Facet Engineering on WO<sub>3</sub> Mono‐Particle‐Layer Electrode for Photoelectrochemical Water Splitting
Wenrui Lin, Boyang Zhang, Kaiwei Liu, Jifang Zhang, Jiaming Wang, Guijun Ma
Abstract
Abstract Photoelectrochemical (PEC) performance of WO 3 photoanodes for water splitting is heavily influenced by the orientation of crystal facets. In this work, mono‐particle‐layer electrodes, assembled by particulate WO 3 square plates with highly uniform alignment along the (002) facet, improved PEC water oxidation kinetics and stability. Photo‐deposition of Au along the cracks formed on the surface of the plates, which are the edges of {110} facets, was found to further enhance electron collection efficiency. Combination of these two strategies allowed the facet‐engineered WO 3 electrode to produce significantly higher efficiencies in charge separation and transfer than the electrode prepared without facet orientation. This work has provided a facile route for fabricating a structurally designed WO 3 photoelectrode, which is also applicable to other regularly shaped semiconductor photocatalysts with anisotropic charge migration.