Enhanced photocatalytic performance of Ce-doped SnO2 hollow spheres by a one-pot hydrothermal method

The pure and Ce-doped (3 wt%, 5 wt%, 7 wt%) SnO2 hollow spheres have been successfully prepared by a simple one-pot hydrothermal method. The microstructures and optical properties of as-prepared samples were characterized by different techniques, such as XRD, EDS, XPS, SEM, TEM, BET, FTIR and UV-vis DRS. The results showed that Ce ions were doped into the SnO2 lattice, and the diameter of the Ce-doped SnO2 hollow sphere was about 200-350 nm. The photocatalytic results showed that all Ce-doped SnO2 hollow spheres samples exhibited higher photocatalytic performance than pure SnO2 in the degradation of malachite green (MG) under UV light. The 3 wt% Ce-doped SnO2 hollow spheres photocatalyst has the highest photocatalytic activity, and the degradation efficiency of MG reaches 92% after UV light irradiation 120 min. However, the degradation efficiency of pure SnO2 is only 63%. The enhanced photocatalytic activity of Ce-doped SnO2 can be attributed to the formed defects caused by Ce doped can further inhibit the electron-hole recombination. In addition, the hollow structure of Ce-doped SnO2 also enable reactant molecules to reach the reactive site more efficiently. A plausible photocatalytic mechanism was proposed for the degradation of MG under UV light irradiation.