The construction of photonic crystal/Cu2+ doped TiO2-SiO2 multilayer structured film for enhanced visible light photocatalytic performance: The synergistic effect between the different layers

For photocatalytic films, the low degradation efficiency has become an urgent problem to be solved due to the less amount of photocatalytic component. Therefore, it is particularly important to control the matching of interaction effect between each layer by adjusting the photonic crystal and doping, so as to achieve the best photocatalytic performance. Herein, Cu2+ doped TiO2-SiO2 (CTS) layer was deposited on SiO2 photonic crystal layer to construct multilayer structured films via vertical deposition method and calcination process. The photonic crystal/Cu2+ doped TiO2-SiO2 (PC/CTS) film shows the best photocatalytic performance although the amount of catalytic material is little, that is, the degradation rate of RhB by PC/CTS can reach 48.21% after 180 min of visible light irradiation, which is nearly 5 times than that of single-layer CTS film (10.97% after 180 min). Furthermore, a layer of amorphous SiO2 was deposited between SiO2 photonic crystal film and photocatalyst CTS layer to investigate the optical local interaction range of SiO2 photonic crystal. Finally, the mechanism of multilayer structured PC/CTS composite film is discussed, indicating that the synergistic effect between different layers is a decisive factor for effectively improving the visible photocatalytic performance of thin films. (c) 2022 Published by Elsevier B.V.