Mn–CoP/NC bifunctional catalysts with nanocube structures for alkaline water decomposition

Abstract

Developing highly efficient non-precious metal bifunctional catalysts remains a critical challenge in electrolytic water splitting research. In this study, we prepared Mn-doped CoP coupled with nitrogen-doped carbon nanocube (Mn–CoP/NC) catalysts using an in situ growth, low temperature oxidation, and phosphatization strategy. Due to the excellent activity of the cobalt species and the effective protection provided by the carbon shell to the metal core, these Mn–CoP/NC catalysts exhibited outstanding hydrogen evolution reaction (HER) and oxygen evolution reaction (OER) performances. At a current density of 10 mA cm², the overpotentials were as low as 90 mV for the HER and 272 mV for the OER. Moreover, the Mn–CoP/NC‖Mn–CoP/NC cell achieved a current density of 10 mA cm⁻² at just 1.66 V and remained highly stable after 36 hours of continuous operation. This study offers a new strategy for designing efficient bifunctional catalysts for overall water splitting.