KEY ENGINEERING MATERIALS
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2012
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IF 0
Hai Feng Chen,Ting Yan
Using Bi(NO3)3•5H2O, Na2WO4•2H2O and Ti• (OC4H9)4 as the main raw materials, different alcohol solvent as medium, hexamethylene tetramine as sink set agent, tungsten bismuth and titanium dioxide composite powder were prepared by hydrothermal synthesis. It was characterized by XRD and DRS. The methyl orange imitated sewage, we study the impacts of calcinations’ temperature, catalyst amount, concentration, illumination time and pH on photocatalytic performance of Bi2WO6/TiO2 samples under visible light. The results showed that calcinations’ temperature 400 oC was the best, because the forbidden band gap decreased with temperature increased, but phase transition or decomposition exothermic of the samples would occurre at higher than 400 degree. The Bi2WO6/TiO2 prepared under acidic condition had only 2.41 eV as the smallest forbidden band gap of the samples.
研究领域:
材料科学
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环境科学
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DOI
SEPARATION AND PURIFICATION TECHNOLOGY
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2024
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IF 8.1
Tingzhe Shen,Danni Zeng,Ze Liu,Yadong Hu,Yaxi Tian,Jun Song,Tao Yang,Rongfeng Guan,Changjian Zhou
Improving the efficiency of photogenerated carrier separation by designing heterojunction photocatalysts remains an important challenge. In this study, TiO 2 nanofibers were prepared by electrospinning, Bi/Bi 2 WO 6 /TiO 2 heterojunctions were constructed by hydrothermal method, and verified by characterization techniques. The heterojunction had good photodegradation activity to sulfamethoxazole (SMX) under ultraviolet and visible light irradiation (96.4 % within 60 min). The enhanced photodegradation activity of Bi/Bi 2 WO 6 /TiO 2 nanocomposites can be attributed to the synergistic effect of S-Scheme mechanism and Bi metal plasma action. In addition, Bi metals can generate a large number of electron-hole pairs under the action of surface plasmon resonance (SPR). In addition, the influence factors such as pH, SMX concentration and catalyst loading were studied. According to the detected intermediates, the photocatalytic degradation pathway of SMX was studied. The results of free radical capture experiment and ESR show that ·O 2 – and h + free radicals play an important role in the decomposition of SMX. The cyclic experiments show that Bi/Bi 2 WO 6 /TiO 2 nanocomposites have excellent stability and reuse characteristics. Finally, the mechanism of photocatalytic degradation of SMX was described. This study provides a promising perspective for the preparation and development of S-Scheme heterojunction photocatalysts based on Bi 2 WO 6 .
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
CERAMICS INTERNATIONAL
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2023
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IF 5.2
Yujia Wang,Zhigang Zhang,Yijiang Chen,Zhengfa Zhu,Hao Wang,Xiaoning Tang
Designing efficient antimicrobials for the rapid disinfection of water is increasingly critical owing to the rising threat of pathogenic microorganisms. In this study, direct Z-scheme Bi 2 WO 6 /TiO 2 heterojunctions were constructed using a simple in situ hydrothermal method. The optimal Bi 2 WO 6 /TiO 2 Z-scheme heterojunction inhibited 98.80 % of Escherichia coli (5 × 10 8 CFU mL −1 ) at 0.35 mg mL −1 and 99.33 % of Staphylococcus aureus (5 × 10 8 CFU mL −1 ) at 0.5 mg mL −1 after 10 min of light-emitting diode (LED) light irradiation. Furthermore, in antibiotic degradation experiments, Bi 2 WO 6 /TiO 2 had a 92.91 % removal rate for ciprofloxacin with a pseudo-second-order degradation rate constant ( k ) of 0.056 min −1 after 240 min of irradiation. The antibacterial mechanism of Bi 2 WO 6 /TiO 2 was systematically investigated and confirmed to occur by LED light-driven surface activation and efficient charge transfer. The surface and interfacial structures of the Bi 2 WO 6 /TiO 2 samples were studied by high-resolution transmission electron microscopy, Raman spectroscopy, and X-ray photoelectron spectroscopy. The antibacterial mechanism was studied by controlled experiments and electron spin resonance analyses, which revealed that the primary antibacterial mechanism of Bi 2 WO 6 /TiO 2 is oxidative sterilisation via generated reactive oxygen species. Time-resolved fluorescence spectroscopy was used to analyse the charge-transfer pathway in Bi 2 WO 6 /TiO 2 , which demonstrated that the spatial separation of the redox-active sites extended the lifetimes of the photogenerated carriers, enhancing the oxidative destruction of bacteria. This comprehensive understanding paves the way for the design of new Z-type heterojunction photocatalytic materials for antimicrobial applications.
研究领域:
材料科学
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环境科学
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化学
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微生物学
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光催化
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产品关联
DOI
高影响因子
ADVANCED POWDER TECHNOLOGY
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2019
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IF 3.25
Linwei Ji,Baojiang Liu,Yajie Qian,Qing Yang,Pin Gao
Composites coupling different semiconductors have attracted increasing attention for photocatalytic application owing to low visible-light absorption capability and weak photocatalytic activity of the single-component system. In this study, Bi 2 WO 6 /TiO 2 /rGO ternary composites, successfully synthesized by a facile hydrothermal method, were manifested as an outstanding visible-light-response photocatalyst for the disinfection towards E. coli . X-ray diffraction, Fourier-transform infrared, and X-ray photoelectron spectroscopy demonstrated that GO coupled in the composites was efficiently reduced to rGO during the hydrothermal process, which was greatly beneficial for enhancing light harvest, promoting charge separation, and improving photocatalytic disinfection activity. UV–vis diffuse reflectance spectra, photoluminescence and time-resolved photoluminescence, photocurrent measurements, and ultraviolet photoelectron spectroscopy clearly showed that Bi 2 WO 6 /TiO 2 /rGO composites had narrower band gap energy and much better suppression capability of photoinduced electron-hole recombination in comparison to the pure Bi 2 WO 6 and TiO 2 , and Bi 2 WO 6 /TiO 2 . The radical trapping results revealed that the photogenerated holes (h + ) were the leading active species responsible for the effective inactivation of E. coli under visible-light irradiation. Hence, the underlying mechanism for the enhanced photocatalytic disinfection performance of Bi 2 WO 6 /TiO 2 /rGO composites was proposed. This study provides new insight into the design and development of composite materials with enhanced photocatalytic activity, which can be an inspiring alternative for environmental application.
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
危险品化学品经营许可证（带存储）