TiO2-石墨烯（Gn）复合材料光催化降解O3研究

通过改性Hummer法及溶胶凝胶法,制备出TiO2-石墨烯光催化复合材料.经吸附-光催化活性实验选出光催化活性最高的含C量为1.5%(质量分数)的TiO2-石墨烯复合材料,并在自行设计的模拟大型客机环境的气相光催化反应器中,进行O3光催化降解实验研究.结果表明,TiO2-石墨烯复合光催化材料在较短时间内对O3有较高的降解效率,且其光催化活性显著优于纯TiO2材料.初始O3浓度为(0.150～0.200)×10-6时,复合光催化剂受紫外光激发60 min的光催化降解率为66.12%,初始O3浓度为(0.950～1.000)×10-6时,其光催化降解率约为77%,较低浓度时((0.100～0.150)×10-6),O3去除率也能达到45.45%.此外,通过探讨光催化材料的重复使用性能,表明复合光催化剂重复使用4次以内,其对O3的光催化降解率保持基本稳定.

Preparation of TiO2/graphene composites materials for photocatalytic degradation of O3

The TiO₂-graphene composite photocatalytic were synthesized by modified Hummers' method and the sol-gel method. The highest photocatalytic activity of TiO₂-graphene was selected by adsorption-photocatalytic activity experiments, and confirmed that the 1.5wt% of C content is the material. The O₃ photocatalytic degradation experiments were conducted in the self-designed gas-phase photocatalytic reactor, which was modeled on the large passenger aircraft. Experimental results showed that O₃ can be more efficiently removed by TiO₂-graphene composite photocatalyst materials and its photocatalytic degradation activity was significantly higher than pure TiO₂ material. The initial O₃ concentration was (0.150~0.200)×10^-6, the composite photocatalyst was excited under UV for 60 min and the photocatalytic degradation rate could be 66.12%. Besides, the degradation rate would rise to about 77%, when the initial O₃ concentration was (0.950~1.000)×10^-6. While under the lower concentrations ((0.100~0.150)×10^-6), the O₃ removal rate dropped to 45.45%. In addition, the photocatalytic materials could be stable to photocatalytic degradation of O₃, if the composite was reused less than 4 times.