Preparation And Properties Of Bismuth Oxychloride Based Composite Photocatalyst

As a semiconductor photocatalytic material,bismuth oxychloride（Bi OCl）has been widely used in environmental protection and energy conversion.This paper mainly uses hydrothermal method to prepare Bi OCl photocatalyst under different hydrothermal temperatures,and then selects graphite phase nitrogen carbide（g-C₃N₄）and graphene oxide（GO）as modifier,according to different composite ways and different ratios,synthesis of Bi OCl composite materials.Using Rhodamine B（Rh B）,methylene blue（MB）and methyl orange（MO）as degradation targets,the photocatalytic activities of Bi OCl and the composites were investigated.Using Rhodamine B（Rh B）,methylene blue（MB）and methyl orange（MO）as degradation targets,the photocatalytic activities of Bi OCl and the composites were investigated.The Bi OCl and the composite were characterized by scanning electron microscopy,energy spectrum,X-ray diffraction,UV-VIS diffuse reflection spectrum,fluorescence emission spectrum and physical adsorption spectrometer.Draw the following conclusions:（1）Bi OCl was prepared by hydrothermal method.It was found that the photocatalytic activity of Bi OCl could be enhanced by increasing the hydrothermal temperature appropriately.The degradation efficiency of Rh B by Bi OCl prepared at 180℃was 98.09%,and the photoreaction rate constant was 1.44 times that of Bi OCl prepared at 120℃.（2）Loading g-C₃N₄ onto Bi OCl by aging method,calcination method,solvothermal method and physical agitation method respectively showed that the addition of g-C₃N₄ and appropriate composite method could improve the photocatalytic activity of Bi OCl.The degradation efficiencies of Rh B,MB and MO of g-C₃N₄/Bi OCl synthesized by physical agitation method were 95.11%,60.82%and 52.10%,respectively,after the simulated visible light irradiation for 120min.The photoreaction rate constants of g-C₃N₄/Bi OCl prepared by aging method,calcination method and solvothermal method are 4.5 times,1.4 times and 1.3times.（3）Different amounts of g-C₃N₄were added to Bi OCl by physical agitation method.When the mass fraction of g-C₃N₄ was 10%,the photocatalytic activity of g-C₃N₄/Bi OCl was the best,and the degradation efficiency of Rh B was 97.23%after 40min of simulated visible light irradiation,and the degradation effect of MB and MO was also certain.The photoreaction rate constant is 1.7 times,1.3 times,1.4 times and 1.5 times of the mass fraction of g-C₃N₄/Bi OCl prepared by 5%,15%,20%and 25%.（4）Different amounts of GO were added to the photocatalysts with the best photocatalytic activity in（3）by ultrasonic-assisted method.It was found that with the increase of GO,the photocatalytic activity of Bi OCl firstly increased and then decreased,and it had a good degradation effect on Rh B and MB.When the mass fraction of GO is 2%,the photocatalytic performance of r GO/CN/Bi OCl composite is the best,and it can degrade97.14%of Rh B and 93.87%of MB under the simulated visible light irradiation for 85min.The photoreaction rate constants are 2.9 times of pure Bi OCl and 1.61 times of 10%g-C₃N₄/BiOCl.