Descriptor-Guided Design of Mo-Doped FeCoNiCu High-Entropy Alloy Electrocatalysts Surpassing Pt for Alkaline Hydrogen Evolution
Shiqi Wang, Haixian Yan, Wenyi Huo, Mahmoud Abdellatief, Feng Fang, Pedro H. C. Camargo
Abstract
High Resolution Image Download MS PowerPoint Slide High-entropy alloys (HEAs) offer an immense compositional playground for electrocatalyst discovery. Yet, the rational navigation of this space remains elusive. Here, we introduce a multidescriptor screening strategy combining density functional theory (DFT) calculations and data analytics based on critical parameters including d-band position, water dissociation energetics, hydrogen adsorption free energies, lattice stability, and corrosion resistance. This methodology systematically evaluates FeCoNiCu-based HEAs doped with transition metals (Ti, V, Cr, Zr, Nb, Mo, and W), identifying Mo as the optimal dopant due to its ideal balance between a low water dissociation barrier (0.41 eV) and near-thermoneutral hydrogen adsorption energies at Fe–Co–Ni hollow sites. Guided by computational predictions, phase-pure Mo-rich FeCoNiCu HEA films synthesized via magnetron sputtering deliver outstanding alkaline hydrogen evolution reaction (HER) activity, with an overpotential of just 60.1 mV at 10 mA cm –2, exceptional durability at −200 mA cm –2 over 100 h, and performance superior to commercial Pt/C catalysts. Soft X-ray absorption spectroscopy reveals dynamic Mo-mediated electron transfer among Fe, Co, and Ni, facilitating a dual-site Volmer–Heyrovsky mechanism. This study not only establishes an earth-abundant HEA that eclipses Pt for alkaline HER but also showcases a scalable “compute-screen-make-test” paradigm that can accelerate electrocatalyst discovery across the vast HEA design space.