A novel p‐n heterostructure photocatalyst m‐Bi2O4/BiOCl was successfully synthetized through a facile ion‐etching method.Via adjusting the added volume of HCl solution,a series of different ratios of composite phot...A novel p‐n heterostructure photocatalyst m‐Bi2O4/BiOCl was successfully synthetized through a facile ion‐etching method.Via adjusting the added volume of HCl solution,a series of different ratios of composite photocatalysts were obtained.The as‐prepared samples of physical,chemical and optical characteristics were examined by X‐ray diffraction,scanning electron microscope,transmission electron microscope,energy dispersive X‐ray spectroscopy,selected‐area electron diffraction,Fourier transform infrared absorption,Raman microscope,N2 adsorption‐desorption,X‐ray photoelectron spectroscopy and UV‐vis spectrum technologies.The photocatalysts showed high degradation rate and complete mineralization ability for methyl orange and tetracycline solution under visible light.The reaction rate constant of m‐Bi2O4/BiOCl for methyl orange was 52.28 times higher than that of BiOCl.The characterization presented a good stability of materials.Furthermore,the photocurrent response test certified that the heterostructure effectively accelerated the separation and migration of photo‐generated carries.The scavenger experiments evidenced that hole(h+)and superoxide radical(?O2?)were the primary active radicals.A possible photocatalytic mechanism was proposed.This work provided an alternative photocatalyst applied to water environmental remediation.展开更多
The photocatalytic ability of ZnO is improved through the addition of flower‐like Bi2WO6 to prepare a Bi2WO6/ZnO composite with visible light activity.The composite is characterized by X‐ray diffraction,transmission...The photocatalytic ability of ZnO is improved through the addition of flower‐like Bi2WO6 to prepare a Bi2WO6/ZnO composite with visible light activity.The composite is characterized by X‐ray diffraction,transmission electron microscopy,scanning electron microscopy with UV–vis diffuse reflectance spectroscopy,X‐ray photoelectron spectroscopy and N2 adsorption‐desorption isotherms.After modification,the band gap energy of Bi2WO6/ZnO is reduced from 3.2 eV for ZnO to 2.6 eV.Under visible light irradiation,the Bi2WO6/ZnO composite shows an excellent photocatalytic activity for degrading methylene blue(MB)and tetracycline.The photo‐degradation efficiencies of(0.3:1)Bi2WO6/ZnO for MB and tetracycline are approximately 246 and 4500 times higher than those of bare ZnO,respectively,and correspondingly,the photo‐degradation rates for the two pollutants are approximately 120 and 200 times higher than those with bare ZnO,respectively.Moreover,the photocatalyst of(0.3:1)Bi2WO6/ZnO exhibits a higher transient photocurrent density of approximately 4.5μA compared with those of bare Bi2WO6 and ZnO nanoparticles.The successful recombination of Bi2WO6 and ZnO enhances the photocatalytic activity and reduces the band gap energy of ZnO,which can be attributed to the effective separation of electron–hole pairs.Active species trapping experiments display that[O2]-is the major species involved during photocatalysis rather than·OH and h+.This study provides insight into designing a meaningful visible‐light‐driven photocatalyst for environmental remediation.展开更多
基金supported by the National Natural Science Foundation of China(51578354)Suzhou Science and Technology Bureau(SS201667)+1 种基金Six Talent Peaks Program(2016-JNHB-067)Qing Lan Project of Jiangsu Province~~
文摘A novel p‐n heterostructure photocatalyst m‐Bi2O4/BiOCl was successfully synthetized through a facile ion‐etching method.Via adjusting the added volume of HCl solution,a series of different ratios of composite photocatalysts were obtained.The as‐prepared samples of physical,chemical and optical characteristics were examined by X‐ray diffraction,scanning electron microscope,transmission electron microscope,energy dispersive X‐ray spectroscopy,selected‐area electron diffraction,Fourier transform infrared absorption,Raman microscope,N2 adsorption‐desorption,X‐ray photoelectron spectroscopy and UV‐vis spectrum technologies.The photocatalysts showed high degradation rate and complete mineralization ability for methyl orange and tetracycline solution under visible light.The reaction rate constant of m‐Bi2O4/BiOCl for methyl orange was 52.28 times higher than that of BiOCl.The characterization presented a good stability of materials.Furthermore,the photocurrent response test certified that the heterostructure effectively accelerated the separation and migration of photo‐generated carries.The scavenger experiments evidenced that hole(h+)and superoxide radical(?O2?)were the primary active radicals.A possible photocatalytic mechanism was proposed.This work provided an alternative photocatalyst applied to water environmental remediation.
基金supported by the National Natural Science Foundation of China(51578354)Six Talent Peaks Program(2016-JNHB-067)+1 种基金Suzhou Science and Technology Bureau(SS201667)Qing Lan Project and Research Innovation Project for College Graduates of Jiangsu Province(KYCX17_2067)~~
文摘The photocatalytic ability of ZnO is improved through the addition of flower‐like Bi2WO6 to prepare a Bi2WO6/ZnO composite with visible light activity.The composite is characterized by X‐ray diffraction,transmission electron microscopy,scanning electron microscopy with UV–vis diffuse reflectance spectroscopy,X‐ray photoelectron spectroscopy and N2 adsorption‐desorption isotherms.After modification,the band gap energy of Bi2WO6/ZnO is reduced from 3.2 eV for ZnO to 2.6 eV.Under visible light irradiation,the Bi2WO6/ZnO composite shows an excellent photocatalytic activity for degrading methylene blue(MB)and tetracycline.The photo‐degradation efficiencies of(0.3:1)Bi2WO6/ZnO for MB and tetracycline are approximately 246 and 4500 times higher than those of bare ZnO,respectively,and correspondingly,the photo‐degradation rates for the two pollutants are approximately 120 and 200 times higher than those with bare ZnO,respectively.Moreover,the photocatalyst of(0.3:1)Bi2WO6/ZnO exhibits a higher transient photocurrent density of approximately 4.5μA compared with those of bare Bi2WO6 and ZnO nanoparticles.The successful recombination of Bi2WO6 and ZnO enhances the photocatalytic activity and reduces the band gap energy of ZnO,which can be attributed to the effective separation of electron–hole pairs.Active species trapping experiments display that[O2]-is the major species involved during photocatalysis rather than·OH and h+.This study provides insight into designing a meaningful visible‐light‐driven photocatalyst for environmental remediation.
