Hybrid acid/alkali electrolysis toward industrial-scale H2 generation and sulfite oxidation conversion

Abstract

Co2P has been widely applied in a variety of applications yet still faces challenges in implementing hypotoxic and large-scale synthesis. We here report a scalable synthetic route to produce tussock-like nanostructured Co2P (t-Nano Co2P), which exhibits high-performance electrocatalytic properties toward acidic hydrogen evolution reaction (HER). Such t-Nano Co2P can evolve to CoOOH nanoplates that show excellent electrocatalytic activity for sulfite oxidation reaction (SOR) in alkaline solution. The findings encourage us to construct a hybrid acid/alkali electrolyzer with t-Nano Co2P and its CoOOH derivative as catalysts of acidic cathode for HER and alkaline anode for SOR, respectively, which performs excellently with capability of synchronous generation of H2 and sulfate in an industrial-level rate at a relatively low applied voltage. The proof-of-concept electrolyzer, by virtue of the viability of scalable synthesis and high-production yield, holds great promise for co-production of H2 and sulfate in an energy-effective and environmentally-friendly manner.