APPLIED SURFACE SCIENCE
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2022
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IF 7.392
Bingcai Chen,Pengpeng Li,Bing Wang,Yingde Wang
CO sensor is helpful to monitor the working state of combustion equipment, such as industrial boilers and engines, and to ensure the production process and human life safety. However, balancing fast response/recovery and high response value for metal oxide CO sensors remains a challenge. In this work, based on band gap engineering, porous TiO 2 /CeO 2 NSs with different TiO 2 coupling amounts were prepared by hydrothermal method combined with flame annealing. The heterojunction composed of TiO 2 and CeO 2 narrowed the energy band width of the composite system and made the electron transmission more efficient, which endowed TiO 2 /CeO 2 NSs with good gas sensing properties. The results indicated that the response value of TiO 2 /CeO 2 NSs is 9.78 time that of CeO 2 NSs. Its ultrafast response/recovery time (2 s/6 s), good CO selectivity and wide CO monitoring range (500 ppb-5000 ppm) are also impressive. The TiO 2 /CeO 2 NSs sensor has great potential for rapid CO monitoring.
研究领域:
材料科学
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传感器技术
✓ 已验证
产品关联
DOI
高影响因子
CHINESE CHEMICAL LETTERS
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2021
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IF 6.779
Decai Yang,Yachao Xu,Kai Pan,Chuanxin Yu,Jiaxing Wu,Mingxia Li,Fan Yang,Yang Qu,Wei Zhou
Surface oxygen vacancy defects of mesoporous CeO 2 nanosheets assembled microspheres (D-CeO 2 ) are engineered by polymer precipitation, hydrothermal and surface hydrogenation strategies. The resultant D-CeO 2 with a main pore diameter of 9.3 nm has a large specific surface area (~102.3 m 2 /g) and high thermal stability. The mesoporous nanosheets assembled microsphere structure prevents the nanosheets from aggregation, which is beneficial to effective mass transfer and shortens the migration distance of charge carriers. After surface hydrogenation, the photoresponse extends to long wavelength region, combing with the band gap from 2.63 eV reduced to 2.39 eV. Under AM 1.5 G radiation, the photocatalytic degradation rate of tetracycline (TC) can be up to 99.99%, which is three times as high as that of pristine CeO 2 microspheres . The excellent solar-driven photocatalytic performance can be attributed to the efficient surface oxygen vacancy engineering and the mesoporous nanosheets assembled microsphere structure, which narrows the band gap, shortens the migration distance of carriers, promotes the spatial separation of photogenerated electron-hole pairs and favors mass transfer. The strategy provides new insights for fabricating other high-efficient oxide photocatalysts .
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
ChemNanoMat
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2019
·Vol. 5
·期 6
·831-837
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IF 3.431
Xiaoqing Wang,Jijian Xu,Zongxiao Wu,Mingjia Zhi,Zhanglian Hong,Fuqiang Huang
Graphical Triple threat : The ternary catalyst Co-NC-CeO 2 was synthesized via a simple ‘one-pot’ and ‘one-step’ method. This catalyst exhibited excellent ORR performance, with a half-wave potential of 817 mV (vs. RHE), a diffusion limited current density of 4.72 mA cm −2 , and a good durability (half-wave potential exhibiting a negative shift of only 17 mV after 1000 cycles), due to the synergistic effects between Co nanoparticles, the nitrogen-doped carbon (NC) layer and CeO 2 nanosheets. The oxygen reduction reaction (ORR) is the key cathode reaction in renewable-energy technologies. Developing highly efficient, low-cost, methanol-tolerant and durable ORR catalysts is highly needed. In this research, we reported a simple complexing-coprecipitation method to synthesize CeO 2 nanosheets encapsulated by a nitrogen-doped carbon (NC) layer with uniformly dispersed Co nanoparticles catalysts on the surface. In particular, the 0.5Co-NC-CeO 2 sample exhibits high ORR catalytic activity with an onset potential of 875 mV (vs. RHE), a diffusion-limited current density of 4.72 mA/cm 2 and a positive half-wave potential of 817 mV (vs RHE), while 20% Pt/C presents an onset potential of 934 mV (vs. RHE), a diffusion limited current density of 5.8 mA/cm 2 and half-wave potential of 850 mV (vs. RHE). In addition, the catalyst 0.5Co-NC-CeO 2 also possesses a robust durability, that is the half-wave potential exhibits a negative shift of only 17 mV after 1000 cycles. The enhanced ORR performance can be attributed to the synergistic effect among Co, the nitrogen-doped carbon layer and CeO 2 . The results demonstrated here have implications in designing non-Pt ORR catalysts.
