Preparation Of Silver Halide Nanocomposite Photocatalysts And Their Photodegradation Performance

With the development of economy,inflation of population and rapid increase of difficulty in discomposing organic pollutants,the limited water source was polluted seriously.How to solve this problem has been a worldwide concern.Meanwhile,the reducing fossil energy is threatening our daily life.AgX-based visible-light-responsive photocatalysts exhibit excellent photocatalytic activity.It can efficiently discompose pollutants in the water,and realize the conversion of solar energy to hydrogen energy.Further investigation of controlled synthesis and application of AgX-based photocatalyst is needed.The porous AgI/SiO₂ composite photocatalyst was synthesized by simple method.The core-shell structure AgI/SiO₂ was first prepared by one-pot method,then the porous AgI/SiO₂was etched with different concentrations of NaOH.Finally,the synthesis reaction of Ag and halogen was porous structure of AgI/SiO₂ composite photocatalyst.AgI/SiO₂ porous nanoparticles showed excellent visible light photocatalytic activity when degrading RhB,in which AgI/SiO₂-0.125 showed the highest photocatalytic activity,and the degradation efficiency reached 98%in 25 minutes.At the same time,the fourth cycle use all maintain a high catalytic activity and stability.The above characteristics of the porous AgI/SiO₂composite photocatalyst has potential prospects in water purification and environmental management.We prepared the AgI/poly dopamine composite nanometer photocatalyst with yolk-shell structure,and characterized the composition,structure and morphology of the product.First,Ag/SiO₂/poly dopamine was prepared by etching the intermediate layer of silica to obtain the egg yolk-shell structure of Ag/poly dopamine and finally Ag is used to react directly with the halogen reaction of the yolk-shell AgI/poly dopamine complex nano catalyst of light.AgI poly dopamine nanoparticles showed excellent visible light photocatalytic activity,and the first degradation efficiency reached 95%in 40 minutes.Yolk-shell structure AgI/poly dopamine nanoparticles are viewed as some kind of effective and stable visible light photocatalysts for the decolorization of RhB molecules.This work provides a way for the morphology control of AgX nanoparticles.The PAN fiber was prepared by electrospinning,then the Ag nanoparticles were supported on the surface of the fiber membrane by halogen plating to PAN/Ag/AgX composite nanofibers by electroless plating.The composite fiber membranes of silver halide or AgX/Ag nanoparticles loaded with polyacrylonitrile nanofibers were prepared by adjusting the amount of halogen element.The prepared nanofibers exhibit excellent photocatalytic activity and long-term stability under visible light,which can be easily separated from the liquid after the photocatalytic reaction.Our PAN/Ag/AgX hybrid nanofibers are used as kinds of effective and stable visible light photocatalysts for the decolorization of RhB molecules.Although this study only covers PAN/Ag/AgI and PAN/Ag/AgBr systems,we believe that this method can also be applied to the preparation of other silver halide semiconducting heterostructures and may be promising in photocatalytic and photoelectric conversion application.