A new electrochemically-modified BiVO_(4)-MoS_(2)-Co_(3)O_(4)(represented as E-BiVO_(4)-MoS_(2)-Co_(3)O_(4))thin film electrode was successfully synthesized for environmental application.MoS_(2)and Co_(3)O_(4)were gro...A new electrochemically-modified BiVO_(4)-MoS_(2)-Co_(3)O_(4)(represented as E-BiVO_(4)-MoS_(2)-Co_(3)O_(4))thin film electrode was successfully synthesized for environmental application.MoS_(2)and Co_(3)O_(4)were grown on the surface of Bi VO 4 to obtain BiVO_(4)-MoS_(2)-Co_(3)O_(4).E-BiVO_(4)-MoS_(2)-Co_(3)O_(4)film was achieved by further electrochemical treatment of BiVO_(4)-MoS_(2)-Co_(3)O_(4).The asprepared E-BiVO_(4)-MoS_(2)-Co_(3)O_(4)exhibited significantly enhanced photoelectrocatalytic activity.The photocurrent density of E-BiVO_(4)-MoS_(2)-Co_(3)O_(4)thin film is 6.6 times that of Bi VO 4 under visible light irradiation.The degradation efficiency of E-BiVO_(4)-MoS_(2)-Co_(3)O_(4)for bisphenol A pollutant was 81.56%in photoelectrochemical process.The pseudo-first order reaction rate constant of E-BiVO_(4)-MoS_(2)-Co_(3)O_(4)film is 3.22 times higher than that of Bi VO 4.And its reaction rate constant in photoelectrocatalytic process is 14.5 times or 2 times that in photocatalytic or electrocatalytic process,respectively.The improved performance of E-BiVO_(4)-MoS_(2)-Co_(3)O_(4)was attributed to the synergetic effects of the reduction of interfacial charge transfer resistance,the formation of oxygen vacancies and sub-stoichiometric metal oxides and higher separation efficiency of photogenerated electron-hole pairs.E-BiVO_(4)-MoS_(2)-Co_(3)O_(4)is a promising composite material for pollutants removal.展开更多
A series of CeO2-Co3O4 mixed oxide catalysts with different Co/（Co＋Ce） atomic ratios were synthesized by citric acid sol-gel method and used for catalytic oxidation of formaldehyde（HCHO）. Many techniques such as ...A series of CeO2-Co3O4 mixed oxide catalysts with different Co/（Co＋Ce） atomic ratios were synthesized by citric acid sol-gel method and used for catalytic oxidation of formaldehyde（HCHO）. Many techniques such as Brumauer-Emmett-Teller（BET）, X-ray diffraction（XRD）, scanning electron microscopy（FE-SEM）, temperature programmed reduction（H_2-TPR）, temperature-programmed desorption（O_2-TPD） and X-ray photoelectron spectroscopy（XPS） were used to characterize catalysts. The results of catalytic performance tests showed that the catalyst CeO_2-Co_3O_4 with Co/（Co＋Ce） ratio of 0.95 exhibited the best performance, and the temperature of complete oxidation of HCHO was 80 oC. The analytical results indicated that the addition of CeO_2 enhanced the specific surface area of Co_3O_4 and the fine dispersion of both of them. Moreover, the strong interaction between CeO_2 and Co_3O_4 resulted in the unique redox properties, which enhanced the available surface active oxygen and led to high valence state of cobalt oxide species. All those effects played crucial roles in the excellent performance of CeO_2-Co_3O_4 for the HCHO oxidation.展开更多
基金financially supported by the Zhejiang Provincial Natural Science Foundation of China(Nos.LY18B060003,LR18B070001,and LY16B060001)the National Natural Science Foundation of China(Nos.21576237,21876154 and 21477114)Graduate Innovation Foundation of Zhejiang Gongshang University(No.1260KZN0217059G)。
文摘A new electrochemically-modified BiVO_(4)-MoS_(2)-Co_(3)O_(4)(represented as E-BiVO_(4)-MoS_(2)-Co_(3)O_(4))thin film electrode was successfully synthesized for environmental application.MoS_(2)and Co_(3)O_(4)were grown on the surface of Bi VO 4 to obtain BiVO_(4)-MoS_(2)-Co_(3)O_(4).E-BiVO_(4)-MoS_(2)-Co_(3)O_(4)film was achieved by further electrochemical treatment of BiVO_(4)-MoS_(2)-Co_(3)O_(4).The asprepared E-BiVO_(4)-MoS_(2)-Co_(3)O_(4)exhibited significantly enhanced photoelectrocatalytic activity.The photocurrent density of E-BiVO_(4)-MoS_(2)-Co_(3)O_(4)thin film is 6.6 times that of Bi VO 4 under visible light irradiation.The degradation efficiency of E-BiVO_(4)-MoS_(2)-Co_(3)O_(4)for bisphenol A pollutant was 81.56%in photoelectrochemical process.The pseudo-first order reaction rate constant of E-BiVO_(4)-MoS_(2)-Co_(3)O_(4)film is 3.22 times higher than that of Bi VO 4.And its reaction rate constant in photoelectrocatalytic process is 14.5 times or 2 times that in photocatalytic or electrocatalytic process,respectively.The improved performance of E-BiVO_(4)-MoS_(2)-Co_(3)O_(4)was attributed to the synergetic effects of the reduction of interfacial charge transfer resistance,the formation of oxygen vacancies and sub-stoichiometric metal oxides and higher separation efficiency of photogenerated electron-hole pairs.E-BiVO_(4)-MoS_(2)-Co_(3)O_(4)is a promising composite material for pollutants removal.
基金supported by the Doctoral Program of Xi'an Shiyou University(134010155)Shaanxi Provincial College Students'Inno vative Entrepreneurial Training Program(No.2016107051360 and 201610705046)
文摘A series of CeO2-Co3O4 mixed oxide catalysts with different Co/（Co＋Ce） atomic ratios were synthesized by citric acid sol-gel method and used for catalytic oxidation of formaldehyde（HCHO）. Many techniques such as Brumauer-Emmett-Teller（BET）, X-ray diffraction（XRD）, scanning electron microscopy（FE-SEM）, temperature programmed reduction（H_2-TPR）, temperature-programmed desorption（O_2-TPD） and X-ray photoelectron spectroscopy（XPS） were used to characterize catalysts. The results of catalytic performance tests showed that the catalyst CeO_2-Co_3O_4 with Co/（Co＋Ce） ratio of 0.95 exhibited the best performance, and the temperature of complete oxidation of HCHO was 80 oC. The analytical results indicated that the addition of CeO_2 enhanced the specific surface area of Co_3O_4 and the fine dispersion of both of them. Moreover, the strong interaction between CeO_2 and Co_3O_4 resulted in the unique redox properties, which enhanced the available surface active oxygen and led to high valence state of cobalt oxide species. All those effects played crucial roles in the excellent performance of CeO_2-Co_3O_4 for the HCHO oxidation.
