Chapter 9 - Dye-sensitized photoelectrochemical cells in water splitting

Abstract

Dye-sensitized photoelectrochemical cells (DSPECs) are gaining growing interest as a viable alternative for visible-light-driven water electrolysis for hydrogen (H2) generation. The generated H2 has the potential to meet the energy needs of modern civilization while having minimal impact on the environment. DSPECs are made up of wide-bandgap nanostructured metal-oxide semiconductors (MOSs) and chromophore-catalyst assemblies designed to push the two halves of the water splitting process into physically isolated compartments. The two primary reactions in water oxidation and proton reduction occur at the photoanode and cathode, respectively, and are referred to as the oxygen evolution reaction (OER) and the hydrogen evolution reaction (HER), respectively. DSPECs have shown outstanding efficiency in converting sunlight into hydrogen in recent years, but they have not been commercially feasible due to high production costs. The present study encompasses state-of-the-art DSPECs and various advancements in DSPECs' functional architecture to improve their water splitting efficiency and stability. We further highlight the current challenges and prospects for the widespread adoption of DSPEC technology.