Unveiling the Mechanisms Ruling the Efficient Hydrogen Evolution Reaction with Mitrofanovite Pt₃Te₄

By means of electrocatalytic tests, surface-science techniques and density functional theory, we unveil the physicochemical mechanisms ruling the electrocatalytic activity of recently discovered mitrofanovite (Pt₃Te₄) mineral. Mitrofanovite represents a very promising electrocatalyst candidate for energy-related applications, with a reduction of costs by 47% compared to pure Pt and superior robustness to CO poisoning. We show that Pt₃Te₄ is a weak topological metal with the $$ invariant, exhibiting electrical conductivity (∼4 × 10⁶ S/m) comparable with pure Pt. In hydrogen evolution reaction (HER), the electrode based on bulk Pt₃Te₄ shows a very small overpotential of 46 mV at 10 mA cm^-2 and a Tafel slope of 36-49 mV dec^-1 associated with the Volmer-Heyrovsky mechanism. The outstanding ambient stability of Pt₃Te₄ also provides durability of the electrode and long-term stability of its efficient catalytic performances.