Metal-organic frameworks (MOFs)-based composites have been widely applied as photocatalysts because of their synergistic effect between the two individual component.Herein,TiO_(2)@NH_(2)-MIL-125(Ti) nanocomposites whi...Metal-organic frameworks (MOFs)-based composites have been widely applied as photocatalysts because of their synergistic effect between the two individual component.Herein,TiO_(2)@NH_(2)-MIL-125(Ti) nanocomposites which possess unsaturated titanium–oxo clusters,mesoporous structure,and intimate interface were successfully constructed via an in-situ distilled water-etched route.The X-ray photoelectron spectroscopy (XPS) measurements indicated strong electronic interaction between TiO_(2)and NH_(2)-MIL-125(Ti),confirming the formation of TiO 2@NH_(2)-MIL-125(Ti) nanocomposite.Photoelectrochemical and thermodynamics measurements showed that TiO_(2)@NH_(2)-MIL-125(Ti)nanocomposites have improved charge separation efficient and decreased transfer resistance of the carriers within the heterojunction interfaces,which facilitates the photoexcited electrons transfer and reduction of the Cr(VI) species.Therefore,the optimal TiO_(2)@NH_(2)-MIL-125(Ti)nanocomposite demonstrated superior performance compared to NH_(2)-MIL-125(Ti) and NH_(2)-MIL-125(Ti) derived TiO_(2).Based on the free radical trapping experiment and electron paramagnetic resonance (EPR) measurements,a possible type-II scheme was proposed for the enhanced photocatalytic activity over the TiO_(2)@NH_(2)-MIL-125(Ti) nanocomposite.展开更多
Novel graphitic carbon nitride(g-C_(3)N_(4))nanosheet/Bi_(5)O_(7)Br/NH_(2)-MIL-88B(Fe)photocatalysts(denoted as GCN-NSh/Bi_(5)O_(7)Br/FeMOF,in which MOF is metal–organic framework)with double S-scheme heterojunctions...Novel graphitic carbon nitride(g-C_(3)N_(4))nanosheet/Bi_(5)O_(7)Br/NH_(2)-MIL-88B(Fe)photocatalysts(denoted as GCN-NSh/Bi_(5)O_(7)Br/FeMOF,in which MOF is metal–organic framework)with double S-scheme heterojunctions were synthesized by a facile solvothermal route.The resultant materials were examined by X-ray photoelectron spectrometer(XPS),X-ray diffraction(XRD),scanning electron microscopy(SEM),energy dispersive X-ray spectroscopy(EDX),transmission electron microscopy(TEM),high-resolution transmission electron microscopy(HRTEM),photoluminescence spectroscopy(PL),Fourier transform infrared spectroscopy(FT-IR),UV-Vis diffuse reflection spectroscopy(UV-vis DRS),photocurrent density,electrochemical impedance spectroscopy(EIS),and Brunauer–Emmett–Teller(BET)analyses.After the integration of Fe-MOF with GCN-NSh/Bi_(5)O_(7)Br,the removal constant of tetracycline over the optimal GCN-NSh/Bi_(5)O_(7)Br/Fe-MOF(15wt%)nanocomposite was promoted 33 times compared with that of the pristine GCN.The GCN-NSh/Bi_(5)O_(7)Br/Fe-MOF(15wt%)nanocomposite showed superior photoactivity to azithromycin,metronidazole,and cephalexin removal that was 36.4,20.2,and 14.6 times higher than that of pure GCN,respectively.Radical quenching tests showed that·O_(2)-and h+mainly contributed to the elimination reaction.In addition,the nanocomposite maintained excellent activity after 4 successive cycles.Based on the developed n–n heterojunctions among n-GCN-NSh,n-Bi_(5)O_(7)Br,and n-Fe-MOF semiconductors,the double S-scheme charge transfer mechanism was proposed for the destruction of the selected antibiotics.展开更多
Photocatalysis is considered as an ideal strategy for water pollution treatment.However,it remains challenging to design a highly efficient photo-catalytic system through regulating the charge flow via a precise appro...Photocatalysis is considered as an ideal strategy for water pollution treatment.However,it remains challenging to design a highly efficient photo-catalytic system through regulating the charge flow via a precise approach.In this work,a novel NH2-MIL-125(Ti)/Bi2WO6 composite was constructed via self-assembly growing Bi2WO6 nanosheets on NH2-MIL-125(Ti)material.The characterization results demonstrated that NH2-MIL-125(Ti)was successfully incorporated into Bi2WO6 and the photoexcited carriers could be efficiently separated and transferred between the two components.NH2-MIL-125(Ti)/Bi2WO6 composites displayed enhanced photocatalytic activity for the removal of rhodamine B(RhB)and tetracycline(TC)under visible light irradiation,and the optimal weight ratio of NH2-MIL-125(Ti)was determined to be 7 wt%.The introduction of NH2-MIL-125(Ti)into Bi2WO6 could raise the absorption of visible light,accelerate the separation and transfer of charge carriers,and boost photocatalytic activity.This research presents a wide range of possibilities for the further development of novel composites in the field of environment purification.展开更多
