Ultrafast energy-neutral molecular oxygen activation via atomically-adjacent bimetallic catalytic sites

Activating ground-state molecular oxygen (O2) without added oxidants or external energy is a central challenge in aerobic catalysis because triplet O2 imposes spin and electron-transfer constraints. Herein, we report a high-rate, energy-neutral O2 activation platform that converts ambient air O2 directly to singlet oxygen (1O2) under room-temperature, bias-free conditions. By engineering atomically adjacent Co-Mo dual sites, Co-Mo d-d coupling and electron delocalization create a short-range electron transfer pathway that strengthens O2 adsorption, weaken the O-O bond via π* orbital population, and limit solvent-induced dissipation, thereby favoring selective 1O2 formation. These features enable the catalyst 1O2 productivity and pollutant degradation rates up to three orders of magnitude higher than previously reported air-fed O2 heterogeneous catalysts and comparable to oxidant-driven processes, yet without chemical inputs or energy bias. The catalyst is robust and versatile across diverse applications, including the degradation of organic contaminants, transformation of inorganic ions and antibacterial applications. This work establishes a new approach for sustainable O2 activation, pointing toward next-generation energy-neutral catalytic technologies. Activating ground-state molecular oxygen without added oxidants or external energy remains a major challenge in aerobic catalysis. Here, the authors present a high-rate, energy-neutral O₂ activation platform that directly generates singlet oxygen from ambient air under room-temperature, bias-free conditions.