One-pot synthesis of Cu2O/C@H-TiO2 nanocomposites with enhanced visible-light photocatalytic activity

Abstract

As an environment-friendly semiconductor, titanium dioxide (TiO2), which can effectively convert solar energy to chemical energy, is a crucial material in solar energy conversion research. However, it has several technical limitations for environment protection and energy industries, such as low photocatalytic efficiency and a narrow spectrum response. In this study, a unique mesoporous Cu2O/C@H-TiO2 nanocomposite is proposed to solve these issues. Polystyrene beads ((C8H8)(n), PS) are utilized as templates to prepare TiO2 hollow microspheres. Cu2O nanocomposites and amorphous carbon are deposited by a one-pot method on the surface of TiO2 hollow spheres. After the heterojunction is formed between the two semiconductor materials, the difference in energy levels can effectively separate the photogenerated e(-)-h(+) pairs, thereby greatly improving the photocatalytic efficiency. Furthermore, due to the visible band absorption of Cu2O, the absorption range of the prepared nanocomposites is expanded to the whole solar spectrum. Amorphous carbon, as a Cu2O reduction reaction concomitant product, can further improve the electron conduction characteristics between Cu2O and TiO2. The structure and chemical composition of the obtained nanocomposites are characterized by a series of techniques (such as SEM, EDS, TEM, XRD, FTIR, XPS, DRS, PL, MS etc.). The experimental results of the degradation of methylene blue (MB) aqueous solution demonstrate that the degradation efficiency of Cu2O/C@H-TiO2 nanocomposites is about 3 times as fast as that of pure TiO2 hollow microspheres, and a more absolute degradation can be achieved. Herein, a recyclable photocatalyst with high degradation efficiency and a whole solar spectrum response is proposed and fabricated, and would find useful applications in environment protection, and optoelectronic devices.