Development of high-density single atoms site (SAs) electrocatalysts is highly desirable due to their extraordinary catalytic performance. However, their synthesis is still challenging and their anticorrosion capacities in electrolyte (particularly in acidic electrolyte) are unsatisfying. Herein, we have constructed N,S co-doped carbon to anchor ~ 10 wt.% Co SAs (Co-SAs/NSC) via a novel polymerization–sulfurization–pyrolysis strategy toward selective electro-oxidation of thioethers in acidic solution. The as-obtained Co SAs has a coordination geometry of Co-S₂N₄, exhibiting excellent electrocatalytic activity and robust stability. At a low potential of 1.40 V vs. reversible hydrogen electrode (RHE), the conversion rate of thioethers over Co-SAs/NSC reaches 99.7% with 100% selectivity and 100% Faraday efficiency (FE) for producing sulfoxide, which is higher than the commercial Pt electrode and the reported state-of-the-art catalysts. Theoretical calculations and experiments reveal that the Co-S₂N₄ structure endows the outstanding electro-oxidation activity of Co SAs through significantly promoting desorption of the products. This work presents a convenient strategy to build high-performance SAs catalysts for the resourceful use of sulfur-containing pollutants.

Electrochemical nitrogen reduction reaction (NRR) under ambient conditions is highly desirable to achieve sustainable ammonia (NH₃) production via an alternative carbon free strategy. Single-atom catalysts (SACs) with super high atomic utilization and catalytic efficiency exhibit great potential for NRR. Herein, a high-performance NRR SAC is facilely prepared via a simple deposition method to anchor Au single atoms onto porous β-FeOOH nanotubes. The resulting Au-SA/FeOOH can efficiently drive NRR under ambient conditions, and the NH₃ yield reaches as high as 2,860 μg·h⁻¹·mg_Au⁻¹ at −0.4 V vs. reversible hydrogen electrode (RHE) with 14.2% faradaic efficiency, much superior to those of all the reported Au-based electrocatalysts. Systematic investigations demonstrate that the synergy of much enhanced N₂ adsorption, directional electron export, and mass transfer ability in Au-SA/FeOOH greatly contributes to the superior NRR activity. This work highlights a new insight into the design of high efficient NRR electrocatalysts by combination of porous metal oxide matrix and highly active single-atom sites.