GO复合的混晶TiO_2的光催化性能

Photocatalytic performance of GO/TiO_2 composite with mixed crystal structure

利用溶胶-凝胶法原位制备氧化石墨烯复合的TiO_2(简称GO/TiO_2),通过扫描电镜、X射线衍射、紫外-可见漫反射吸收光谱和亚甲基蓝的降解对制备过程中的影响因素进行了分析。结果表明,当m(氧化石墨烯)∶m(TiO_2)为1.05%、焙烧温度为450℃时,催化剂的活性最高,紫外光照4 h后,亚甲基蓝基本降解完全。GO的掺入降低了锐钛矿相向金红石相的转变温度。1.05%GO/TiO_2为混晶结构,主要以板钛-锐钛矿相存在,并含少量金红石相,平均晶粒约为9.8 nm,颗粒分布较为均匀。少量GO的复合明显增强了TiO_2的光响应性能。

Graphene oxide/titanium dioxide（ GO/TiO2） composite with mixed crystal structure is prepared in situ by the sol-gel method.The influence factors in the preparation process are investigated by means of SEM,XRD,UV-Vis absorption spectroscopy and the degradation of methylene blue. The results show that the GO/TiO2 composite has the highest catalytic activity when m（ GO） ∶ m（ TiO2） is 1. 05% and the calcination temperature is 450℃.With the presence of the prepared GO/TiO2 composite,methylene blue has completely degraded after it has been irradiated by ultraviolet for four hours.The transition temperature from anatase phase to rutile phase has been reduced because of incorporating GO.The 1. 05% GO/TiO2 has a mixed crystal structure,which is mainly existed in brookite-anatase phase,containing a small amount of rutile phase.The average size of crystal grain is about 9. 8 nm and the particle diameters distribute uniformly.The light response performance of TiO2 is obviously enhanced through compositing with a small amount of GO.