Preparation And Photocatalytic Performance Of CU2O/CUS Composite Photocatalytic Films

With the steady development of social economy and the acceleration of industrial processes,the discharge of industrial and domestic sewage make water pollution a major pollution source.Water treatment is the priority in improving the environment,and traditional biological treatment technology and physical processing technology can't keep up with the needs of social development.Hence,the development and utilization of new energy sources are urgent with the increasing demand for energy.The combination of new energy utilization and sewage treatment have become the study direction of many scholars and experts.The emergence of photocatalytic technology provides a bridge for the combination,and the reaction conditions of photocatalytic technology are more moderate and the photocatalyst has high degradation efficiency for pollutant.Among them,the research of Cu2O has gradually matured,due to the high catalytic activity,strong oxidation ability and use of visible light.However,Cu2O is unstable and easily inactivated during the degradation of organic pollutants,its photoelectric conversion efficiency is only 1/10 of the theoretical conversion efficiency.And the powder catalyst during the reaction process is extremely easy to lose,which causes the secondary pollution.It would be more realistic and economical to develop a catalyst,which is not easily lost,without secondary pollution and effectively utilize solar energy.Based on this idea,we prepared the photocatalytic Cu2O/CuS composite film by a orthogonal experimental,and the index is the degradation rate of MO dye on Cu2O/CuS composite photocatalyst film.The optimum technological parameters are as follows:the reaction solution concentration is 0.02 mol/L,the reaction temperature is 180 ? and the reaction time is 12 h in the first step.The mass of thiourea is 0.02 g,the reaction temperature is 150 ? and the reaction time is 12 h in the second step.The surface morphology and formation mechanism of Cu2O/CuS composite photocatalytic films are investigated by SEM,EDX,XRD,HRTEM,FT-IR and so on.It can be determined that the Cu2O/CuS composite photocatalytic film with heterojunction structure is based on the Cu2O single layer film.The composite material has the uniform particles and flat films.Besides,the photocatalytic performance of Cu2O/CuS composite photocatalytic films for methyl orange dye(MO)was investigated.The results of single catalyst and composite catalyst photocatalytic performance comparison show that the Cu2O/CuS compound photocatalytic film has more efficient photocatalytic performance.The photocatalytic ability of the composite film can be greatly improved by participating in the reaction of light and H2O2.The stability of the film is superior,and the photocatalytic efficiency is unchanged after three cyclic reactions.The Cu2O/CuS composite photocatalyst film after ultrasonic treatment can completely degraded MO after 130 min reaction,and the composite film has higher mechanical strength.Mixed dye degradation tests show that the composite photocatalytic film still has a higher photocatalytic degradation in complex systems.