Photocatalytic H2 production of composite one-dimensional TiO2nanostructures of different morphological structures and crystal phases with graphene

Abstract

One-dimensional TiO₂ nanostructures of different structural phases with graphene composites were employed as photocatalysts for photocatalytic H₂ production. Two strategies have been explored for enhancement of photocatalytic reactivity. The first is demonstrated through the use of one-dimensional nanostructures, which feature good vectorial electron transport due to decreased grain boundaries. The second strategy is to form a composite/network with two-dimensional reduced graphene oxide (RGO), which features visible light photosensitization and is an efficient charge transporter and separator. It is noted that other than structural design, it is crucial to attain anatase phase structures and superior interfacial contact between GO and TiO₂ nanostructures to enable optimal synergy between one-dimensional TiO₂ nanostructures and graphene for enhanced photocatalytic H₂ production performance. In this work, hydrothermal synthesis and an in situ solution-based photoreduction method are used owing to their scalability, low temperature, high yield and ease of temperature and reactant concentration control characteristics.