Preparation of Ce doped CNTs-TiO2 photocatalyst and its NO oxidation performance
ZHANG Jianwei1,, YUAN Peng1, WANG Jianqiao1, SHEN Boxiong1,2,,, ZHANG Yanfang3 1.School of Energy and Environment Engineering, Hebei University of Technology, Tianjin 300401, China 2.Tianjin Key Laboratory of Clean Energy and Pollution Control, Tianjin 300401, China 3.Tangshan Hengtong Technology Co. Ltd., Tangshan 063300, China
Abstract:In order to investigate the application potential of photocatalysis on flue gas denitration after wet desulfurization, metal and non-metal doped CNTs-TiO2 composite photocatalyst was prepared by sol-gel method, and the NO oxidation performance of the catalyst was tested and compared under simulated flue gas conditions. SEM, BET, XRD, Raman, XPS, DRS and other means were used to characterize the photocatalyst. The results showed that the oxidation efficiency of TiO2 was the lowest, the oxidation efficiency of photocatalyst doped with metal was slightly higher than that of photocatalyst doped with non-metal, and the oxidation efficiency of photocatalyst compounded with CNTs was significantly improved. Among above catalytic materials, CNTs-Ce/TiO2 had the larger specific surface area and the shortest Ti—O bond length, which facilitated the transfer of photo-generated electrons to CNTs along Ti—O bonds, formed more trivalent cerium oxides, and was conducive to the oxygen adsorption on the catalyst surface. Lower band gap width and great ultraviolet light absorbance showed the most excellent removal efficiency in NO oxidation performance test, and the efficiency increased by 19% compared with TiO2 and by 13% compared with CNTs-TiO2. According to the analysis, Ce and CNTs showed a synergistic effect. Ce doped TiO2 could effectively inhibit the combination of photogenic carriers, thus improving photocatalytic activity. Composite CNTs elevated the specific surface area of the catalyst and the formation of oxygen vacancies, thus promoting the whole catalytic oxidation reaction. Key words:carbon nanotubes/ TiO2/ flue gas denitration/ photocatalytic.
图1实验系统示意图 Figure1.Schematic diagram of the experimental system
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1.School of Energy and Environment Engineering, Hebei University of Technology, Tianjin 300401, China 2.Tianjin Key Laboratory of Clean Energy and Pollution Control, Tianjin 300401, China 3.Tangshan Hengtong Technology Co. Ltd., Tangshan 063300, China Received Date: 2019-09-05 Accepted Date: 2019-10-10 Available Online: 2020-07-10 Keywords:carbon nanotubes/ TiO2/ flue gas denitration/ photocatalytic Abstract:In order to investigate the application potential of photocatalysis on flue gas denitration after wet desulfurization, metal and non-metal doped CNTs-TiO2 composite photocatalyst was prepared by sol-gel method, and the NO oxidation performance of the catalyst was tested and compared under simulated flue gas conditions. SEM, BET, XRD, Raman, XPS, DRS and other means were used to characterize the photocatalyst. The results showed that the oxidation efficiency of TiO2 was the lowest, the oxidation efficiency of photocatalyst doped with metal was slightly higher than that of photocatalyst doped with non-metal, and the oxidation efficiency of photocatalyst compounded with CNTs was significantly improved. Among above catalytic materials, CNTs-Ce/TiO2 had the larger specific surface area and the shortest Ti—O bond length, which facilitated the transfer of photo-generated electrons to CNTs along Ti—O bonds, formed more trivalent cerium oxides, and was conducive to the oxygen adsorption on the catalyst surface. Lower band gap width and great ultraviolet light absorbance showed the most excellent removal efficiency in NO oxidation performance test, and the efficiency increased by 19% compared with TiO2 and by 13% compared with CNTs-TiO2. According to the analysis, Ce and CNTs showed a synergistic effect. Ce doped TiO2 could effectively inhibit the combination of photogenic carriers, thus improving photocatalytic activity. Composite CNTs elevated the specific surface area of the catalyst and the formation of oxygen vacancies, thus promoting the whole catalytic oxidation reaction.
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