The development of high-efficiency and durable bifunctional electrocatalysts for both the oxygen reduction reaction (ORR) and oxygen evolution reaction (OER) is critical for the widespread application of rechargeable zinc–air (Zn–air) batteries. This calls for rational screening of targeted ORR/OER components and precise control of their atomic and electronic structures to produce synergistic effects. Here, we report a Mn-doped RuO2 (Mn-RuO2) bimetallic oxide with atomic-scale dispersion of Mn atoms into the RuO2 lattice, which exhibits remarkable activity and super durability for both the ORR and OER, with a very low potential difference (ΔE) of 0.64 V between the half-wave potential of ORR (E 1/2) and the OER potential at 10 mA cm–2 (E j10) and a negligible decay of E 1/2 and E j10 after 250 000 and 30 000 CV cycles for ORR and OER, respectively. Moreover, Zn–air batteries using the Mn-RuO2 catalysts exhibit a high power density of 181 mW cm–2, low charge/discharge voltage gaps of 0.69/0.96/1.38 V, and ultralong lifespans of 15 000/2800/1800 cycles (corresponding to 2500/467/300 h operation time) at a current density of 10/50/100 mA cm–2, respectively. Theoretical calculations reveal that the excellent performances of Mn-RuO2 is mainly due to the precise optimization of valence state and d-band center for appropriate adsorption energy of the oxygenated intermediates.

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Heterogeneous catalysts containing diatomic sites are often hypothesized to have distinctive reactivity due to synergistic effects, but there are limited approaches that enable the convenient production of diatomic catalysts (DACs) with diverse metal combinations. Here, we present a general synthetic strategy for constructing a DAC library across a wide spectrum of homonuclear (Fe 2 , Co 2 , Ni 2 , Cu 2 , Mn 2 , and Pd 2 ) and heteronuclear (Fe−Cu, Fe−Ni, Cu−Mn, and Cu−Co) bimetal centers. This strategy is based on an encapsulation−pyrolysis approach, wherein a porous material-encapsulated macrocyclic complex mediates the structure of DACs by preserving the main body of the molecular framework during pyrolysis. We take the oxygen reduction reaction (ORR) as an example to show that this DAC library can provide great opportunities for electrocatalyst development by unlocking an unconventional reaction pathway. Among all investigated sites, Fe−Cu diatomic sites possess exceptional high durability for ORR because the Fe−Cu pairs can steer elementary steps in the catalytic cycle and suppress the troublesome Fenton-like reactions.