N-integration in Ni-Fe-Cr-Ru-Mo High-Entropy Electrocatalytic Materials

Multi-principal element materials (MPEMs) also known as high entropy materials (HEMs) are regarded as essential electrocatalytic materials for high-performance electrochemical applications including hydrogen electrolysers.1,2 MPEMs consisting of transition metal-based materials gained significant attention for their desired catalytic performance during oxygen evolution reaction (OER) and hydrogen evolution reaction (HER).3,4 However, their long-term durability especially in acidic environments are yet to be improved and requires further investigation.5 One of the latest approaches to improve the catalytic properties of MPEM is to incorporate small elements such as nitrogen (N) into the microstructure at different concentrations, aiming to induce defects and N to metal bonds to tune the surface energy or to form secondary phases with high catalytic activity. The influence of this method on catalytic activity and durability of MPEMs needs to be studied.6