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
Core-shell TiO2-based photocatalysts with specific composition,morphology,and functionality have attracted considerable attention for their excellent degradation properties on organic pollutants via a photocatalytic o...Core-shell TiO2-based photocatalysts with specific composition,morphology,and functionality have attracted considerable attention for their excellent degradation properties on organic pollutants via a photocatalytic oxidation process.Herein,a N-TiO2@NH2-MIL-88(Fe)core-shell structure was prepared by coating NH2-MIL-88(Fe)on nitrogen-doped TiO2(N-TiO2)nanoparticles.Introduction of heteroatom nitrogen to pure TiOz expands the spectra response range,leading to enhanced quantum efficiency of photocatalyst.Furthermore.loading NH2-MIL-88(Fe)or N-TiOz improved the adsorption ability of the nanocomposites due to the porous tunnels of NH2-MIL-88(Fe).The resulted core-shell N-TiO2@NH2-MIL-88(Fe)nanocomposites realized the transfer of photo excited electrons from N-TiOz to NH2-MIL-88(Fe)rapidly,partially reduced Fe to Fe^2+in NH^2+MIL-88(Fe),and further enhanced the Fenton effect on efficiently degrading methylene blue dye(MB)under visible light(>420 nm)with the assistance of H2O2.展开更多
Nanometer blocks of amide-functionalized Fe(Ⅲ)-based metal-organic frameworks,NH2-MIL-53(Fe),were prepared via ultrasonic method without any surfactants at room temperature and atmospheric pressure.The characterizati...Nanometer blocks of amide-functionalized Fe(Ⅲ)-based metal-organic frameworks,NH2-MIL-53(Fe),were prepared via ultrasonic method without any surfactants at room temperature and atmospheric pressure.The characterization for the as-prepared nano-structured MOFs was established by XRD,SEM,TEM,XPS and N2 adsorption-desorption.The as-prepared sample with high specific surface area(179.9 m^(2)·g^(-1))showed excellent adsorption for methylene blue in the liquid phase.The as-prepared NH_(2)-MIL-53(Fe)adsorbent seems to be a promising material in practice for organic dye removal from aqueous solution.展开更多
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Supported by the National Natural Science Foundation of China(Nos.52071027,51872025)the National Key Research anc Development Program of China(No.2016YFB0701100)+1 种基金National Key Research and Development H863 Program of China(No.18H86303ZT0032702)the Fundamental Research Funds for the Central Universities of China(Nos.FRF-GF-20-03A FRF-GF-19-006B)。
文摘Core-shell TiO2-based photocatalysts with specific composition,morphology,and functionality have attracted considerable attention for their excellent degradation properties on organic pollutants via a photocatalytic oxidation process.Herein,a N-TiO2@NH2-MIL-88(Fe)core-shell structure was prepared by coating NH2-MIL-88(Fe)on nitrogen-doped TiO2(N-TiO2)nanoparticles.Introduction of heteroatom nitrogen to pure TiOz expands the spectra response range,leading to enhanced quantum efficiency of photocatalyst.Furthermore.loading NH2-MIL-88(Fe)or N-TiOz improved the adsorption ability of the nanocomposites due to the porous tunnels of NH2-MIL-88(Fe).The resulted core-shell N-TiO2@NH2-MIL-88(Fe)nanocomposites realized the transfer of photo excited electrons from N-TiOz to NH2-MIL-88(Fe)rapidly,partially reduced Fe to Fe^2+in NH^2+MIL-88(Fe),and further enhanced the Fenton effect on efficiently degrading methylene blue dye(MB)under visible light(>420 nm)with the assistance of H2O2.
基金Supported by the Fujian Provincial Key Laboratory of ecotoxicological effects and Control of New pollutants(PY19001)the Innovation and Entrepreneurship training Program for College students in 2019(201910402063)。
文摘Nanometer blocks of amide-functionalized Fe(Ⅲ)-based metal-organic frameworks,NH2-MIL-53(Fe),were prepared via ultrasonic method without any surfactants at room temperature and atmospheric pressure.The characterization for the as-prepared nano-structured MOFs was established by XRD,SEM,TEM,XPS and N2 adsorption-desorption.The as-prepared sample with high specific surface area(179.9 m^(2)·g^(-1))showed excellent adsorption for methylene blue in the liquid phase.The as-prepared NH_(2)-MIL-53(Fe)adsorbent seems to be a promising material in practice for organic dye removal from aqueous solution.
