Proximity-Engineered Dual-Atomic Cobalt Sites Enable Adaptive Spin Catalysis for Simultaneous Oxygen and Peroxide Reduction.

Abstract

Breaking the intrinsic adsorption conflicts among oxygen intermediates remains a central challenge in oxygen reduction reaction (ORR) electrocatalysis. Although spin-state engineering offers an effective strategy for tuning catalytic activity, conventional approaches generally focus on a single-spin configuration, which cannot simultaneously satisfy the distinct energetic requirements of different ORR intermediates. Here, we introduce an adaptive spin catalysis concept through proximity engineering of dual-atomic Co sites confined within a one-dimensional covalent organic framework. Precisely regulating the Co-Co separation while preserving the local coordination environment induces inter-site electronic coupling, giving rise to coexisting high-spin and low-spin Co configurations. Combined spectroscopic characterizations and theoretical calculations support a mechanistic framework in which these coexisting spin configurations provide complementary catalytic functions for distinct intermediates along the multistep ORR pathway, thereby alleviating adsorption conflicts. Consequently, the proximity-engineered catalyst delivers outstanding ORR activity with a half-wave potential of 0.96 V versus reversible hydrogen electrode, outperforming both its spatially separated counterpart and commercial Pt/C. The catalyst also efficiently mediates both O2 and H2O2 reduction while suppressing peroxide decomposition, enabling enhanced performance in rechargeable zinc-air batteries and peroxide-assisted aluminum-air batteries. This work establishes a molecular framework for exploiting spin-state complementarity in atomic catalysts for advanced energy-conversion reactions.