基金financially supported by the National Natural Science Foundation of China (Nos. 61204078, 21671059, and 21877027)the Program for Innovative Research Team (in Science and Technology) of Henan Normal University (No. 2022TD03)+1 种基金the Henan Science and Technology Program (No. 21B150005)the Scientific and Technological Innovation Team of Henan Normal University (No. 2022TD03)。
文摘Metal-organic frameworks (MOFs)-based composites have been widely applied as photocatalysts because of their synergistic effect between the two individual component.Herein,TiO_(2)@NH_(2)-MIL-125(Ti) nanocomposites which possess unsaturated titanium–oxo clusters,mesoporous structure,and intimate interface were successfully constructed via an in-situ distilled water-etched route.The X-ray photoelectron spectroscopy (XPS) measurements indicated strong electronic interaction between TiO_(2)and NH_(2)-MIL-125(Ti),confirming the formation of TiO 2@NH_(2)-MIL-125(Ti) nanocomposite.Photoelectrochemical and thermodynamics measurements showed that TiO_(2)@NH_(2)-MIL-125(Ti)nanocomposites have improved charge separation efficient and decreased transfer resistance of the carriers within the heterojunction interfaces,which facilitates the photoexcited electrons transfer and reduction of the Cr(VI) species.Therefore,the optimal TiO_(2)@NH_(2)-MIL-125(Ti)nanocomposite demonstrated superior performance compared to NH_(2)-MIL-125(Ti) and NH_(2)-MIL-125(Ti) derived TiO_(2).Based on the free radical trapping experiment and electron paramagnetic resonance (EPR) measurements,a possible type-II scheme was proposed for the enhanced photocatalytic activity over the TiO_(2)@NH_(2)-MIL-125(Ti) nanocomposite.
文摘Novel graphitic carbon nitride(g-C_(3)N_(4))nanosheet/Bi_(5)O_(7)Br/NH_(2)-MIL-88B(Fe)photocatalysts(denoted as GCN-NSh/Bi_(5)O_(7)Br/FeMOF,in which MOF is metal–organic framework)with double S-scheme heterojunctions were synthesized by a facile solvothermal route.The resultant materials were examined by X-ray photoelectron spectrometer(XPS),X-ray diffraction(XRD),scanning electron microscopy(SEM),energy dispersive X-ray spectroscopy(EDX),transmission electron microscopy(TEM),high-resolution transmission electron microscopy(HRTEM),photoluminescence spectroscopy(PL),Fourier transform infrared spectroscopy(FT-IR),UV-Vis diffuse reflection spectroscopy(UV-vis DRS),photocurrent density,electrochemical impedance spectroscopy(EIS),and Brunauer–Emmett–Teller(BET)analyses.After the integration of Fe-MOF with GCN-NSh/Bi_(5)O_(7)Br,the removal constant of tetracycline over the optimal GCN-NSh/Bi_(5)O_(7)Br/Fe-MOF(15wt%)nanocomposite was promoted 33 times compared with that of the pristine GCN.The GCN-NSh/Bi_(5)O_(7)Br/Fe-MOF(15wt%)nanocomposite showed superior photoactivity to azithromycin,metronidazole,and cephalexin removal that was 36.4,20.2,and 14.6 times higher than that of pure GCN,respectively.Radical quenching tests showed that·O_(2)-and h+mainly contributed to the elimination reaction.In addition,the nanocomposite maintained excellent activity after 4 successive cycles.Based on the developed n–n heterojunctions among n-GCN-NSh,n-Bi_(5)O_(7)Br,and n-Fe-MOF semiconductors,the double S-scheme charge transfer mechanism was proposed for the destruction of the selected antibiotics.
基金This work was financially supported by the National Natural Science Foundation of China(Nos.21476098,21471069 and 21576123)and Jiangsu University Scientific Research Funding(No.11JDG0146).
文摘Photocatalysis is considered as an ideal strategy for water pollution treatment.However,it remains challenging to design a highly efficient photo-catalytic system through regulating the charge flow via a precise approach.In this work,a novel NH2-MIL-125(Ti)/Bi2WO6 composite was constructed via self-assembly growing Bi2WO6 nanosheets on NH2-MIL-125(Ti)material.The characterization results demonstrated that NH2-MIL-125(Ti)was successfully incorporated into Bi2WO6 and the photoexcited carriers could be efficiently separated and transferred between the two components.NH2-MIL-125(Ti)/Bi2WO6 composites displayed enhanced photocatalytic activity for the removal of rhodamine B(RhB)and tetracycline(TC)under visible light irradiation,and the optimal weight ratio of NH2-MIL-125(Ti)was determined to be 7 wt%.The introduction of NH2-MIL-125(Ti)into Bi2WO6 could raise the absorption of visible light,accelerate the separation and transfer of charge carriers,and boost photocatalytic activity.This research presents a wide range of possibilities for the further development of novel composites in the field of environment purification.
基金supported by the National Key R&D Program of China(No.2017YFA0207202)the National Natural Science Foundation of China(No.51572263,No.51772299,No.41701259).