Electron configuration modulation of rare earth metal for remarkably elevated hydrogen evolution reaction

The heterogeneous-element doping engineering has been emerged as an intriguing strategy to precisely modulate the local electronic structure of transition metal phosphides (TMPs) for hydrogen evolution reactions (HER), which remains a grand challenge. Herein, a novel and universal strategy is achieved via incorporating rare earth (RE) metals (RE = Gd, Tb, and Ho) into FeNi-based phosphides embedded in nitrogen-doped carbon nanotubes ([email protected]). Three catalysts prepared exhibit various extrinsic morphologies, good hydrophilic features, and outstanding intrinsic catalytic activity. [email protected], [email protected], and [email protected] afford a high HER activity with the low overpotential of 63.3, 47.5, and 99.8 mV at 10 mA cm−2 (η10) in the acidic electrolyte, respectively. In particular, [email protected] exhibits superior durability for 95 h at 150 mA cm−2 with nearly negligible decay. The state-of-art structural characterizations and density functional theory (DFT) calculations demonstrate that RE metals doping can precisely regulate the Gibbs free energy of hydrogen adsorption (ΔGH*) of [email protected] by electron configuration modulation and FeP/RE oxide (REO) heterojunction. This strategy initially unravels an effective template based on the RE-controlled synthesis of FeNi-based phosphides to construct highly-active and stable HER electrocatalysts, paving a new avenue for engineering and commodifying of the RE doped TMPs in the fields of energy storage and conversion.