Designing idealised devices for bias-free solar water splitting

Abstract

The efficient conversion of solar energy into storable and distributable hydrogen is challenging, particularly in the development of cost-effective and efficient devices. As efficiency and cost are determined primarily by the materials and design of the devices, significant efforts have been devoted to discovering new materials and designing better device configurations. For designing ideal solar water splitting devices, a considerable key factor involves maximizing light absorption while minimising the travel distances of the electrical and ionic charge carriers. In this perspective article, unbiased photoelectrochemical (PEC) water-splitting device configurations reported in the literature were first classified into three categories: wired, wireless, and monolithic. Subsequently, we provide a brief overview and analysis, outlining the strengths and weaknesses of each configuration discussed. Through a systematic examination of PEC device configurations, this article sheds light on the path toward the ideal configuration for bias-free PEC water splitting devices, which holds great promise in advancing efficient conversion from solar energy to hydrogen.