BiOBr/石墨烯/TiO2纳米管阵列薄膜的制备及光电化学性能研究

Preparation of BiOBr/graphene/TiO2 nanotube array film and its photoelectrochemical performance

通过水热处理TiO2纳米管阵列和氧化石墨烯制备石墨烯/TiO2纳米管薄膜材料,并进一步连续离子沉积BiOBr来制备BiOBr/石墨烯/TiO2纳米管阵列薄膜材料。利用X射线衍射仪、扫描电子显微镜、X射线电子能谱和紫外-可见漫反射光谱等测试手段对所得样品的物相组成、表面形貌及元素形态和光吸收性能等进行表征。结果表明,TiO2纳米管的表面成功负载了石墨烯和BiOBr纳米片。紫外-可见漫反射吸收光谱表明,BiOBr和石墨烯共同修饰的TiO2纳米管的吸收带边发生明显红移,其可见光吸收性能明显提高。光电电化学性能测试表明,BiOBr和石墨烯的共同修饰有效提高了TiO2纳米管的光电流、光电压和光电转换效率。

Graphene/TiO2 nanotube array film materials,prepared by hydrothermal treatment of TiO2 nanotube arrays and graphene oxide,are further decorated with Bi OBr via a successive ion deposition to construct Bi OBr/graphene/TiO2,a kind of ternary composite nanotube array film materials.The phase composition,surface morphology,chemical states of elements and optical adsorption property of the as-prepared samples are characterized by X-ray diffractometry( XRD),scanning electron microscopy( SEM),X-ray electron spectroscopy( XPS) and ultraviolet-visible diffuse reflectance spectroscopy( UV-Vis DRS). The results disclose that graphene and Bi OBr nanosheets are successfully loaded on the surface of TiO2 nanotube arrays. A red-shift of the absorption edge and enhanced light absorption intensity in the UV-Vis DRS are observed for the prepared Bi OBr/graphene/TiO2 nanotube arrays in comparison with TiO2 nanotube arrays and graphene/TiO2 nanotube arrays. Moreover,the photoelectrochemical and electrochemical detection results indicate the co-modification of Bi OBr and graphene improves the photocurrent,open circuit potential,and photo-conversion efficiency of TiO2 nanotube.