Journal of Physical Chemistry C
·
2021
·
IF 4.126
Dai Sun,Yu-Le Wang,Peng-Yue Zhu,Hai-Tao Ren,Yong Liu,Song-Hai Wu,Shao-Yi Jia,Xu Han
Mechanisms involved in the photocatalytic oxidation of As(III) are complicated in that various oxidizing species (such as h+, •OH, and O2•–) have been suggested to play important roles in different photocatalytic systems. In this study, Bi2.15WO6 shows high reactivity in the photocatalytic oxidation of As(III) under visible light. Quenching experiments indicate that apart from h+, the surface superoxo (≡Bi–OO•) and peroxo species (≡Bi–OOH) formed on Bi2.15WO6 also contribute to As(III) oxidation. The increased production of H2O2 with increasingly consumed As(III) or with the addition of H-donors such as glucose and various phenolics further reveals that H-abstraction from As(III) or H-donors to ≡Bi–OO• and then to ≡Bi–OOH is an important pathway involved in H2O2 production and As(III) oxidation. In addition, various characterizations confirm that the As(III)–O–Bi(III) surface complexes formed on Bi2.15WO6 enhance the photocatalytic reactivity of Bi2.15WO6 via the ligand-to-metal charge transfer pathway. We therefore suggest that dissolved oxygen is sequentially reduced to ≡Bi–OO• and then to ≡Bi–OOH on Bi2.15WO6, accompanied by H-abstraction from adsorbed or aqueous As(III) to ≡Bi–OO• and ≡Bi–OOH with the formation of H2O2 and the oxidation of As(III). This work enriches our understanding of the mechanisms involved in the photocatalytic oxidation of As(III).
研究领域:
环境科学
·
材料科学
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DOI
高影响因子
LANGMUIR
·
2024
·
IF 3.7
Hai-Tao Ren,Chao-Chen Cai,Peng-Yue Zhu,Cong Wang,Song-Hai Wu,Yong Liu,Xu Han
Photocatalytic technology is a popular research area for converting solar energy into environmentally friendly chemicals and is considered the greenest approach for producing H2O2. However, the corresponding reactive oxygen species (ROS) and pathway involved in the photocatalytic generation of H2O2 by the Bi2.15WO6-glucose system are still not clear. Quenching experiments have established that neither •OH nor h+ contribute to the formation of H2O2, and show that the formed surface superoxo (≡Bi–OO•) and peroxo (≡Bi–OOH) species are the predominant ROS in H2O2 generation. In addition, various characterizations indicate the enhanced electron-transfer on the surface of Bi2.15WO6 with increasing contents of glucose via the ligand-to-metal charge transfer pathway, confirming H-transfer from glucose to ≡Bi–OO• or ≡Bi–OOH. The increased production of H2O2 with decreasing bond dissociation energy (BDEO–H) values of various phenolic compounds again supports the H-transfer mechanism from phenolic compounds to ≡Bi–OO• and then to ≡Bi–OOH. DFT calculations further reveal that on the Bi2.15WO6 surface, oxygen is sequentially reduced to ≡Bi–OO• and ≡Bi–OOH, while H-transfer from H2O or glucose to ≡Bi–OO• and ≡Bi–OOH, resulting in the production of H2O2. The lower energy barrier of H-transfer from adsorbed glucose (0.636 eV) than that from H2O (1.157 eV) indicates that H-transfer is more favorable from adsorbed glucose. This work gives new insight into the photocatalytic generation of H2O2 by Bi2.15WO6 in the presence of glucose/phenolic compounds via the H-abstraction pathway.
研究领域:
材料科学
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环境科学
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催化化学
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DOI
PubMed
高影响因子
INDUSTRIAL & ENGINEERING CHEMISTRY RESEARCH
·
2022
·
IF 4.326
Wen-Shuang Zhu,Dai Sun,Ling-Li Yu,Shao-Qi Zhi,Yu-Dong Shan,Yi-Fang Lu,Hai-Tao Ren,Song-Hai Wu,Yong Liu,Xu Han
In this study, Bi2.15WO6 with different morphologies was successfully synthesized and used for the selective photooxidation of benzyl alcohol to benzaldehyde in aqueous solutions. High conversion (85%) and selectivity (85%) can be simultaneously achieved under alkaline conditions by adding ethylenediamine to protect the produced benzaldehyde from overoxidation. In the oxidation process, ≡Bi–OO• and ≡Bi–OOH on Bi2.15WO6, instead of OH• and O2•–, are the primary oxidizing species to sequentially abstract two H (H+ + e–) from benzyl alcohol, accompanied by the formation of H2O2. Meanwhile, h+ and OH– also minorly contribute to the selective oxidation of benzyl alcohol via the H-abstraction pathway. This study enriches our understanding of the oxidizing species involved in the selective photooxidation of benzyl alcohol to benzaldehyde.
