Towards Efficient and Acidically Stable Dye-Sensitized Photocathodes for Solar Fuels

Photocatalytic water splitting is an attractive approach for converting intermittent solar energy into clean fuels. Tandem dye-sensitized photoelectrichemical cells mimic the Z-scheme in photosynthesis by integrating a dye-sensitized photoanode (DSPA) with a dye-sensitized photocathode (DSPC). However, the tandem design is limited by two main factors: efficiency mismatch between DSPA and DSPC, and electrode instability under long-term operation. In this talk, I will talk about our recent progress in the design of dye and molecular catalysts towards efficient and acidically stable DSPC for photocatalytic water reduction into hydrogen. With our newly developed molecules, we have demonstrated an increase of photocurrent by ~2 orders of magnitude and stable operation in aqueous solutions with pH down to zero.