In-Situ Noble Fabrication of Bi2S3/BiVO4 Hybrid Nanostructure through a Photoelectrochemical Transformation Process for Solar Hydrogen Production

Here, we establish a methodology and phenomena for systematically assessing the photoelectrochemical transformation of the BiVO4 to Bi2S3/BiVO4 hybrid heterostructure during in-situ solar hydrogen generation. The photoelectrochemical transformation involves a facile anion exchange process by reacting BiVO4 photoelectrodes with Na2S/Na2SO3 electrolyte. X-ray photoelectron spectroscopy and transmission electron microscopy analyses confirmed the successful transformation of BiVO4 into the Bi2S3/BiVO4 nanostructure matrix. The photocurrent density of the ABV3 photoelectrode is optimized to be 3.3 mA cm–2 with hydrogen generation activity (∼417 μmol cm–2 h–1) under simulated sunlight at 0.67 V versus reversible hydrogen electrode (RHE). The impacts of other factors such as crystal structure, enhancing light harvesting, and increasing electron–hole separation on the photoelectrochemical performance and stability of Bi2S3/BiVO4 hybrid photoanodes are highlighted. A model based on the photoelectrochemical transfo...