研究领域:
材料科学
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催化化学
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环境科学
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产品关联
DOI
高影响因子
SEPARATION AND PURIFICATION TECHNOLOGY
·
2025
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IF 9
Yingying Fan,Junjie Liu,Xu Han
Photocatalytic generation of oxidative free radicals is an effective method to eliminate viruses and bacteria in air. Nevertheless, the underlying mechanisms governing the gas-phase sterilization remain unclear. In this study, the self-doped Bi 2.15 WO 6 was synthesized to prepare the Bi 2.15 WO 6 coating. In the presence of Bi 2.15 WO 6 coating, the average logarithmic degradation efficiencies ( LDEs ) are 3.82 and 3.07 for E. coli and S. aureus , respectively under UV illumination for 12.9 s, indicating its desirable sterilization efficiencies. In addition, the sterilization rates of E. coli and S. aureus slightly decrease by 3 % and 6 % after 30-repeated cycles, indicating the high stability of this catalytic coating. The 2,7-dichlorofluorescein (DCF) fluorescence experiments and SEM analysis indicate that reactive oxygen species (ROS) produced by Bi 2.15 WO 6 have effectively destroyed cell structure to achieve the complete inactivation. The N,N -diethyl-p-phenylenediamine sulfate (DPD) and radical trapping experiments further reveal that H 2 O 2 is the primary oxidizing species, and its yields are linearly proportional to the LDE values. The produced H 2 O 2 is further decomposed to •OH under UV irradiation to kill bacteria. Raman analysis confirms the presence of the intermediate species of surface ≡Bi-OO• superoxo and/or ≡Bi-OOH peroxo groups on Bi 2.15 WO 6 , which are the precursors of H 2 O 2 . In addition, the 3-D filter facilitates sterilization by the Bi 2.15 WO 6 in that it prolongs the duration of free radical via physically intercepting bioaerosols, thus apparently improving the degradation rate. This study provides new insights on the sterilization mechanism involved in the gas-phase photocatalytic processes.
研究领域:
环境科学
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生物学
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产品关联
DOI
高影响因子
CHEMICAL ENGINEERING JOURNAL
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2022
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IF 16.744
Tian-Yu Liu,Cong Wang,Yong-Zhe Han,Chang Bai,Hai-Tao Ren,Yong Liu,Xu Han
Bi 2+x WO 6 are a group of reactive photocatalysts in the photooxidation of various contaminants. However, their catalytic reactivity in the persulfate (PS)-based oxidation processes in the absence of light is still unknown. In this study, Bi 2.15 WO 6 shows a high reactivity in the catalytic oxidation of bisphenol A (BPA) by PS in the absence of light under alkaline conditions, and 20 mg L -1 BPA can be rapidly removed within 30 min at pH 10.0 with the low stoichiometry ratio of 1.79 between consumed PS and removed BPA. Characterizations of the oxidation products indicate that 98.4% of soluble BPA has been oxidatively polymerized to BPA polymers, instead of being oxidized to CO 2 and H 2 O. FTIR, Raman, XPS and electrochemical analyses confirm that surface Bi(III) is the reactive site for the adsorption of BPA and PS, which then initiates reactions between BPA and PS. DFT calculations reveal that the O-O bond in PS is moderately activated via the nonradical pathway after adsorbing on Bi(III), instead of being decomposed to SO 4 •− , followed by H-abstraction from BPA by the activated PS with the formation of phenoxyl radicals and the subsequent polymerization to BPA polymers. The apparently lower energy barrier from adsorbed BPA (Δ G = 0.056 eV) than that from dissolved BPA (Δ G = 0.263 eV) further reveals that H-abstraction from adsorbed BPA to the activated PS on the surface of Bi 2.15 WO 6 is more favorable than that from dissolved BPA. This study gives new insight on the efficient removal of recalcitrant contaminants via the H-abstraction pathway.
