Herein,perylenetetracarboxylic acid(PTA)nanosheets with anisotropic charge migration driven by the formed internal electric fields are synthesized through a facile hydrolysis-reassembly process.Strategically,a Z-schem...Herein,perylenetetracarboxylic acid(PTA)nanosheets with anisotropic charge migration driven by the formed internal electric fields are synthesized through a facile hydrolysis-reassembly process.Strategically,a Z-scheme heterojunction with free-flowing interfacial charge transfer and spatially separated redox centers is constructed based on the distinct photogenerated electrons and holes accumulation regions of PTA nanosheets by in-situ introducing BiVO_(4)quantum dots(BQD)and nanosized Au.The optimized BQD/PTA-Au exhibits a ca.6.4-fold and 4.8-fold enhancement in H_(2)O_(2)production rate and apparent quantum yield at 405 nm compared with pristine PTA,respectively.The exceptional activities are attributed to the cascade Z-scheme charge transfer followed the matched charge migration orientation,as well as the Au active sites for accelerating 2e-oxygen reduction pathway induced by superoxide radicals,as unraveled by electron paramagnetic resonance,in-situ irradiated X-ray photoelectron spectroscopy and in-situ diffuse reflectance infrared Fourier transformation spectroscopy.This work provides a strategy to design an efficient Z-scheme system towards solar-driven H_(2)O_(2)production.展开更多
It is still challenging for exploring high-active photocatalysts to efficiently remove levofloxacin(LFX)by activating peroxymonosulfate(PMS).Herein,we constructed a novel Z scheme ZnFe_(2)O_(4)/g-C_(3)N_(4)/CQDs(ZCC)h...It is still challenging for exploring high-active photocatalysts to efficiently remove levofloxacin(LFX)by activating peroxymonosulfate(PMS).Herein,we constructed a novel Z scheme ZnFe_(2)O_(4)/g-C_(3)N_(4)/CQDs(ZCC)heterojunction by anchoring ZnFe_(2)O_(4)on tubular-like g-C_(3)N_(4)induced by CQDs(denoted as CNC)using microwave-assisted thermal methods.The ZCC exhibits the highest photocatalytic activity in activating PMS for LFX degradation,endowing a removal rate~95.3%,which is 4.8 and 7.3 times that of pure ZnFe_(2)O_(4)(19.8%)and g-C_(3)N_(4)(13.1%),separately.The enhanced photocatalytic activity of ZCC can be attributed to the distinctive morphology of CNC,enhanced light response,increased specific surface area and abundant pore structure.Besides,the formed Z scheme heterojunction and CQDs acting as a transmission bridge of the photogenerated charges(e−and h+)can accelerate transfer and inhibit recombination of e−and h+.Radical capture experiments and electron spin resonance(ESR)measurements revealed that SO4•-and O2•-play a predominant role in degradation process of LFX.Liquid chromatography-mass spectrometry(LC-MS)was applied to identify intermediates and propose feasible degradation pathways of LFX.In conclusion,this study presents a promising strategy for regulating the photocatalytic activity of g-C_(3)N_(4)by simultaneously integrating CQDs induction and Z scheme heterojunction construction.展开更多
文摘Herein,perylenetetracarboxylic acid(PTA)nanosheets with anisotropic charge migration driven by the formed internal electric fields are synthesized through a facile hydrolysis-reassembly process.Strategically,a Z-scheme heterojunction with free-flowing interfacial charge transfer and spatially separated redox centers is constructed based on the distinct photogenerated electrons and holes accumulation regions of PTA nanosheets by in-situ introducing BiVO_(4)quantum dots(BQD)and nanosized Au.The optimized BQD/PTA-Au exhibits a ca.6.4-fold and 4.8-fold enhancement in H_(2)O_(2)production rate and apparent quantum yield at 405 nm compared with pristine PTA,respectively.The exceptional activities are attributed to the cascade Z-scheme charge transfer followed the matched charge migration orientation,as well as the Au active sites for accelerating 2e-oxygen reduction pathway induced by superoxide radicals,as unraveled by electron paramagnetic resonance,in-situ irradiated X-ray photoelectron spectroscopy and in-situ diffuse reflectance infrared Fourier transformation spectroscopy.This work provides a strategy to design an efficient Z-scheme system towards solar-driven H_(2)O_(2)production.
基金Project(32272823) supported by the National Natural Science Foundation of ChinaProject(145309315) supported by the Research Foundation of Education Bureau of Heilongjiang Province of ChinaProject(YSTSXK202309) supported by the Plant Food Processing Technology Advantages Characteristic Discipline “Science and Technology Research” Special Project in Heilongjiang Province,China。
文摘It is still challenging for exploring high-active photocatalysts to efficiently remove levofloxacin(LFX)by activating peroxymonosulfate(PMS).Herein,we constructed a novel Z scheme ZnFe_(2)O_(4)/g-C_(3)N_(4)/CQDs(ZCC)heterojunction by anchoring ZnFe_(2)O_(4)on tubular-like g-C_(3)N_(4)induced by CQDs(denoted as CNC)using microwave-assisted thermal methods.The ZCC exhibits the highest photocatalytic activity in activating PMS for LFX degradation,endowing a removal rate~95.3%,which is 4.8 and 7.3 times that of pure ZnFe_(2)O_(4)(19.8%)and g-C_(3)N_(4)(13.1%),separately.The enhanced photocatalytic activity of ZCC can be attributed to the distinctive morphology of CNC,enhanced light response,increased specific surface area and abundant pore structure.Besides,the formed Z scheme heterojunction and CQDs acting as a transmission bridge of the photogenerated charges(e−and h+)can accelerate transfer and inhibit recombination of e−and h+.Radical capture experiments and electron spin resonance(ESR)measurements revealed that SO4•-and O2•-play a predominant role in degradation process of LFX.Liquid chromatography-mass spectrometry(LC-MS)was applied to identify intermediates and propose feasible degradation pathways of LFX.In conclusion,this study presents a promising strategy for regulating the photocatalytic activity of g-C_(3)N_(4)by simultaneously integrating CQDs induction and Z scheme heterojunction construction.