研究领域:
材料科学
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催化化学
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能源技术
✓ 已验证
产品关联
DOI
高影响因子
JOURNAL OF CATALYSIS
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2023
·
IF 7.3
Yuanfeng Li,Tian Qin,Yaxiao Ma,Jing Xiong,Peng Zhang,Kezhen Lai,Xi Liu,Zhen Zhao,Jian Liu,Liwei Chen,Yuechang Wei
Herein, a series of Co x -CeO 2 nanosheet catalysts were elaborately synthesized by a one-step hydrothermal method. The CeO 2 microsphere with crossed nanosheets can improve the soot-catalyst contact efficiency and the lattice substitution of Co ions for cerium sites in CeO 2 results in the oriented lattice bending of Co-CeO 2 nanosheets for improving adsorption/activation properties of NO and O 2 . Co 2 -CeO 2 catalyst displays the highest H 2 O-tolerance activity ( T 50 = 334 °C, TOF = 1.32 h −1 ) and excellent stability during soot oxidation in the presence of H 2 O. Combined with characterizations and DFT calculations, the mechanism was proposed: the active edge sites located at the oriented lattice bending of Co-CeO 2 nanosheets can activate surface oxygen and gaseous O 2 , and active oxygen species can boost NO oxidation to NO 2 , which is a crucial step of NO x -assistant catalytic mechanism for soot oxidation. It provides a promising way for the rational design of high-performance non-noble metal catalysts for soot oxidation in practical applications.
研究领域:
催化
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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
RARE METALS
·
2025
·
IF 11
Wang Ding,Qin Rui-Jie,Yu Jie-Jie,Hu Jin-Wu,Zhang Wen-Hui,Xu Hui,Xu Jing-Cheng,Liao Qiao-Bo,Li Hui-Jun,Wang Xu-Hui
The semiconductor gas sensors used for xylene gas detection in real time has been restricted by the inadequate sensitivity and selectivity. Constructing a bilayer cascade sensor with the catalysis-gas sensitivity synergistic is considered as an effective solution. Herein, the Ag@CeO 2 nanosheets are synthesized by heat treating the Ag@Ce-MOF, which synthesized via solvothermal method. The morphological evolution of cerium metal–organic framework (Ce-MOF), regulated by Ag ions, is investigated, and the transformation mechanism is proposed. The bilayer sensors were constructed by using WO 3 nanofibers, prepared via the electrospinning method, as the sensitive layer and the Ag@CeO 2 nanosheets as the catalytic layer, respectively. The bilayer sensors exhibit remarkable performance in response to xylene. The response value ( R a / R g ) of WO 3 /Ag@CeO 2 sensor to 10 ppm xylene gas reaches 32.13 at the operating temperature of 160 °C. Additionally, the sensor displays an exceptional response to even trace amounts of xylene, as low as parts per billion (ppb). The catalysis-gas sensitivity synergistic mechanism was elucidated by capturing catalytic intermediates using online mass spectrometry. These findings provide a novel strategy for benzene series (BTEX) sensor and offer a novel approach to prepare two-dimensional Ce-MOF and its derived materials with tailored properties. Graphical abstract
研究领域:
材料科学
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环境科学
·
化学
✓ 已验证
产品关联
DOI
高影响因子
ENVIRONMENTAL SCIENCE & TECHNOLOGY
·
2018
·
IF 6.653
Qiguang Dai,Zhiyong Zhang,Jiaorong Yan,Jinyan Wu,Grayson Johnson,Wei Sun,Xingyi Wang,Sen Zhang,Wangcheng Zhan
Tuning the nature and profile of acidic and basic sites on the surface of redox-active metal oxide nanostructures is a promising approach to constructing efficient catalysts for the oxidative removal of chlorinated volatile organic compounds (CVOCs). Herein, using dichloromethane (DCM) oxidation as a model reaction, we report that phosphate (POx) Brønsted acid sites can be incorporated onto a CeO2 nanosheet (NS) surface via an organophosphate-mediated route, which can effectively enhance the CeO2’s catalytic performance by promoting the removal of chlorine poisoning species. From the systematic study of the correlation between POx composition, surface structure (acid and basic sites), and catalytic properties, we find that the incorporated Brønsted acid sites can also function to decrease the amount of medium-strong basic sites (O2–), reducing the formation of chlorinated organic byproduct monochloromethane (MCM) and leading to the desirable product, HCl. At the optimized P/Ce ratio (0.2), the POx–CeO2 NSs can perform a stable DCM conversion of 65–70% for over 10 h at 250 °C and over 95% conversion at 300 °C, superior to both pristine and other phosphate-modified CeO2 NSs. Our work clearly identifies the critical role of acid and basic sites over functionalized CeO2 for efficient catalytic CVOCs oxidation, guiding future advanced catalyst design for environmental remediation.
研究领域:
环境科学
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催化化学
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材料科学
✓ 已验证
DOI
高影响因子
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