APPLIED CATALYSIS B-ENVIRONMENTAL
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2019
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IF 14.229
Yingguang Zhang,Muyan Wu,Y.H. Kwok,Yifei Wang,Wei Zhao,Xiaolong Zhao,Haibao Huang,Dennis Y.C. Leung
A series of TiO 2 /MnO 2 heterojunction catalysts were fabricated through an in-situ hydrothermal method, and for the first time, catalysts with this heterojunction structure were used for VUV-PCO toluene degradation. After the MnO 2 coating, the TiO 2 /MnO 2 catalysts performed excellently for both VOCs degradation and residual ozone decomposition with removal efficiency reaching 96.0% and 99.9%, respectively. The enhanced photocatalytic activity towards toluene degradation could be attributed to the heterojunction structure of TiO 2 /MnO 2 , which provides excellent contact between MnO 2 and TiO 2 , and suppresses the recombination of photogenerated electron-hole pairs. Moreover, benefiting from the MnO 2 , the ozone generated in the system could be efficiently utilized and eliminated during the VUV-PCO process. The photocatalytic mechanism of TiO 2 /MnO 2 for the toluene degradation and ozone decomposition was proposed.
研究领域:
环境科学
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材料科学
✓ 已验证
DOI
高影响因子
Journal of Energy Storage
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2024
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IF 8.9
Qian Xie,Zhengxin Cai,Zhi Zhang,Yongjun Li,Xinyu Zhang,Jianmin Wang,Jiajia Cai
Deliberate engineering of the excellent skeleton to support the MnO 2 can facilitate electron transfer and charge distribution, contributing to high-energy/power supercapacitance. Herein, an ambient and cost-effective hydrogen-doped method is innovatively employed to prepare H-TiO 2 nanotube arrays (H-TNTAs), where the MnO 2 grows further in situ. After hydrogenation, the capacitance increases by 40-fold, attributing to the improved conductivity. The H-TNTAs supported MnO 2 provides good pseudocapacitive performance, with a specific capacitance of 430.1 F/g at a discharging current of 300 μAcm −2 . The H-TNTAs@MnO 2 coupled active carbon (AC) in 0.5 M Na 2 SO 4 electrolyte is fabricated as the aqueous asymmetric supercapacitor (ASC). The ASC device displays a high energy density of 43.9 Wh kg −1 at a power density of 550 W kg −1 , with an output voltage of 2.2 V and a superior capacitance stability of 86.7 % (over 5000 cycles). The idea for designing the hydrogenated transition metal oxides can be extended to other high-performance metal oxide electrodes for energy storage devices.
研究领域:
材料科学
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能源存储
✓ 已验证
DOI
高影响因子
CARBOHYDRATE POLYMERS
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2022
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IF 10.723
Yingkun Song,Min Jiang,Lijuan Zhou,Hongsheng Yang,Jianming Zhang
The cellulose nanocrystal (CNC)/transition metal oxide hybrid porous microspheres usually have high adsorption performance and degradability, and show promising applications in the field of wastewater treatment. However, single metal oxides are limited by the forbidden band width and electron-hole complexation, and often fail to achieve good effluent treatment. Herein, a CNC/manganese dioxide/titanium dioxide porous microspheres are prepared by the combination of bubble template and ionic crosslinking between sodium alginate and Ca 2+ ions as a matrix. Based on the synergistic effect of two kinds of transition metal oxide , the degradation efficiency of CNC/MnO 2 /TiO 2 porous microspheres for methylene blue is as high as 97.0%, showing easy recovery process and rapid regeneration of this material. Besides, its maximum removal of dyes reaches up to 310.2 mg/g, which is much higher than most CNC based adsorption materials. The concept of concerted catalysis can to explain the origin for excellent performance of as-prepared hybrid microspheres.
研究领域:
材料科学
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环境科学
✓ 已验证
产品关联
DOI
PubMed
高影响因子
Nano Research
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2023
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IF 9.9
Yu Fan,Luo Chunjia,Niu Xiaohan,Chao Min,Zhang Pengfei,Yan Luke
Graphitic carbon nitride (g-C 3 N 4 ) nanosheets have attracted widespread interest in the construction of advanced separation membranes. However, dense stacking and a single functionality have limited the membrane development. Here, an advanced two-/three-dimensional (2D/3D) g-C 3 N 4 /TiO 2 @MnO 2 membrane is constructed by intercalating 3D TiO 2 @MnO 2 nanostructures into g-C 3 N 4 nanosheets. The 3D flower-like nanostructures broaden the transport channels of the composite membrane. The membrane can effectively separate five oil-in-water (O/W) emulsions, with a maximum flux of 3265.67 ± 15.01 L·m −2 ·h −1 ·bar −1 and a maximum efficiency of 99.69% ± 0.45% for toluene-in-water emulsion (T/W). Meanwhile, the TiO 2 @MnO 2 acts as an excellent electron acceptor and provides positive spatial separation of electrons–holes (e − –h + ). The formation of 2D/3D heterojunctions allows the material with wider light absorption and smaller bandgap (2.10 eV). These photoelectric properties give the membrane good degradation of three different pollutants, with about 100% degradation for methylene blue (MB) and malachite green (MG). The photocatalytic antibacterial efficiency of the membrane is also about 100%. After cyclic experiment, the membrane maintains its original separation and photocatalytic capabilities. The remarkable multifunctional and self-cleaning properties of the g-C 3 N 4 based membrane represent its potential value for complex wastewater treatment.
研究领域:
材料科学
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环境科学
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化学工程
✓ 已验证
产品关联
DOI
高影响因子
Journal of Environmental Chemical Engineering
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2023
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IF 7.7
Xixi Chen,Wanyi Fu,Yulong Yang,Yanjun Li,Kai Yang,Xuanbo Xu,Xihui Zhang
Atomic H* has been reported to be thermodynamically feasible for activating hydrogen peroxide (H 2 O 2 ) to produce radicals, while the nonradical pathway and the contributions of metal sites and atomic H* in H 2 O 2 activation need further exploration. In this study, a TiO 2 @MnO 2 catalyst was synthesized via a facile hydrothermal method and surprisingly found to produce atomic H* over Mn sites in water without external energy input (e.g., light and electricity). Atomic H* plays an essential role in the activation of H 2 O 2 via a nonradical pathway, which induces the removal of tiamulin up to 80.4–91.7% in 20 min at a wide pH range of 4.0–11.0. Density function theory calculations prove that atomic H* owns a much lower total energy barrier (ΔG total = 0.68 eV) for the decomposition of H 2 O 2 to generate superoxide and singlet oxygen than Mn sites (ΔG total = 2.90 eV). This study is a re-visit to the mechanism of activating H 2 O 2 via atomic H* for efficient degradation of emerging organic contaminants .
研究领域:
环境科学
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催化
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水处理
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化学工程
✓ 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）