WO3 photocatalyst decorated with highly dispersed CoWO4 or CuWO4 nanoparticles(CoWO4/WO3 or CuWO4/WO3) was successfully synthesized using an in-situ impregnation method followed by solid-state reaction. The structure,...WO3 photocatalyst decorated with highly dispersed CoWO4 or CuWO4 nanoparticles(CoWO4/WO3 or CuWO4/WO3) was successfully synthesized using an in-situ impregnation method followed by solid-state reaction. The structure, morphology, photophysical property, and photocatalytic degradation mechanism of the CoWO4/WO3 or CuWO4/WO3 samples were investigated by XRD, SEM, TEM, EDS, HR-TEM, UV-vis DRS, SPV, and active trapping techniques. The XRD, SEM, and TEM results have revealed that CoWO4 or CuWO4 are highly dispersed on the WO3 surface, when the loading amount of CoWO4 or CuWO4 is small. However, obvious agglomeration is observed for the CoWO4 or CuWO4 particles, when the loading amount of CoWO4 or CuWO4 was increased. The visible-light photocatalytic degradation of RhB shows that all CoWO4/WO3 or CuWO4/WO3 samples exhibit superior photocatalytic performance as compared to pure WO3. This is mainly attributed to the formation of type II heterojunction between WO3 and CoWO4 or CuWO4, which can promote the photogenerated electrons and holes separation and transfer. Moreover, it is found that 0.2% CoWO4/WO3 or 0.2% CuWO4/WO3, in which MWO4 nanoparticles are uniformly dispersed on the surface of WO3, can achieve the most excellent photocatalytic activity among CoWO4/WO3 or CuWO4/WO3 samples, respectively. As compared with WO3, an enhancement about 9.1 times or 6.8 times in photocatalytic activity is observed on 0.2% CoWO4/WO3 or 0.2% CuWO4/WO3, respectively. Furthermore, the active species trapping experiment demonstrates that ·OH, h+, and ·O-2 generated during the photocatalytic process are all the reactive species in photocatalytic degradation of Rhodamine B(RhB) on CoWO4/WO3 or CuWO4/WO3. This study presents a strategy to design superior photocatalyst for organic compound degradation.展开更多
Iron(Fe)was successfully doped in CuWO4 photoanode films with a combined liquid-phase spin-coating method via the dopant sources of Fe(NO3)3,FeSO4 and FeCl3.The microstructure of the prepared films was characterized b...Iron(Fe)was successfully doped in CuWO4 photoanode films with a combined liquid-phase spin-coating method via the dopant sources of Fe(NO3)3,FeSO4 and FeCl3.The microstructure of the prepared films was characterized by x-ray diffraction,scanning electron microscopy,and atomic force microscopy.The light absorption and photoelectric conversion properties were evaluated by the UV-visible absorption spectra and monochromatic incident photon-to-electron conversion efficiency.The chemical composition and element combination of the samples were examined by x-ray photoelectron spectroscopy.A linear sweep voltammetric and stability test(I-t)were performed with an electrochemical workstation.The results show that the samples are uniform with a thickness of approximately 800 nm and that the photoelectrochemical performance of the doped films is heavily dependent on the Fe source and dopant concentration.Upon optimizing the doping conditions of Fe(NO3)3 and the optimal source,the photocurrent density in the Fe-doped CuWO4 photoanode film is improved by 78%from 0.267 mA/cm2 to 0.476 mA/cm2 at 1.23 V vs reversible hydrogen electrode.The underlying causes are discussed.展开更多
基金supported financially by the National Natural Science Foundation of China(21573101)the Program for Liaoning Excellent Talents in University(LR2017011)+1 种基金the support plan for Distinguished Professor of Liaoning Province([2015]153)the Liaoning BaiQianWan Talents program([2017]96)
文摘WO3 photocatalyst decorated with highly dispersed CoWO4 or CuWO4 nanoparticles(CoWO4/WO3 or CuWO4/WO3) was successfully synthesized using an in-situ impregnation method followed by solid-state reaction. The structure, morphology, photophysical property, and photocatalytic degradation mechanism of the CoWO4/WO3 or CuWO4/WO3 samples were investigated by XRD, SEM, TEM, EDS, HR-TEM, UV-vis DRS, SPV, and active trapping techniques. The XRD, SEM, and TEM results have revealed that CoWO4 or CuWO4 are highly dispersed on the WO3 surface, when the loading amount of CoWO4 or CuWO4 is small. However, obvious agglomeration is observed for the CoWO4 or CuWO4 particles, when the loading amount of CoWO4 or CuWO4 was increased. The visible-light photocatalytic degradation of RhB shows that all CoWO4/WO3 or CuWO4/WO3 samples exhibit superior photocatalytic performance as compared to pure WO3. This is mainly attributed to the formation of type II heterojunction between WO3 and CoWO4 or CuWO4, which can promote the photogenerated electrons and holes separation and transfer. Moreover, it is found that 0.2% CoWO4/WO3 or 0.2% CuWO4/WO3, in which MWO4 nanoparticles are uniformly dispersed on the surface of WO3, can achieve the most excellent photocatalytic activity among CoWO4/WO3 or CuWO4/WO3 samples, respectively. As compared with WO3, an enhancement about 9.1 times or 6.8 times in photocatalytic activity is observed on 0.2% CoWO4/WO3 or 0.2% CuWO4/WO3, respectively. Furthermore, the active species trapping experiment demonstrates that ·OH, h+, and ·O-2 generated during the photocatalytic process are all the reactive species in photocatalytic degradation of Rhodamine B(RhB) on CoWO4/WO3 or CuWO4/WO3. This study presents a strategy to design superior photocatalyst for organic compound degradation.
基金Project supported by the National Natural Science Foundation of China(Grant No.11204238)the Natural Science Foundation of Shaanxi Province,China(Grant No.2017JM1030).
文摘Iron(Fe)was successfully doped in CuWO4 photoanode films with a combined liquid-phase spin-coating method via the dopant sources of Fe(NO3)3,FeSO4 and FeCl3.The microstructure of the prepared films was characterized by x-ray diffraction,scanning electron microscopy,and atomic force microscopy.The light absorption and photoelectric conversion properties were evaluated by the UV-visible absorption spectra and monochromatic incident photon-to-electron conversion efficiency.The chemical composition and element combination of the samples were examined by x-ray photoelectron spectroscopy.A linear sweep voltammetric and stability test(I-t)were performed with an electrochemical workstation.The results show that the samples are uniform with a thickness of approximately 800 nm and that the photoelectrochemical performance of the doped films is heavily dependent on the Fe source and dopant concentration.Upon optimizing the doping conditions of Fe(NO3)3 and the optimal source,the photocurrent density in the Fe-doped CuWO4 photoanode film is improved by 78%from 0.267 mA/cm2 to 0.476 mA/cm2 at 1.23 V vs reversible hydrogen electrode.The underlying causes are discussed.
