Porous g‐C ₃ N ₄ Nanosheets with Atomically Dispersed (Fe, Co)‐N _x ‐C Active Sites on Reduced Graphene Oxide for Efficient Electrocatalytic Hydrogen Evolution

Abstract Hydrogen, increasingly recognized as a sustainable energy carrier, necessitates the process of developing efficient and cost‐effective electrocatalysts to drive the hydrogen evolution reaction (HER). While precious metals have shown exceptional HER activity, their scarcity and high cost limit their widespread application. This study introduces an efficient bimetallic metal‐nitrogen‐carbon (M‐N x ‐C) active sites, comprising cobalt and iron atoms anchored on graphitic carbon nitride porous nanosheets (CNPN) supported by reduced graphene oxide (rGO). The developed catalysts are analyzed by sophisticated characterization methods, confirming the incorporation of distinctive (Fe/Co)‐N x ‐C active sites within the highly porous and active surface area formed by the CNPN network. In alkaline conditions, the optimized (Fe, Co)‐CNPN‐2@rGO catalyst shows HER activity at a low overpotential of only 146 mV at a current density of 10 mA cm −2 . This exceptional performance is attributed to the synergistic effect of the bimetallic active sites, high surface area, porosity, and rapid charge transfer kinetics. The (Fe, Co)‐CNPN‐2@rGO catalyst outperforms many previously reported non‐precious metal‐based catalysts in alkaline conditions and demonstrates excellent stability over extended periods. This study offers essential information in designing and optimizing the M‐N x ‐C active sites for efficient hydrogen production, which enables the development of affordable and sustainable energy technologies.