NiCo-Phosphide Bifunctional Electrocatalyst Realizes Electrolysis of Sugar Solution to Formic Acid and Hydrogen.

Abstract

As a promising liquid hydrogen carrier, formic acid is essential for hydrogen energy. Glucose, as the most widely distributed monosaccharide in nature, is valuable for co-electrolysis with water to produce formic acid and hydrogen, though achieving high formate yield and current density remains challenging. Herein, a nanostructured NiCoP on a 3D Ni foam catalyst enables efficient electrooxidation of glucose to formate, achieving an 85% yield and 200 mA current density at 1.47 V vs RHE. The catalyst forms a NiCoOOH/NiCoP/Ni foam sandwich structure via anodic oxidative reconstruction, with NiCoOOH as the active site and NiCoP facilitating electron conduction. Additionally, NiCoP/Ni foam serves as both an anode and cathode for the production of formate and hydrogen from wood-extracted sugar solutions. At 2.1 V, it reaches a 300 mA current density, converting mixed sugars to formate with a 74% yield and producing hydrogen at 104 mL cm2 h-1 with near 100% Faradaic efficiency.