Atomically dispersed Sn modified with trace sulfur species derived from organosulfide complex for electroreduction of CO2

Electrochemical CO2 conversion into fuels is highly desirable to achieve carbon artificial cycles. Among electrocatalyst candidates, earth-abundant tin is subject to unsatisfied efficiency and selectivity. In this work, atomically-dispersed Sn nanoclusters modified with the trace of sulfur doping are proposed to efficiently electroreduce CO2 to C1 chemicals. This electrocatalyst is in situ derived from bis(benzene-1,2-dithiolato). It exhibits a high Faradaic efficiency (90%) for carbonaceous products at a moderate overpotential (0.75 V). Importantly, it is exploited for the formate formation with unprecedented partial current density (90 mA cm−2) and long-term stability (50 h) using the flow cell, better than most Sn-based catalysts. Electrochemical experiments and theoretical calculations manifest the promoting effect of trace sulfur on Sn nanoclusters, which stabilizes the *HCOOH intermediate and favors CO2 electroreduction. Hence, it emphasizes the importance of dopants and charge modulating for performance enhancement. This work unfolds a promising candidate for Sn electrocatalysts towards CO2 electroreduction.