Bifunctional nickel phosphide nanoparticle/nickel cobalt sulfide nanosheet framework for electrocatalytic simultaneous hydrogen evolution and 2,5-Furandicaroxylic acid production

Replacing the O₂ evolution reaction of water splitting with a thermodynamically more favorable reaction has attracted considerable attention for simultaneous value-added feedstock formation coupled with H₂ production. Herein, bifunctional nickel phosphide nanoparticle/nickel cobalt sulfide nanosheet framework (NCSP150) is constructed on Ni foam for electrocatalytic hydrogen evolution reaction (HER) and 5-hydroxymethyl furfural (HMF) oxidation reaction (HMFOR) to 2,5-furandicaroxylic acid (FDCA) in 0.1 M KOH where HMF degradation is negligible. NCSP150 respectively demonstrates a Faradaic efficiency of 98.5 % for H₂ generation at 10 mA cm⁻² in 0.1 M KOH aqueous solution and exhibits a Faradaic efficiency of 95.2 % for FDCA formation at 1.52 V vs. RHE in a 10 mM HMF/0.1 M KOH aqueous solution. Moreover, NCSP150 sustains superior electrocatalytic performances for at least 12 h in the 0.1 M KOH electrolyte. In a two-electrode H cell using NCSP150 as both cathode and anode, the cell voltage required to afford the current density of 10 mA cm⁻² is less 153 mV than water electrolysis when adding 5 mM HMF in 0.1 M KOH. This work emphasizes bifunctional NCSP150 as a promising non-precious-metal electrocatalyst for simultaneous hydrogen evolution and FDCA production in 0.1 M KOH, suitable for scaling up industrial production.