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

Danil W Boukhvalov,Ivana Vobornik,Anan Bari Sarkar,Jun Fujii,Li-Min Wang,Antonio Politano,Mykhailo Vorokhta,Gopi Nath Daptary,Doron Naveh,Gianluca D’Olimpio,Amit Agarwal,Barun Ghosh,Kuan Hsu,Chin Shan Lue,Ori Azulay,Jia Cheng,François C Bocquet,Chia-Nung Kuo,Lixue Zhang

doi:10.1021/acs.jpclett.1c01261

Abstract

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.

Highlights

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
hydrogen evolution reaction (HER) enables achieving ultrapure hydrogen.[1−5] HER is the cathodic reaction in electrochemical water splitting (2H2O → 2H2 + O2).[1,2,5]
As a matter of fact, being van der Waals materials, they can be thinned down to atomic thickness by liquid-phase exfoliation, with the possibility to achieve nanosheets with high surface area and superior catalytic activity.[14−16] Especially, the transition-metal dichalcogenides (TMDs) PtX2 (X = S, Se, Te), which crystallize in the same structure as the naturally occurring mineral “moncheite” hosts pronounced chemical/ structural flexibility.[17,18]