Cu/S-TiO2光催化剂的制备及其可见光催化性能(英文)

Preparation of Cu/S-TiO_2 Photocatalysts and their Catalytic Activities under Visible Light

分别采用化学镀铜法、化学还原法、浸渍法制备了3种Cu负载的S-TiO2光催化剂,综合利用UV-Vis、XRD、XPS、EXAFS、SEM和FESEM技术对制备的Cu/S-TiO2光催化材料的结构和光电子性能进行了表征.结果表明,化学镀铜法和浸渍法负载的铜物种为Cu2O和CuO,化学还原法制备的铜为Cu和Cu2O.化学镀铜法制备的Cu/S-TiO2光催化剂不仅对可见光具有很强的吸收能力,而且负载的铜物种连续、均匀地分散在S-TiO2表面,这种结构有利于光生电子的捕获、转移和分离.因此,化学镀铜法制备的Cu/S-TiO2在不同可见光波段(λ>420 nm,λ>500 nm)条件下光催化重整甲醇水溶液制氢反应中都表现出最高的催化活性,同时在模拟太阳光条件下以及稳定性实验的测试中也表现出优秀的性质,因此对其催化作用/反应机理进行了探讨.

Cu was loaded on the S-doped TiO2 by methods of electroless plating,wet impregnation and chemical reduction,respectively.The physical structure and chemical properties of the prepared Cu/S-TiO2 were characterized by UV-Vis,XRD,XPS,EXAFS and FESEM techniques.It was illustrated that copper species loaded by electroless copper plating and wet impregnation method were Cu2O/CuO,while Cu/Cu2O was loaded by chemical reduction method.The Cu/S-TiO2 prepared by electroless plating method showed excellent visible light absorption ability.The photocatalytic activities under visible light was investigated using various filtered wavelengths of light（λ 420 nm,λ 500 nm） for a period of 20 h.Moreover,the electroless plated copper on S-TiO2 were highly dispersed,which could facilitate the photo-generated charges capture,transfer and separation.Thus,the catalyst exhibited the highest photocatalytic activity and stability for hydrogen generation in methanol solution under simulated sunlight（Xe lamp）,and a possible catalytic effect/reaction mechanism was proposed.