Engineering Fe–Ni Dual-Atom Sites Via Ru Nanoclusters on 3D Carbon Aerogel for Enhanced Bifunctional Oxygen Electrocatalysis

Dual-atom catalysts (DACs) show great promise in catalyzing oxygen reduction/evolution reactions (ORR/OER), yet facing significant challenges in achieving simultaneous high catalytic activity and stability in zinc–air batteries (ZABs). In this study, we synthesized a porous three-dimensional carbon aerogel anchored with atomically isolated FeN4/NiN4 dual sites and Ru6 nanoclusters (FeN4–Ru6–NiN4@PCA) to address these challenges. The adjacent Ru6 nanoclusters effectively regulate the geometric structures of FeN4 and NiN4 sites and catalyze the formation of a highly graphitic carbon matrix. These structural features endow FeN4–Ru6–NiN4@PCA with remarkable ORR/OER activity and stability, outperforming counterparts with only FeN4/NiN4 dual species and benchmark Pt/C and RuO2 catalysts. Density functional theory calculations reveal that Ru6 clusters induce obvious electron redistribution of FeN4/NiN4 sites and optimize their electron transfer to the key oxygen intermediates (OH*) at the rate-determining steps, thereby accelerating the ORR and OER kinetics. When employed FeN4–Ru6–NiN4@PCA as the cathode catalyst in ZABs, the resulting ZAB delivers a peak power density of 197.76 mW cm–2 and demonstrates outstanding cycling stability over 2000 h, highlighting its great potential for use in applications of energy storage device.