Rare‐Earth Single Erbium Atoms for Enhanced Photocatalytic CO₂ Reduction

The solar‐driven photocatalytic reduction of CO 2 (CO 2 RR) into chemical fuels is a promising route to enrich energy supplies and mitigate CO 2 emissions. However, low catalytic efficiency and poor selectivity, especially in a pure‐water system, hinder the development of photocatalytic CO 2 RR owing to the lack of effective catalysts. Herein, we report a novel atom‐confinement and coordination (ACC) strategy to achieve the synthesis of rare‐earth single erbium (Er) atoms supported on carbon nitride nanotubes (Er 1 /CN‐NT) with a tunable dispersion density of single atoms. Er 1 /CN‐NT is a highly efficient and robust photocatalyst that exhibits outstanding CO 2 RR performance in a pure‐water system. Experimental results and density functional theory calculations reveal the crucial role of single Er atoms in promoting photocatalytic CO 2 RR.