RGO-PEI-TiO_2纳米线复合催化剂的制备及性能研究

Preparation and characterization of RGO-PEI-TiO_2 nanowire composite catalyst

采用改进的Hummers法制备氧化石墨,以硫酸钛为钛源采用水热法制备了还原氧化石墨烯(RGO)-聚乙烯亚胺(PEI)-二氧化钛(TiO_2)纳米线复合催化剂(RGO-PEI-TiO_2),通过扫描电子显微镜(SEM)、透射电镜(TEM)、X射线光电子能谱(XPS)、紫外-可见分光光度计(UV-Vis)对RGO-PEI-TiO_2的形貌,结构和光催化活性进行了表征。研究结果表明:在RGO-PEI-TiO_2复合催化剂中TiO_2纳米线负载在石墨烯的表面,大部分的TiO_2纳米线生长的直径大小比较均匀,具有很好的分散性;在紫外光激发,降解5h条件下,RGO-PEI-TiO_2对甲基橙的降解率达到100%,PEI的加入很好的降低了石墨烯的团聚,有助于电子的传递,提高了电子转移到TiO_2的速率,抑制了TiO_2半导体光生电子与空穴的复合,增强了RGO-PEI-TiO_2对甲基橙的降解功能。

The modified hummers method was used to prepare graphite oxide,and the reduced graphene oxide（RGO）-polyethyleneimine（PEI）-titanium dioxide（TiO2）nanowire composite catalyst（RGO-PEI-TiO2）was prepared by hydrothermal method using titanium sulfate as the titanium source.The morphology,structure and photocatalytic activity of RGO-PEI-TiO2 were characterized by SEM,TEM,XPS and UV-Vis.The results shewed that TiO2 nanowires were supported on the surface of graphene in RGO-PEI-TiO2 composite.Most of TiO2 nanowires grew in a uniform diameter and had good dispersion.Under ultraviolet excitation and degradation time was 5 h,the degradation rate of methyl orange by RGO-PEI-TiO2 was 100%.The addition of PEI can reduce the agglomeration of graphene,contributed to electron transfer,increased the rate of electron transfer to TiO2,and inhibited the rate.The recombination of photogenerated electrons and holes of TiO2 semiconductor enhanced the degradation of methyl orange.