Fabrication of Flower-Like WO<sub>3</sub>/TiO<sub>2</sub> Core–Shell Nanoplates by Atomic Layer Deposition for Improved Photoelectrochemical Water-Splitting Activity
Kuang-I Liu, Tsong‐Pyng Perng
Abstract
Core–shell structured WO3/TiO2 nanoplates were prepared by a hydrothermal method and atomic layer deposition (ALD) technique. A spherical flower-like structure consisting of numerous nanoplates of WO3 using ammonium metatungstate as the precursor in the presence of nitric acid solution was obtained from the hydrothermal reaction. A TiO2 layer was then deposited on WO3 nanoplates by different cycles of ALD. The activities of the core–shell composites in photoelectrochemical water splitting were measured under the illumination of visible light and AM 1.5 solar light. They exhibited much improved photocatalytic activities compared with pure WO3 because the hybrid semiconductors could absorb more light and suppress the recombination rate of electron–hole pairs.