Photoelectrochemical Solar Fuels: What’sNext?

Abstract

The seminal demonstration of photoelectrochemicalwater splitting in the 1970s by Fujishima and Honda1using TiO2 sparked an enticing vision of inexpensiveand global scale artificial photosynthesis providing green fuelsfor transportation and sustainable chemical feedstocks forindustry. Over the decades since, it is unquestionable thatsignificant advances have been made in materials discovery andphotoelectrochemical device engineering. I have had thepleasure of being part of the research field during its surgeover the last 15 years, and while the promise of cheap andgreen H2 from solar-driven water splitting has undoubtedlycontinued to propel innovation and sustain momentum in thefield, as fueled by government-sponsored research support andventure-backed development, it is clear that we are still faraway from realizing the potential of solar fuels on an industrialscale. Moreover, from my point of view, the future ofphotoelectrochemical (PEC) solar fuel production researchstands at a crossroads