Redox-mediated bipolar hydrogen production and furoic acid electrosynthesis

Abstract

Hydrogen production coupled with electrosynthesis is one of the promising strategies for upgrading traditional water electrolysis with reduced energy consumption. However, this coupling concept always needs a separate time-consuming discharge process to restore the mediator, thus lowering the hydrogen productivity. Herein, we propose a novel three-chamber cell design to achieve continuous anodic and cathodic hydrogen production coupled with furfural electrooxidation. Zinc or organic redox-active molecule mediators were applied to effectively store and release energy and hydrogen independently on demand. Simultaneous hydrogen production from two different chambers enabled a furfural-hydrogen conversion efficiency of 184% with high energy-storage flexibility. The three-chamber cell enabled 2-furoic acid yield of above 95%, while simultaneous cycling yielded 2-furoic acid above 88% for 24 h. Our cell concept enhanced the time and energy efficiency of furfural-hydrogen co-production.