Tuneable Functionalization of Glass Fibre Membranes with ZnO/SnO2 Heterostructures for Photocatalytic Water Treatment: Effect of SnO2 Coverage Rate on the Photocatalytic Degradation of Organics

The construction of a ZnO/SnO(2)heterostructure is considered in the literature as an efficient strategy to improve photocatalytic properties of ZnO due to an electron/hole delocalisation process. This study is dedicated to an investigation of the photocatalytic performance of ZnO/SnO(2)heterostructures directly synthesized in macroporous glass fibres membranes. Hydrothermal ZnO nanorods have been functionalized with SnO(2)using an atomic layer deposition (ALD) process. The coverage rate of SnO(2)on ZnO nanorods was precisely tailored by controlling the number of ALD cycles. We highlight here the tight control of the photocatalytic properties of the ZnO/SnO(2)structure according to the coverage rate of SnO(2)on the ZnO nanorods. We show that the highest degradation of methylene blue is obtained when a 40% coverage rate of SnO(2)is reached. Interestingly, we also demonstrate that a higher coverage rate leads to a full passivation of the photocatalyst. In addition, we highlight that 40% coverage rate of SnO(2)onto ZnO is sufficient for getting a protective layer, leading to a more stable photocatalyst in reuse.