A graphite carbon nitride(g-C3N4)modified Bi4O5I2 composite was successfully prepared insitu via the thermal treatment of a g-C3N4/Bi OI precursor at 400°C for 3 hr.The as-prepared g-C3N4/Bi4O5I2 showed high phot...A graphite carbon nitride(g-C3N4)modified Bi4O5I2 composite was successfully prepared insitu via the thermal treatment of a g-C3N4/Bi OI precursor at 400°C for 3 hr.The as-prepared g-C3N4/Bi4O5I2 showed high photocatalytic performance in Methyl Orange(MO)degradation under visible light.The best sample presented a degradation rate of 0.164 min^-1,which is 3.2 and 82 times as high as that of Bi4O5I2 and g-C3N4,respectively.The g-C3N4/Bi4O5I2 was characterized by X-ray powder diffractometer(XRD),scanning electron microscopy(SEM),transmission electron microscopy(TEM),Raman,X-ray photoelectron spectroscopy(XPS),ultraviolet-visible diffuse reflectance spectra(DRS),electrochemical impedance spectroscopy(EIS)and transient photocurrent response in order to explain the enhanced photoactivity.Results indicated that the decoration with a small amount of g-C3N4 influenced the specific surface area only slightly.Nevertheless,the capability for absorbing visible light was improved measurably,which was beneficial to the MO degradation.On top of that,a strong interaction between g-C3N4 and Bi4O5I2 was detected.This interplay promoted the formation of a favorable heterojunction structure and thereby enhanced the charge separation.Thus,the g-C3N4/Bi4O5I2 composite presented greater charge separation efficiency and much better photocatalytic performance than Bi4O5I2.Additionally,g-C3N4/Bi4O5I2 also presented high stability.·O2^- and holes were verified to be the main reactive species.展开更多
3D flower-like hierarchical mesoporous Bi_(4)O_(5)I_(2)/MoS_(2)Z-scheme layered heterojunction photocatalyst was fabricated by oil bath and hydrothermal methods.The heterojunction with narrow band gap of~1.95 eV exten...3D flower-like hierarchical mesoporous Bi_(4)O_(5)I_(2)/MoS_(2)Z-scheme layered heterojunction photocatalyst was fabricated by oil bath and hydrothermal methods.The heterojunction with narrow band gap of~1.95 eV extended the photoresponse to near-infrared region,which showed obvious photothermal effect due to the introduction of MoS_(2) with broad spectrum response.MoS_(2) nanosheets were anchored onto the surface of flower-like hierarchical mesoporous Bi_(4)O_(5)I_(2) nanosheets,thereby forming efficient layered heterojunctions,the solar-driven photocatalytic efficiency in degradation of highly toxic dichlorophenol and reduction of hexavalent chromium was improved to 98.5%and 99.2%,which was~4 and 7 times higher than that of the pristine Bi_(4)O_(5)I_(2),respectively.In addition,the photocatalytic hydrogen production rate reached 496.78 μmol h^(-1)g^(-1),which was~6 times higher than that of the pristine Bi_(4)O_(5)I_(2).The excellent photocatalytic performance can be ascribed to the promoted photothermal effect,as well as,the formation of compact Z-scheme layered heterojunctions.The 3D flower-like hierarchical mesoporous structure provided adequate surface active-sites,which was conducive to the mass transfer.Moreover,the high stability of the prepared photocatalyst further promoted its potential practical application.This strategy also provides new insights for fabricating layered Zscheme heterojunctions photocatalysts with highly photothermal-photocatalytic efficiency.展开更多
基金financially supported by National Undergraduate Training Program for Innovation and Entrepreneurship(Nos.201810345012 and 201810345051)
文摘A graphite carbon nitride(g-C3N4)modified Bi4O5I2 composite was successfully prepared insitu via the thermal treatment of a g-C3N4/Bi OI precursor at 400°C for 3 hr.The as-prepared g-C3N4/Bi4O5I2 showed high photocatalytic performance in Methyl Orange(MO)degradation under visible light.The best sample presented a degradation rate of 0.164 min^-1,which is 3.2 and 82 times as high as that of Bi4O5I2 and g-C3N4,respectively.The g-C3N4/Bi4O5I2 was characterized by X-ray powder diffractometer(XRD),scanning electron microscopy(SEM),transmission electron microscopy(TEM),Raman,X-ray photoelectron spectroscopy(XPS),ultraviolet-visible diffuse reflectance spectra(DRS),electrochemical impedance spectroscopy(EIS)and transient photocurrent response in order to explain the enhanced photoactivity.Results indicated that the decoration with a small amount of g-C3N4 influenced the specific surface area only slightly.Nevertheless,the capability for absorbing visible light was improved measurably,which was beneficial to the MO degradation.On top of that,a strong interaction between g-C3N4 and Bi4O5I2 was detected.This interplay promoted the formation of a favorable heterojunction structure and thereby enhanced the charge separation.Thus,the g-C3N4/Bi4O5I2 composite presented greater charge separation efficiency and much better photocatalytic performance than Bi4O5I2.Additionally,g-C3N4/Bi4O5I2 also presented high stability.·O2^- and holes were verified to be the main reactive species.
基金support of this research by the National Natural Science Foundation of China(21871078)the Natural Science Foundation of Heilongjiang Province(JQ2019B001 and B2018010)+3 种基金the Heilongjiang Postdoctoral Startup Fund(LBH-Q14135)the Heilongjiang University Science Fund for Distinguished Young Scholars(JCL201802)the Heilongjiang Provincial Institutions of Higher Learning Basic Research Funds Basic Research Projects(KJCX201909)the Heilongjiang Touyan Innovation Team Program.
文摘3D flower-like hierarchical mesoporous Bi_(4)O_(5)I_(2)/MoS_(2)Z-scheme layered heterojunction photocatalyst was fabricated by oil bath and hydrothermal methods.The heterojunction with narrow band gap of~1.95 eV extended the photoresponse to near-infrared region,which showed obvious photothermal effect due to the introduction of MoS_(2) with broad spectrum response.MoS_(2) nanosheets were anchored onto the surface of flower-like hierarchical mesoporous Bi_(4)O_(5)I_(2) nanosheets,thereby forming efficient layered heterojunctions,the solar-driven photocatalytic efficiency in degradation of highly toxic dichlorophenol and reduction of hexavalent chromium was improved to 98.5%and 99.2%,which was~4 and 7 times higher than that of the pristine Bi_(4)O_(5)I_(2),respectively.In addition,the photocatalytic hydrogen production rate reached 496.78 μmol h^(-1)g^(-1),which was~6 times higher than that of the pristine Bi_(4)O_(5)I_(2).The excellent photocatalytic performance can be ascribed to the promoted photothermal effect,as well as,the formation of compact Z-scheme layered heterojunctions.The 3D flower-like hierarchical mesoporous structure provided adequate surface active-sites,which was conducive to the mass transfer.Moreover,the high stability of the prepared photocatalyst further promoted its potential practical application.This strategy also provides new insights for fabricating layered Zscheme heterojunctions photocatalysts with highly photothermal-photocatalytic efficiency.
