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.

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Remediation and reuse of discarded plastics can reduce their accumulation in the environment and bring energy savings for plastic production. Here we discover a binuclear zinc catalyst that features a biomimetic intramolecular pathway for polyester depolymerization, which not merely enables environmental degradation of PET but also affords industrial-scale PET recycling under relatively mild conditions. The binuclear catalyst delivers a speci c activity of 36 mg PET d -1 g catal -1 toward PET depolymerization at pH 8 and 40 o C, the very condition holding the possibility of naturally breaking down plastic waste. The structural stability of this synthetic catalyst allows it to work under wide operational conditions, resulting in a speci c activity of 577 g PET h -1 g catal -1 at pH 13 and 90 o C for centralized PET recycling. A closed-loop production of bottle-grade PET was also demonstrated. Besides, this catalyst is catalytically active toward a wide scope of substrates with high tolerance to additives and impurities.