Green hydrogen production possible with semiconductor electrodes: Study

Finnish researchers from the University of Jyväskylä have demonstrated that semiconductor electrodes, specifically titanium dioxide (TiO2), can be used for green hydrogen production through (photo)electrochemical processes. Their study combined advanced atomic-level simulations with precise spectroelectrochemical experiments to uncover the fundamental mechanisms of the hydrogen evolution reaction on TiO2. Unlike traditional metal-based catalysts, semiconductor materials are composed of more abundant and less costly elements, but their electrochemical and catalytic behaviors have been poorly understood until now. The team developed a novel simulation approach called constant inner potential density functional theory, which incorporates electrode potential into modeling semiconductor electrochemistry. Their simulations revealed that applying a negative electrode potential induces the formation of local charge centers known as polarons on the TiO2 surface. These polarons facilitate hydrogen binding and activate the hydrogen evolution reaction. This polaron formation, experimentally confirmed through advanced techniques such as photoelectrochemical Raman spectroscopy and in situ electron resonance spectroscopy, is a previously unknown electro