
CHEMICAL ENGINEERING JOURNAL
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2021
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IF 13.273
Chenxi Li,Yadan Guo,Dandan Tang,Yaoping Guo,Guanghui Wang,Hao Jiang,Jun Li
The density functional theory (DFT) not only is indispensable to calculate the electronic structure and chemical property of photocatalysts, but also provides guidance to the understanding of the mechanisms involved in photocatalysis. Herein, a novel Zn doped AgFeO 2 was successfully constructed for enhancement of Cr(VI) reduction and azophloxine decomposition under visible light irradiation. The DFT calculation was employed to set up a Zn doped AgFeO 2 model to simulate its split Zn 3 d levels shift to lower energy to optimize the band structure. With Zn doped, the AgFeO 2 exhibit enhanced reducing capacity. As expected, compared to unmodified AgFeO 2 , Zn doped AgFeO 2 can reduce and remove more than 90% of Cr(VI). Based on theoretical analysis and systematic experiments, the enhanced photocatalytic of Zn doped AgFeO 2 were arisen from superoxide radical (O 2 − ) generation and photocarrier transfer via oxygen vacancies (OVs) enrichment, and the OVs would provide coordinatively unsaturated sites for Cr(VI) adsorption. We expect this work can provide new insights into the photocatalytic utilization of AgFeO 2 .
研究领域:
材料科学
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环境科学
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理论化学
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产品关联
DOI
高影响因子
COLLOIDS AND SURFACES A-PHYSICOCHEMICAL AND ENGINEERING ASPECTS
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2022
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IF 5.518
Jinge Du,Shuanglong Ma,Na Zhang,Wenjing Liu,Mengdi Lv,Tianjun Ni,Zhen An,Kai Li,Yichun Bai
A novel porous Z-scheme Ag/AgFeO 2 /g-C 3 N 4 (AAF/UPCN) photocatalyst was successfully prepared via a facile hydrothermal, precipitation and photo-deposition–method. Under visible light irradiation, AAF/UPCN exhibited excellent bisphenol A degradation effect and Staphylococcus aureus inactivation effect compared with porous g-C 3 N 4 (UPCN) and AgFeO 2 . The •O 2 ‾ was the major active species during the photocatalytic degradation process. For the photocatalytic mechanism, the photoexcited electrons of UPCN transferred to AgFeO 2 mediated by Ag nanoparticles . This charge migration and separation route was verified collectively by the PL spectra, photoelectrochemical characterizations, chemical scavenger experiments and ESR measurements. Furthermore, the band distribution of catalysts was obtained by DFT calculation. This Ag nanoparticles mediated electron transfer pathway could promote the effective segregation of photoexcited carriers. The synergistic effect of UPCN, AgFeO 2 and Ag in heterostructure could promote the efficient separation of photogenerated charge carriers. This study provides a new strategy for rational design of high-efficient g-C 3 N 4 -based photocatalysts for environmental remediation.
研究领域:
环境科学
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材料科学
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DOI
高影响因子
JOURNAL OF ALLOYS AND COMPOUNDS
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2022
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IF 6.371
Yanyan Cui,Ping Zhang,Mengke Li,Chengcheng Lin,Yaling Wang
Photocatalysis technology is considered an effective way to solve the problem of water pollution and energy shortage, and is hinged on the development of the photocatalyst . In this study, p-type semiconductor AgFeO 2 and the n-type photocatalyst Ag 3 VO 4 formed a p-n junction via a simple hydrothermal method . Compared with pure Ag 3 VO 4 , the 4 % AgFeO 2 -modified Ag 3 VO 4 photocatalyst (AgVFe-4) exhibited the best photocatalytic activity: the photodegradation rate of RhB reached 95.1 % within 60 min and possessed good photostability under UV–visible light irradiation. The physical and chemical properties of AgVFe-4 indicated that the composite structure showed a larger special surface area, much lower intensity of photoluminescence , and higher photogenerated carriers separation efficiency. The p-type AgFeO 2 and n-type Ag 3 VO 4 could form the p-n junction structure. Based on the analysis of reactive agents, the h + , •O 2 − and •OH were the main active species during organic pollutions photodegradation, and the photocatalysis process followed the Z-scheme mechanism. Meanwhile, some silver element in the photocatalyst was reduced into Ag 0 , which could act as the recombination center of the photogenerated carriers, further improving the photocatalytic performance. This work may arouse an increasing interest in designing more Z-scheme silver-based p-n junction heterojunction photocatalysts.
研究领域:
环境科学
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材料科学
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产品关联
DOI
高影响因子
Journal of the Taiwan Institute of Chemical Engineers
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2023
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IF 5.7
Zhixin Chen,Boyuan Ning,Yanqing Cai,Minghua Liu,Pingfan Xu,Peikun Zhang,Guangcan Xiao,Yunhui He
Background The accumulation of antibiotics in water systems has received considerable global attention due to its detrimental effects. There is an urgent need to develop rapid and efficient methods for the degradation of antibiotics. Methods In this work, a highly efficient AgFeO 2 /Ag 3 VO 4 photocatalyst was successfully fabricated by a hydrothermal method and analyzed using different techniques. Under visible light irradiation, photocatalytic behavior of AgFeO 2 /Ag 3 VO 4 heterojunctions in the degradation of levofloxacin is investigated. Significant findings The results showed that p-n heterojunction was formed between AgFeO 2 and Ag 3 VO 4 , which improved the separation and transfer of photogenerated charge carrier under the action of the internal electric field. The apparent reaction rate of AgFeO 2 /Ag 3 VO 4 heterostructure toward degradation of levofloxacin reached to 0.2770 min −1 , which was about 2.15 times and 36.73 times larger than those of Ag 3 VO 4 and AgFeO 2 , respectively, and much larger than other counterparts. Furthermore, possible photocatalytic degradation pathway of levofloxacin was comprehensively determined by LC-MS analysis. This work would provide in-depth understanding on the efficient photocatalytic removal of antibiotics for sustainable environmental remediation.
研究领域:
环境科学
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材料科学
✓ 已验证
产品关联
DOI
高影响因子
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