Interfacial coupling and dopant-induced electronic modulation enabling Mn–CoP/MXene heterostructures to reduce alkaline HER energy barriers

Electronic structure modulation is a promising strategy to reduce energy barriers of hydrogen evolution reaction (HER). We have constructed 3D monodispersed Mn doped CoP nanoflowers supported on MXene sheets (Mn–CoP/MXene) to boost the alkaline HER kinetics, and the enhanced mechanisms were clarified by photoelectron spectroscopies tests and density functional calculations. The Mn doping and MXene coupling resulted in the modulated electronic structure and, thus, improved active sites for balancing the free energy of H2O dissociation and *H intermediates. The HER activity has been strengthened by the synergy of Mn doping and MXene coupling with an overpotential of only 95 mV to 10 mA cm−2, a ultra-small Tafel slope of 54.1 mV dec−1, and outstanding stability in 1.0 M KOH electrolyte. This work highlights the potential of the synthetic strategy of heteroatom doping and 2D materials coupling to be extended to prepare advanced and cost-effective TMPs-based electrocatalysts.