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
以钛酸四丁酯、乙酸钡和乙醇为原料,分别以Fe(N O 3)3.9H 2O和La(N O 3)3.6H 2O为Fe3+和La3+源。按照化学配比式(Ba1-3xLa2x)(Ti1-3xFe4x)O 3(x=0.0025、0.005、0.0075、0.01)的要求设计试样组成。采用溶胶-凝胶法制备了Fe3+/La3+共同掺...以钛酸四丁酯、乙酸钡和乙醇为原料,分别以Fe(N O 3)3.9H 2O和La(N O 3)3.6H 2O为Fe3+和La3+源。按照化学配比式(Ba1-3xLa2x)(Ti1-3xFe4x)O 3(x=0.0025、0.005、0.0075、0.01)的要求设计试样组成。采用溶胶-凝胶法制备了Fe3+/La3+共同掺杂BaTiO 3粉体。分析讨论了工艺参数(pH、温度)对掺杂La3+/Fe3+BaTiO 3溶胶凝胶体系的影响。在1250～1300℃烧结(Ba1-3xLa2x)(Ti1-3xFe4x)O 3陶瓷,发现随着掺杂量的增加,相应的烧结温度随之上升。用TEM、SEM、X R D等手段对微观结构和组成进行了分析。组成为(Ba0.9925La0.005)(Ti0.9925Fe0.01)O 3时,在1260～1280℃烧结2h下,可以使得致密度较高;颗粒粒径在1μm左右,在0～80℃温度范围内1,kH z测试频率下可以获得介电系数为2800,电容变化率△C/C25℃为1%的BaTiO 3陶瓷。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 National 863 Program Emphasis Project (Nanometer Biology Ware Study, No.2007AA0222006)National Natural Science Foundation of P.R. China(No.30740062 and No.30872970)High School Doctor Subjec Special-purpose Scientific Research Foundation(No.20070286042)
