Synergistic activation of catalytic sites in NiFe−LDH architectures via coupling with nitrogen doped carbon/Mo2TiC2TX−MXene for high-efficiency alkaline oxygen evolution reaction

Green hydrogen production via electrocatalytic water splitting is often hindered by the sluggish kinetics of the oxygen evolution reaction (OER) at the anode. Therefore, developing highly efficient and cost-effective OER electrocatalysts is crucial in addressing the growing global energy demand. Among various candidates, NiFe–LDH (NF) nanostructures have shown great promise as OER electrocatalysts; however, their performance is significantly hindered by poor electronic conductivity and limited exposure of active catalytic sites. Herein, we present a novel OER electrocatalyst (NFMN), fabricated by anchoring NF nanostructures onto a hybrid support of Mo₂TiC₂T_X MXene (MX) and nitrogen-doped carbon (NC), which facilitates efficient electron transport. The resultant NFMN hybrid productively enhances the available surface area for catalytic interactions and improves the interface between the catalyst and the electrolyte. Notably, the strong synergistic electronic interactions among NF, MX, and NC in the NFMN catalyst result in outstanding OER performance, delivering a low overpotential of 259.7 mV at 100 mA cm⁻², along with decent stability over 100 h. Besides, a water-splitting device was constructed using NFMN as the anode and commercial Pt/C as the cathode, requiring a cell voltage of only 1.52 V to achieve 10 mA cm⁻² in alkaline solution. More impressively, it also demonstrated excellent durability, maintaining stable performance for over 50 h. Density functional theory (DFT) calculations further unveil that the incorporation of MX and NC significantly enhances the OER activity by strengthening interactions with OER intermediates. Moreover, the charge transfer occurs across the interface in NF@MX and NF@NC hybrids, highlighting strong interfacial interactions. This work offers a new pathway for designing and engineering advanced hybrid materials for next-generation renewable energy applications.