The Study On The Preparation And Photoelectric Property Of Nano Cu₂O-WO₃

Cu2O is an important p-type semiconductor, Its band gap only is 2.17eV. it also can degrade the organics and photolysis the water effectively in the range of visible light. In addition,the Cu2O can be prepared easily,no-toxic and cheap, it becoming the research highlight in photocatalytic field.it also is a very promising semiconductor material.However,the Cu2O had two deficiencies as a photocatalytic material. on the one hand the holes and eletrons generated from curpous oxide are easy to complex, leading to its photocatalytic is low. On the other hand, the stability of cuprous is poor, vulnerable in the process of photocatalytic oxidation of lead to changes in the oxidation of copper properties. In this article, we improve the photocatalytic activity of Cu2O and stability. through semiconductor compound and reduce Cu2O grain size.The results of Cu2O-WO3 thin film show that:Comparing to the cuprous film,the photocurrent density and carrier concentration of composite film has greatly enhanced. In addition,the photocurrent density of the film increased with the increased of doping amount. In the doping amount of 40g/L, photocurrent density of the film, the carrier concentration reaches the maximum, were 0.011mA/cm2 and 1 X 1019. the film also has good stability, the photocurrent density of the film can retain 80% of initial density after irradiating for 20 min.The results of nano Cu2O show that the morphology of cuprous oxide is nanorod, the diameter of nanrod is about 10nm. After annealing the sample, the photocurrent density, carrier concentration have been raised. At annealing temperature of 350℃, the current density of the sample, the maximum carrier concentration, respectively, 0.042 mA/cm2 and 1.4×1021/cm3, and the film has good stability.The results of nano Cu2O-WO3 show that the morphology of cuprous oxide is nanospindle. After annealing the samples, the largest of the photocurrent density and carrier concentration were 1.5mA/cm2and 4.8×1022.Photocatalytic activity of nano Cu2O-WO3 thin films increased, on the one hand is because of p-n semiconductor composite, lowered the degree of composite electronic-hole, improve the photocatalytic activity. On the other hand is due to the decrease of the grain size of Cu2O, increase its ratio surface area and reduce the light carrier migration distance, improve the cuprous oxide photocatalytic activity. A combination of both to further improve the photocatalytic activity of cuprous oxide, expand the cuprous oxide in application in the field of photocatalysis.