Rapid recombination of charge carriers and sluggish Cu^(2+)/Cu^(+)conversion rate in Cu-based photocatalysts hinder the improvement of the peroxymonosulfate(PMS)activation efficiency.Herein,a novel S-scheme system was...Rapid recombination of charge carriers and sluggish Cu^(2+)/Cu^(+)conversion rate in Cu-based photocatalysts hinder the improvement of the peroxymonosulfate(PMS)activation efficiency.Herein,a novel S-scheme system was successfully built through hydrothermal and in-situ calcination methods to activate PMS for norfloxacin(NOR)degradation,which combined CuO with BiVO_(4)(BVO)containing surface heterojunc-tion.The UV-vis spectra manifested that BVO displayed excellent visible light absorption performance after compounding with CuO,and the light absorption threshold of CuO/BVO was about 600 nm.Thanks to the existence of surface heterojunction in BVO,the photoinduced electrons,and holes would trans-fer to{010}and{110}facets,respectively.The construction of S-scheme heterojunction further facilitated the accumulation of electrons on CuO,thus realizing the spatial separation of charge carriers.In addi-tion,the electrons gathered on the CuO expedited the Cu^(2+)/Cu^(+)cycle,thereby improving the activation efficiency of PMS.On this basis,the NOR removal capacity of 5CuO/BVO composites was obviously en-hanced,which was 3.65 and 2.45 times that of CuO and BVO.Moreover,the influence of ambient pH and PMS dosage on the photocatalytic performance of CuO/BVO was investigated.Through the analysis of NOR degradation pathways and degradation products,it was found that the toxicity threat of NOR to the environment was reduced during the degradation process.According to the XPS results,forming the S-scheme heterojunction accelerated the Cu^(2+)/Cu^(+)redox cycle during the PMS activating process.Meanwhile,photoluminescence(PL)and time-resolved photoluminescence(TRPL)analysis demonstrated that the CuO/BVO composites exhibited eminent ability for charge separation.The possible mechanism of charge transfer was assumed by exploring reactive species and the energy band structure of catalysts.To sum up,this research provides a new perspective on boosting PMS activation to purify antibiotics in water.展开更多
基金the financial support of this work from the National Natural Science Foundation of China(Grant No.22172064)National Laboratory of Solid State Microstructures,Nanjing University(Grant No.M34047)+1 种基金Project of Wuxi Science and Technology Development Fund(Grant No.Y20212004)Prof.Haifeng Shi was indebted to the financial support from the Qing Lan Project of Jiangsu Province.
文摘Rapid recombination of charge carriers and sluggish Cu^(2+)/Cu^(+)conversion rate in Cu-based photocatalysts hinder the improvement of the peroxymonosulfate(PMS)activation efficiency.Herein,a novel S-scheme system was successfully built through hydrothermal and in-situ calcination methods to activate PMS for norfloxacin(NOR)degradation,which combined CuO with BiVO_(4)(BVO)containing surface heterojunc-tion.The UV-vis spectra manifested that BVO displayed excellent visible light absorption performance after compounding with CuO,and the light absorption threshold of CuO/BVO was about 600 nm.Thanks to the existence of surface heterojunction in BVO,the photoinduced electrons,and holes would trans-fer to{010}and{110}facets,respectively.The construction of S-scheme heterojunction further facilitated the accumulation of electrons on CuO,thus realizing the spatial separation of charge carriers.In addi-tion,the electrons gathered on the CuO expedited the Cu^(2+)/Cu^(+)cycle,thereby improving the activation efficiency of PMS.On this basis,the NOR removal capacity of 5CuO/BVO composites was obviously en-hanced,which was 3.65 and 2.45 times that of CuO and BVO.Moreover,the influence of ambient pH and PMS dosage on the photocatalytic performance of CuO/BVO was investigated.Through the analysis of NOR degradation pathways and degradation products,it was found that the toxicity threat of NOR to the environment was reduced during the degradation process.According to the XPS results,forming the S-scheme heterojunction accelerated the Cu^(2+)/Cu^(+)redox cycle during the PMS activating process.Meanwhile,photoluminescence(PL)and time-resolved photoluminescence(TRPL)analysis demonstrated that the CuO/BVO composites exhibited eminent ability for charge separation.The possible mechanism of charge transfer was assumed by exploring reactive species and the energy band structure of catalysts.To sum up,this research provides a new perspective on boosting PMS activation to purify antibiotics in water.
