Bifunctional integrated electrode for high-efficient hydrogen production coupled with 5-hydroxymethylfurfural oxidation

The sluggish oxygen evolution reaction (OER) limits the efficiency of overall water splitting, which thereby hinders hydrogen evolution reaction (HER). Here, we demonstrate a bifunctional CoNiP nanosheet integrated electrode (CoNiP-NIE) to boost HER and replace OER by 5-hydroxymethylfurfural oxidation reaction (HMFOR) to obtain high-valued 2,5-furandicarboxylic acid (FDCA). The as-developed CoNiP-NIE exhibits a constant high Faradaic efficiency more than 82% for HMFOR in a wide potential from 1.40 V to 1.70 V vs. RHE, which stand at the top level among the reported electrocatalysts. Moreover, the low overpotential for HER further indicates its high efficiency in the H2 generation. Based on the bifunctional activity of CoNiP, an electrochemical hydrogen evolution coupled with biomass oxidation device is constructed, which delivers lower voltage (1.46 V) for anode oxidation and higher evolution rate of H2 (41.2 L h−1 m−2) than water splitting (1.76 V, 16.1 L h−1 m−2). We report a bifunctional CoNiP nanosheet integrated electrode by facile ion etching and subsequent phosphidation process, which shows promising activity for HMFOR and HER simultaneously. This work thus could provide a successful paradigm for rational design bifunctional electrocatalysts for highly efficient hydrogen production coupled with biomass oxidation. [Display omitted] •The CoNiP-NIE exhibits high FEFDCA in a wide potential from 1.40 to 1.70 V vs. RHE.•An EHCO device based on bifunctional CoNiP-NIE enhances the evolution rate of H2.•CoNiP displays moderate desorption for FDCA and enhanced electrical conductivity.