Study On TiO₂/Fe₂O₃-g-C₃N₄ Photocatalysis/Photocatalytic Fuel Cell

With the increasing attention to environmental problems,sewage disposal has become the focus of scientific researchers.Photocatalysis(PC)has attracted much attention because of its low cost,high treatment efficiency and no further pollution.This technology could generate highly oxidizing holes(h+),hydroxyl radicals(·OH),superoxide radicals(O2·-)and other active particles,the organic pollutants were degraded and mineralized to small inorganic molecules such as CO2 and H2O.Photocatalytic fuel cell(PFC)can combine the technology of Photocatalysis and Fuel Cell(FC),converting solar energy and chemical energy into electric energy.In the meantime,it could also degrade organic pollutants,which provides a practical way to treat wastewater and solve energy crisis.Therefore,it is significant to develop new high efficiency photocatalyst.This paper makes a preliminary study on it,and the details of this thesis are as follows:1.g-C3N4 porous material were successfully synthesized by solvothermal polymerization.In order to improve the low rate of photo generated charge,separation of gC3N4,TiO2(TiO2)and Fe2O3(Fe2O3)were combined with g-C3N4 to prepare TiO2-g-C3N4 and Fe2O3-g-C3N4 photocatalysts.It is shown that the proper amount of TiO2 and Fe2O3 can significantly enhance the adsorption capacity of the catalyst and improve the rate of photogenerated charge separation.2.The common organic contaminants pollutants,such as Rhodamine B(RhB),Methyl Orange(MO)and Tetracycline(TC)was studied.The degradation properties of TiO2-g-C3N4 and Fe2O3-g-C3N4 on PC were evaluated.Results show that the g-C3N4-based photocatalyst prepared with TiO2 and Fe2O3 has good PC degradation performance under visible light irradiation,the PC performance is affected by the concentration of organic compound,hydrogen peroxide(H2O2)and the kind of organic compound.3.Fe2O3-g-C3N4 thin film electrode was prepared through drop coating solution,and it was assembled with Pt to make planer PFC.The degradation of RhB by Fe2O3-g-C3N4 thin film electrode under different conditions was compared,and the factors affecting the performance of Fe2O3-g-C3N4 thin film electrode PFC were studied.It was confirmed that the distance between the cathode and the anode,the concentration of RhB and H2O2 could all affect the degradation of organic compounds.4.The mechanism of degrading organic pollutants by PC with TiO2/Fe2O3-g-C3N4 photocatalyst and Fe2O3-g-C3N4 film electrode was analyzed by first-order Kinetic Model and active particle trapping experiment.It was confirmed once again that hole(h+)and hydroxyl radical(·OH)are main active particles causing the degradation of RhB,and the film electrode made of Fe2O3-g-C3N4 does not affect the dominant position of h+and·OH in the degradation process.