Utilizing solar energy to improve the oxygen evolution reaction kinetics in zinc-air battery.

ABSTRACT: Directly harvesting solar energy for battery charging represents an ultimate solution toward low-cost, green, efficient and sustainable electrochemical energy storage. Here, we design a sunlight promotion strategy into rechargeable zinc-air battery with significantly reduced charging potential below the theoretical cell voltage of zinc-air batteries. The sunlight-promoted zinc-air battery using BiVO₄ or ?-Fe₂O₃ air photoelectrode achieves a record-low charge potential of ~1.20 and ~1.43?V, respectively, under illumination, which is lowered by ~0.5-0.8?V compared to the typical charge voltage of ~2?V in conventional zinc-air battery. The band structure and photoelectrochemical stability of photoelectrodes are found to be key factors determining the charging performance of sunlight-promoted zinc-air batteries. The introduction of photoelectrode as an air electrode opens a facile way for developing integrated single-unit zinc-air batteries that can efficiently use solar energy to overcome the high charging overpotential of conventional zinc-air batteries.

SUBMITTER: Liu X 

PROVIDER: S-EPMC6800449 | biostudies-literature | 2019 Oct

REPOSITORIES: biostudies-literature