Machine Learning–Accelerated Discovery of Earth-Abundant Bimetallic Electrocatalysts for the Hydrogen Evolution Reaction
Ismail Can Oğuz, Nabil Khossossi, Marco Brunacci, Haldun Bucak, Süleyman Er
Abstract
High Resolution Image Download MS PowerPoint Slide Despite platinum’s well-established catalytic activity for the hydrogen evolution reaction (HER), its limited supply and steep cost hinder large-scale adoption. Earth-abundant bimetallic alloys thus emerge as attractive substitutes, though their vast compositional and structural diversity makes exhaustive density functional theory (DFT) screening unfeasible. Here, we introduce a machine learning (ML)–DFT workflow for the discovery and prioritization of bimetallic HER catalysts. By integrating EquiformerV2 into the AdsorbML surrogate-DFT pipeline, we efficiently predict hydrogen adsorption energies on thousands of alloy surfaces. Sabatier-volcano filtering combined with targeted DFT validation yields a mean absolute error of 0.12 eV across the screened space. Two surface motifs stand out: (i) transition-metal dimers or isolated top sites embedded in Sn- or Sb-rich layers, and (ii) Cu-rich surfaces (Cu–Sn, Cu–Sb) featuring Cu–Cu bridge or hollow sites without direct Sn or Sb interaction. A multiobjective assessment of activity, stability, and cost highlights four synthesis-ready candidates─Fe 2 Sb 4, Cu 6 Sb 2, Cu 6 Sn 2, and Ni 2 Sb 2 ─which combine platinum-like performance with significantly lower material costs. This integrated ML–DFT strategy transforms an otherwise intractable chemical landscape into a concise, experimental roadmap for earth-abundant HER catalyst development.