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以P25为原料,采用碱热法制备二氧化钛纳米管(TiO2 nanotubes,TNT),Hummers法制备氧化石墨(Graphite Oxide,GO),水热法生成石墨烯二氧化钛纳米管(GR/TNT)复合光催化剂.通过XRD、FTIR、SEM及UV-Vis光谱仪对材料进行表征,表明GR/TNT由化学键结合,且禁带宽度由3.2 eV减小到1.38 eV.掺杂GR可抑制TNT空穴和电子间的复合,且拓宽其光响应范围,光催化活性可延伸到可见光范围.通过GR/TNT降解苯酚,确定其最佳制备条件.180℃下水热反应3h的2.5％ GR/TNT光催化效果最佳,在紫外光(11 W)和可见光(500 W)条件下,10 mg/L的苯酚降解率分别可达95％和80％.GR/TNT降解苯酚满足一级反应动力学方程(R2≥0.95),且具有较好的稳定性和重复使用性,循环5次利用率可达到初次的88％.“,”Titanium dioxide nanotubes (TNT) were prepared using P25 as titanium source by the concentrated alkaline hydrothermal method,and graphite oxide (GO) was prepared by Hummers Method,and then graphene-TiO2 nanotube (GR/TNT) composite photocatalysts were prepared by the hydrothermal method.The properties of GR/TNT composite photocatalysts were characterized by XRD,FTIR,SEM,and UV-Vis spectroscopy,showing that GR/TNT were closely linked by chemical bonds and the band gap of GR/TNT was reduced from 3.2 eV to 1.38 eV.Doping GR could inhibit the recombination of TNT holes and electrons as well as broaden the range of light response of TNT400,which resulted in the photocatalytic activity extending to the visible range.The optimum conditions were determined by degrading the phenol.Photocatalytic effect of GR/TNT with the GR content of 2.5％ was the best at 180 ℃ for 3 h,the degradation rate of phenol solution with the concentration of 10 mg/L were 95％ and 80％ after 3 h under UV-light (UV lamp 11 W) and visible light (Xe lamp 500 W) irradiation respectively.Degradation of phenol by GR/TNT followed the first order reaction kinetics (R2 ≥ 0.95).The GR/TNT composite photocatalytic had good stability and repeatability for degradation rate of phenol,whose utilization could still reach 88％ after 5 cycles.