In most cases, different morphologies of the same composites correspond to different properties. In this paper, the TiO₂/rGO heterostructure system with three morphologies was obtained by one-step hydrothermal method through regulating hydrothermal time. Compared with TiO₂ nanoparticle/reduced graphene oxide (TNP/rGO) and TiO₂ nanobelt/reduced graphene oxide (TNB/rGO), TiO₂ nanotube/reduced graphene oxide (TNT/rGO) showed higher photocatalytic activity (78.5%, 2 h) toward degrading Rhodamine B and 2, 4-Dichlorophenol under visible light. The mechanism of enhancing photocatalytic activities of the TiO₂/rGO system was confirmed by free radicals trapping experiment, ESR, PL and photocurrent measurement. It is revealed that the hole (h⁺) is the main reactive specie in TNT/rGO heterojunction and rapid transfer of photogenerated electrons is responsible for enhancing photocatalytic activity. This work not only emphasizes the important role of morphology in improving photocatalytic activity, but also provides a simple strategy to alter the morphology of TiO₂.

在大多数情况下，相同复合材料的不同形态对应于不同的特性。本文通过调节水热时间，通过一步水热法获得了三种形态的TiO ₂ / rGO异质结构体系。与TiO ₂纳米颗粒/氧化石墨烯（TNP / rGO）和TiO ₂纳米带/氧化石墨烯（TNB / rGO）相比，TiO ₂纳米管/氧化石墨烯（TNT / rGO）具有更高的光催化活性（78.5％，2 h）。 ），使其在可见光下降解若丹明B和2,4-二氯苯酚。增强TiO ₂光催化活性的机理自由基俘获实验，ESR，PL和光电流测量证实了/ rGO体系。结果表明，空穴（h ⁺）是TNT / rGO异质结中的主要反应物种，光生电子的快速转移有助于增强光催化活性。这项工作不仅强调了形态学在改善光催化活性中的重要作用，而且还提供了一种改变TiO ₂形态学的简单策略。