Title : Improving the photoelectrochemical stability and performance of BiVO4 photoanode using In2Se3 as a protective layer in a harsh environment
Abstract:
Hydrogen production from water splitting using photoelectrochemical (PEC) technology has become an important alternative to sustainable and green energy sources. However, getting photoelectrodes with long-term stability, particularly in harsh environments, requires unwavering effort. Herein, we have introduced a conformal surface engineering of the photoelectrode using In2Se3, a novel two-dimensional (2D) protective layer to secure the performance and stability of BiVO4 at elevated pH electrolytes. The method involves In2Se3 self-assembling between immiscible solvents, then transferring onto BiVO4 electrode, resulting in a uniform coating. BiVO4 after In2Se3 coating shows a superior stability at higher pH (12 and 13) than pure BiVO4, at a potential 0.6 V vs RHE under 100 mW cm−2 of simulated air mass 1.5 illumination. The elemental and morphology analysis after stability tests proves the role of In2Se3 for effective suppression of vanadium ion dissolution. Moreover, the incident photon-to-current conversion efficiency and absorption spectra suggests that In2Se3 contributes to improve the photocurrent of BiVO4 by photon absorption and charge separation. These results suggested that In2Se3 and other novel 2D materials shows a promising as a protection layer for photoelectrodes that working for long term stability during PEC operations.
