Journal of Environmental Chemical Engineering
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2022
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IF 7.968
Lei Li,Jian Yang,Lei Yang,Fan Fu,Hao Xu,Ximei Fan
As one of the typical volatile organic compounds, toluene is harmful to human health and challenging to decompose effectively with traditional photocatalysts, such as TiO 2 or ZnO. Here, a trace Fe 3+ doped TiO 2 /Bi 2 WO 6 composite photocatalyst with abundant oxygen vacancies was successfully synthesized via a hydrothermal method and subsequently impregnation treatment. The Fe 3+ doped TiO 2 /Bi 2 WO 6 were optimized by adjusting the molar ration of TiO 2 and Bi 2 WO 6 , and the optimal molar ratio was found to be TiO 2 :Bi 2 WO 6 = 1:2. The obtained Fe (0.1) -TB 2 with only 0.1 wt% Fe 3+ dopant exhibited superior photocatalytic activity with over 90% toluene removal efficiency after 180 min under visible light irradiation. A series of characterizations reveal that the improved photocatalytic activity of Fe 3+ doped TiO 2 /Bi 2 WO 6 can be attributed to synergistic effects between the extension of photogenerated carrier lifetime and the increase of visible light absorption range by narrowing the energy bandgap (shortened about 0.32 eV) and the formation of oxygen vacancies. Furthermore, hydroxyl radicals and holes as the key reactive oxygen species (ROS) in the photodegradation reaction were confirmed by electron spin resonance (ESR) experiments. Therefore, introducing Fe-ions into TiO 2 /Bi 2 WO 6 photocatalysts is an effective way to enhance the photocatalytic activities, and the modified catalysts can be considered as a promising material for decomposing toluene and other VOCs.
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
APPLIED CATALYSIS B-ENVIRONMENTAL
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2020
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IF 16.683
Yunpeng Liu,Dongyan Shen,Qiao Zhang,Yuan Lin,Feng Peng
The artificial carbon dioxide (CO 2 ) photoreduction into useful chemicals utilizing solar energy demands the stable photocatalysts with high-efficiency charge separation and effective CO 2 adsorption capacity. For all this, for the first time, Bi 2 WO 6 photocatalysts with atomically thin structure along with hydrophobic and nonpolar surface are successfully designed and prepared using CTAB as assistant. The ultrathin feature with short diffusion distance significantly facilitates the charge separation. The hydrophobic surface, modified by nonpolar long carbon chains of CTA + , boosts both the mass-transfer and adsorption of CO 2 , meanwhile suppressing the H 2 O adsorption. Hence, the prepared photocatalyst exhibits a high-efficiency photocatalytic conversion of CO 2 in H 2 O vapor without co-catalyst due to high CO 2 concentration and sufficient photogenerated carriers. The photocatalytic mechanisms including adsorption concentration and activation process of CO 2 are further revealed by the in-situ diffuse reflectance infrared fourier transform spectra (DRIFTS). As a new feature, linearly adsorbed CO at 2035 cm −1 is found on hydrophobic surface of Bi 2 WO 6 , and the absorbance of CO is critical to the next reaction step for CH 4 generation. This innovation provides a facile avenue for the design of photocatalysts with remarkable CO 2 capture ability to achieve the practical application of photocatalytic CO 2 reduction.
研究领域:
材料科学
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环境科学
✓ 已验证
产品关联
DOI
高影响因子
APPLIED CATALYSIS B-ENVIRONMENTAL
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2024
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IF 20.2
Mingxia Lu,Lixia Yang,Ziyi Wu,Qi Wang,Menglei Wang,Jiajian Xu,Shuqu Zhang,Renjie Song,Weili Dai,Jianping Zou,Shenglian Luo
An air purifier that provides clean air will be popular if it is portable and capable of removing volatile organic chemicals and reducing exposure to bacteria. Herein, ultra-thin and dense Bi 2 WO 6 nanoflakes grown on W meshes specialize in offering abundant oxygen vacancies due to Na + driving laminar splitting. Under visible lights , the photogenerated carriers streaming along the ultrathin Bi 2 WO 6 surface produce bountiful reactive oxygen species for mineralizing VOCs and sweeping bacteria. Enriched with •O 2 - and •OH, a 15 cm*5 cm Na-Bi 2 WO 6 mesh can completely degrade 30 ppm toluene in 0.45 dm 3 reactor in 1 hour without producing any toxic intermediates like benzene, and its efficacy only decayed by 4% after a continuous 14-hour run. A cup-shaped air purifier was assembled with the Na-Bi 2 WO 6 mesh, enabling the rapid elimination of 1 ppm toluene, 2 ppm formaldehyde, and bacteria within a 120 dm 3 test space.
CAS / MDL:
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
CHEMICAL ENGINEERING JOURNAL
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2023
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IF 15.1
Mingwei Shen,Guoqing Zhang,Jiayou Liu,Yuhang Liu,Jiayuan Zhai,Haochuan Zhang,Hesheng Yu
Photocatalysis has been widely employed as a promising method for wastewater treatment. However, existing studies are primarily conducted in batch reactors. To the best of our knowledge, a continuous reactor has not been used to degrade xanthate residual in mineral beneficiation wastewater. In this work, a continuous fixed-bed photoreactor (CFPR) was first designed, and Bi 2 WO 6 photocatalysts coated on silica sands were used to degrade sodium isobutyl xanthate (SIBX) under visible light irradiation. The effects of various parameters, including catalyst loading, pH level, initial SIBX concentration, wastewater flow rate, calcium ion (Ca 2+ ) concentration, magnesium ion (Mg 2+ ) concentration, and zinc ions (Zn 2+ ), on the degradation efficiency, were systematically investigated. The results show that the photodegradation percentage of SIBX increases with increasing catalyst loading, decreasing initial concentration, and decreasing flow rate within the scope under investigation. Additionally, low concentrations (30 mg·L −1 ) of Ca 2+ and Mg 2+ ions favor the photodegradation of SIBX, whereas excessive Ca 2+ and Mg 2+ ions (240 mg·L −1 ) inhibit photocatalytic activity. The presence of Zn 2+ ions inhibits photodegradation percentage. Furthermore, the photodegradation percentage is slightly higher at alkaline than at acidic pH. The maximum degradation percentage reached 95.40 % after 70 min of visible light irradiation under optimal conditions. In addition, a fixed bed reactor model considering surface reaction kinetics and mass transfer constraints was established by combining the Langmuir-Hinshelwood (L-H) kinetic equations and the series resistance theory. This model can accurately estimate the intrinsic kinetic parameters and can well predict degradation efficiency with a root-mean-square-error (RMSE) of 4.24 %. Finally, the bottleneck for improving the performance of the reactor can be identified under different conditions.
研究领域:
环境科学
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化学工程
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材料科学
✓ 已验证
产品关联
DOI
高影响因子
危险品化学品经营许可证（带存储）