石墨烯修饰的TiO_2光催化剂性能研究

Photocatalytic Performance of Graphene Modified TiO_2

石墨烯修饰的二氧化钛复合光催化剂已经引起科学界的广泛关注,如何提高其光催化性能更是成为一个研究热点。为了充分发挥石墨烯的作用,提高光催化剂性能,本研究同时采用氧化还原法制备的石墨烯纳米片和化学气相沉积法制备的三维网状石墨烯对二氧化钛进行改性。通过优化石墨烯纳米片表面官能团含量以及2种石墨烯的含量,提升复合光催化剂的活性。在紫外光照射条件下,其分解甲基橙的速率常数达到1.3×10^(-2) min^(-1)。采用红外光谱,X射线光电子能谱和电子顺磁共振谱等手段对样品进行表征,证明石墨烯和二氧化钛之间存在协同作用。另外,该复合光催化剂具有良好的稳定性和长使用寿命。

Graphene modified TiO_2 composite photocatalysts have drawn increasing attention,and how to improve the resulting photocatalytic performance becomes a hot issue.In order to achieve the full potential of the modifier,the reduced graphene oxide（RGO）and three-dimensional graphene network（3DGN,prepared by chemical vapor deposition method）are adopted to modify TiO_2.After optimizing the residual amount of surface functional group of the RGO and mass fractions of the RGO and 3DGN,the decomposition rate constant of methyl orange reaches 1.3×10^（-2） min^（-1） under UV-light irradiation.A synergy between the graphene and TiO_2 is proved by using IR,XPS and EPR spectra.Moreover,the composite photocatalyst displays a well stability and long lifetime.