The two-step anodization combined with hydrothermal techniques was applied to synthesize heterojunction TiO2/SrTiO3 nanotube arrays under different hydrothermal reaction time. X-ray diffraction (XRD), field emission scanning electron microscopy (FE-SEM) and field emission transmission electron microscopy (FE-TEM) were used to characterize crystal structures and morphologies of TiO2/SrTiO3 heterojunctions. The photoelectrochemical properties of heterojunction materials were evaluated by open-circuit potential spectrum and transient photocurrent spectrum. Meanwhile, photoelectrocatalytic activities and photocorrosion resistant properties of TiO2/SrTiO3 heterojunction were investigated by measuring the degradation rate of Rhodamine B (Rh.B) under ultraviolet light. The experimental re-sults show that TiO2 in situ formed SrTiO3 nanocrystals on the surface of nanotube arrays and the preferred orientation growth of (004) crystal facet was boosted by the formation of SrTiO3 nanocrystals. TiO2/SrTiO3 heterojunctions with 1,h to 5,h hydrothermal time still exhibited good photoelectrocatalytic activity.Photoelectric performance test found that the heterojunction TiO2/SrTiO3 under 2,h hydrothermal treatment (STNs-2) exhibited the best photoelectrochemi-cal properties. Furthermore, the photoelectric degradation test revealed that the efficiency of deposing a Rh.B solution was 1.71 times than that of pure TiO2 under 200 s photoelectrocatalytic reaction and showed better photocorrosion resistant property.%通过两步阳极氧化法结合水热法,制备不同水热反应时间条件下的异质结TiO2/SrTiO3纳米管阵列,利用X射线衍射(XRD)、场发射扫描电子显微镜(FE-SEM)、场发射投射电镜(FE-TEM)表征手段对异质结TiO2/SrTiO3材料进行表征,并通过开路电压谱和瞬态光电流图谱分析对异质结光催化材料的光电化学特性进行了研究,同时紫外光下降解罗丹明B(Rh.B)来研究异质结TiO2/SrTiO3材料的光电催化活性和耐光腐蚀稳定性.实验研究表明,TiO2表面发生原位取代形成SrTiO3晶体颗粒,并促使TiO2锐钛矿(004)晶面的趋向生长.水热1~5,h的异质结TiO2/SrTiO3纳米管阵列仍具有较好的催化活性.通过光电性能测试,水热反应2,h后的异质结材料表现出最好的光电化学特性.此外,光电催化结果表明,光电催化200,s、水热反应2,h的异质结材料的降解率是纯TiO2纳米管的1.71倍,且表现出较好的耐光腐蚀稳定性.
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