研究领域:
环境科学
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化学工程
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产品关联
DOI
高影响因子
PHYSICAL CHEMISTRY CHEMICAL PHYSICS
·
2020
·Vol. 22
·期 22
·12456-12464
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IF 3.43
Xiang-Ming Wang,Song-Hai Wu,Hai-Tao Ren,Peng-Yue Zhu,Cong Wang,Yong Liu,Shi-Wei Sun,Xiao-Cong Zhang,Yi-Ying Lin,Zi-He Meng,Shao-Yi Jia,Xu Han
Bi2+xWO6 is a cost-effective and environmentally friendly photocatalyst that shows high reactivity in the oxidation of various contaminants under visible light. However, under alkaline conditions, the reactive oxidative species in the Bi2+xWO6 system are still not clear yet. In this study, it is observed that the oxidation rates of As(III) increase with increasing pH values in the Bi2.15WO6 system. Photoluminescence and the Mott–Schottky analyses confirm that OH− promotes the separation and transfer of photogenerated electron–hole pairs over Bi2.15WO6, thus facilitating the oxidation of As(III). Electron spin resonance spectra analysis and quenching experiments rule out contributions of •OH, O2˙−, 1O2 and superoxo species to As(III) oxidation and indicate that surface –OOH and/or H2O2 are indeed the predominant species under alkaline conditions. The improved production of H2O2 by H-donors such as glucose and phenol, as well as the UV-vis diffuse reflectance and Raman analyses, further confirms the formation of surface –OOH on Bi2.15WO6 under alkaline conditions. In the dark, the significant higher oxidation rate of As(III) by H2O2–Bi2.15WO6 than that by H2O2 alone reveals that surface −OOH, instead of H2O2, plays an important role in As(III) oxidation. This study enriches our understanding of the diversity of reactive oxygen species (ROS) in the Bi2.15WO6 system and gives new insight into the mechanism involved in the oxidation of As(III) under alkaline conditions.
研究领域:
环境科学
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光催化
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材料科学
✓ 已验证
DOI
PubMed
高影响因子
RESEARCH ON CHEMICAL INTERMEDIATES
·
2023
·Vol. 49
·期 10
·4257-4274
·
IF 3.3
Cao Wenbo,Ren Haitao,Cai Chaochen,Li Dashuai,Li Tingting,Lou Chingwen,Lin Jiahorng
Photocatalysis is a promising technology for wastewater treatment. It is a key problem to develop photocatalytic materials that can efficiently remove tetracycline (TC) under weak light intensity. This article synthesized the UiO-66-NH 2 /Bi 2.15 WO 6 heterojunction using a solvothermal method, and its specific surface area increases by 2.1 times relative to Bi 2.15 WO 6 , endowing good adsorption capacity for TC. Compared with Bi 2.15 WO 6 , the heterojunction effectively improves the separation of electrons and holes and enhances the photocatalytic performance. Under weak light intensity (4 mW cm −2 ), the removal percentage of 50 mg L −1 TC can reach 78.0%, attributing to a synergistic effect between adsorption and photocatalysis. The free radical capture experiment showed that TC was photodegradation mainly under the action of hole (h + ) and superoxide radical (·O 2 − ). Finally, through LC/MS analysis, it is inferred that TC is degraded into H 2 O and CO 2 after a series of reactions such as deamination, dehydroxylation, amide bond breaking and ring opening. This study provides insights for the synthesis of more powerful photocatalysts for TC removal.
研究领域:
环境科学
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材料科学
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化学工程
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水处理
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产品关联
DOI
高影响因子
JOURNAL OF COLLOID AND INTERFACE SCIENCE
·
2022
·
IF 9.965
Hai-Tao Ren,Meng-Zhen Jing,Da-Shuai Li,Ting-Ting Li,Ching-Wen Lou,Jia-Horng Lin,Xu Han
Photocatalytic reduction of Cr(VI) in water environments attracts more attention; however, the mechanisms involved in this process have not been clearly elucidated yet. In this study, the photocatalytic reduction of Cr(VI) by polydopamine modified Bi 2.15 WO 6 (PDA/BWO) under visible light was conducted. Kinetics results show that PDA apparently accelerates the reduction of Cr(VI). The quasi-first-order kinetic constant of Cr(VI) reduction by 5PDA/BWO is 70.0 times that of the original BWO, reaching 0.070 min −1 . X-ray photoelectron spectroscopy, Fourier transform infrared spectroscopy , and Raman analyses confirm the formation of ligand-to-metal charge transfer (LMCT) complex [Bi(III) O C] between PDA and BWO. The formed Bi(III) O C complex enhances visible light response and narrows the bandgap of PDA/BWO. The photoelectrochemical and photoluminescent characterization further reveals that the formed Bi(III) O C complex inhibits the recombination of carriers, thus enhancing the photocatalytic reactivity of PDA/BWO. Electrons, are derived from three paths, including dye sensitization, LMCT and bandgap excitation, contribute to Cr(VI) reduction by PDA/BWO. This study provides new insights on the paths of Cr(VI) reduction by PDA/BWO under visible light.
研究领域:
环境科学
·
材料科学
✓ 已验证
产品关联
DOI
PubMed
高影响因子
危险品化学品经营许可证（带存储）