Frontispiece: Cation Exchange-Driven Grain Boundary-Rich Nanorings as Efficient CO2 Reduction Electrocatalysts

Grain boundary engineering offers a new paradigm for boosting CO₂ electroreduction. As highlighted in this image, grain boundary-rich SnS nanorings serve as a highly efficient “formate factory”. CO₂ molecules are transported to grain boundary regions, which act as entrances to high-speed catalytic pathways where formate production is strongly accelerated. Outside these boundaries, the reaction proceeds less efficiently, as reported by Yang Liu et al. in their Research Article (e202510973).