1T/1H-SnS₂ Sheets for Electrochemical CO₂ Reduction to Formate

Abstract

Understanding the catalytic mechanism of highly active two-dimensional electrocatalysts is crucial to their rational design. Herein, we reveal the element dependence of the reactivity of two-dimensional metal dichalcogenide sheets for electrocatalytic CO₂ reduction. We found that tin(IV) disulfide (SnS₂) and molybdenum(IV) disulfide (MoS₂) sheets exhibited Faradaic efficiencies of 63.3% and ∼0%, respectively, for formic acid. Scanning electrochemical cell microscopy and theoretical calculations were used to identify the catalytically active sites of SnS₂ as terraces and edges. Owing to the effective utilization of the entire surface area, SnS₂ can effectively accelerate catalytic reactions. This finding provides a direction for material research in two-dimensional electrocatalysts for energy-efficient chemical production from electrochemical CO₂ reduction, as well as for other energy devices.