Strategies for the synthesis of complex oxides for application as light-responsive electrodes in photoelectrochemical cells – a review

Abstract

Complex oxides have emerged as potential next-generation components for photoelectrodes in reactors for solar energy conversion, due to their improved sunlight harvesting and enhanced stability in comparison to well-known semiconductors based on binary oxides. However, the experimental performances achieved with these emergent materials are still far from the theoretical values. The properties of these complex oxides largely depend on structure, particle-size, morphology and other tuneable characteristics that can be controlled by the synthesis methodology. The aim of this review is to discuss recent progress in synthesizing multinary complex oxides, presenting some common and also less conventional synthesis approaches, which are organized here into “dry” or “wet” methods. Then, we hope to contribute to the development of n and p-type semiconductors for photoelectrochemical generation of fuels like H₂ from water splitting and C-based products from CO₂ reduction or biomass valorisation, as well as, other reactions in the field of sustainable energy.