Functionalization of the NiCoP electrocatalyst with phytic acid enables efficient and stable alkaline seawater hydrogen evolution reaction

Abstract

The development of highly efficient and stable electrocatalysts for the hydrogen evolution reaction (HER) is of critical importance to the industrialization of seawater electrolysis. In this study, we report the construction of phytic acid (inositol hexakisphosphate, IP₆) decorated nickel-cobalt phosphide nanoneedle arrays on nickel foam (IP₆@NiCoP/NF). Such an organic–inorganic hybrid structure not only optimizes the electronic structure of the catalyst and retains the high conductivity of TMPs but also exposes more active sites through the molecular regulation of IP₆. When operated in alkaline seawater, the IP₆@NiCoP/NF catalyst exhibits exceptional HER performance, capable of requiring a low overpotential of merely 268 mV to attain a high current density of 1000 mA cm⁻² while retaining stable operation for over 1600 hours. Theoretical calculations indicate that the IP₆ modification significantly accelerates the adsorption/dissociation process of seawater and reduces the value of ΔG_H* by the catalyst.