Preparation And Photocatalytic Properties Of Graphene/TiO₂ Sandwich Composite

Energy crisis and environmental pollution are two major problems to be solved,thus the utilization of clear energy-solar energy is valued by researchers.The core is semiconductor photocatalyst.Recently years,graphene/TiO₂ composite photocatalyst have become a research hotspot.China is rich in graphite and titaniferous minerals,and the functional application of these mineral provides a new way for comprehensive utilization of resources.However,the supported graphene/TiO₂ composites have poor structure and performance stability,which limits their practical application.Herein,this study constructed graphene/TiO₂/X composite with sandwich strcture to solve above problems.Firstly,the theorical model and electronic structure of graphene/TiO₂/X were carried out with Material Studio with the based of density function theory.The band structure,Muliken population and density of states were calculated,which provided a theoretical basis for later experimental research.Then,two-step hydrothermal method,pre-intercalation-ion exchange-hydrothermal method,pre-intercalation-ion exchange-calcination methods were studied in preparatio n graphene/TiO₂/graphene,respectively.The graphene/TiO₂/graphene fabricated by pr e-intercalation-ion exchange-calcination method showed degradation rate towards CIP of 90%at the irradiation of 5 W LED visible light after 150 mins.Furtherly,the TiO₂ nanoarrays were prepared with Sn O₂ on FTO as template and the modification were studied by hydrothermal method.The continuous and uniform graphene films were formed on TiO₂ nanoarrays by ultrasonic spraying method.The graphene/TiO₂/Sn O₂ sample finally showed degradation rate towards CIP of 92%at the irradiation of 5 W LED visible light after 150 mins.Finally,graphene and TiO₂ formed a suitable energy band structure,which could enhance the adsorption properties and photogenerated electron transfer ability.Through the active species capture experiment,holes are the main active substances in the catalytic process of GO/TiO₂/X composite with sandwich structure.Pictures 104;Tables 7;References 102...