三维Ag2O/WO3复合催化剂的制备及光催化性能研究

WO3是一种带隙约为2.7 eV的过渡金属半导体,可见光就能激发其光催化活性,这极大地提高了太阳光的利用率,但纯WO3纳米材料催化活性偏低,针对这一难题,本文选取了三维网格结构的WO3纳米材料为载体,利用化学搅拌法制备了不同摩尔比的Ag2O/WO3复合光催化剂.选择亚甲基蓝为研究对象,测定了不同摩尔比的Ag2O/WO3复合催化剂的光催化性能.实验表明,当Ag2O和WO3的摩尔配比为1∶2时,该复合催化剂的光催性能最好.过量的Ag2O纳米颗粒会增加Ag2O/WO3内部电子空穴的复合几率,反而导致光催化剂反应活性的降低.

Synthesis of Three-dimensional Ag2O/WO3 and Investigation of Its Photocatalytic Activity

Due to WO3 with the band bap of about 2.7 eV, visible light can be used to stimulate the photocatalytic activity, which greatly improve the utilization rate of sunlight.However, the photocatalytic activity of pure WO3 nanopowder is relatively low.In order to solve this problem, WO3 nanonetworks were used as the 3D frame for loading Ag2O nanoparticles.Ag2O/WO3 heterostructures composite were prepared with different molar ratio of WO3 to Ag2O via a simple chemical precipitatation method.To explore the photocatalysis of the heterostructures, the photodegradation of methylene blue was carried out under simulated sunlight irradiation.Photocatalytic activity was enhanced by loading Ag2O nanoparticles on the WO3 networks and the optimum molar ratio of WO3 to Ag2O is 1∶2.Then the photocatalysis decreased with the excessive amount of Ag2O, which may be attributed to the recombination of electrons form WO3 and holes from Ag2O.