Melamine – Ni-MIL-88A blend derived Trevorite/C-g-C3N4 for stable and efficient overall electrocatalytic water splitting applications

Abstract

The electrocatalytic splitting of water into hydrogen and oxygen plays a pivotal role in addressing the energy demands associated with expanding anthropogenic activities. The design of economically feasible and effective electrocatalytic materials for water electrolysis is imperative for the sustainable production of hydrogen and oxygen. In this context, this study introduces an electrocatalyst design comprising graphitic carbon nitride (g-C<inf>3</inf>N<inf>4</inf>) and Trevorite (Ni(Ni, Fe)<inf>2</inf>O<inf>4</inf>) synthesized through the pyrolysis of a mixture Ni-substituted metal–organic framework (MOF) MIL-88A and of melamine. The synthesized material was evaluated as an electrocatalyst for both the oxygen evolution reaction (OER) and the hydrogen evolution reaction (HER). The nickel foam coated with this electrocatalyst exhibits a performance characterized by lower overpotentials of 121 mV for HER and 231 mV for OER at a current density of 10 mA cm-2 in an alkaline medium of 1 M KOH. Furthermore, the composite demonstrated an excellent overall water splitting capacity, maintaining a high current density of 500 mA cm-2 for more than 50 h of continuous electrolysis in 1 M KOH solution with a minimal voltage increase of approximately 0.025 V. © 2025