Developing non-precious metal catalysts to selectively reduce functionalized nitroarenes with high efficiency is urgently desirable for the production of value-added amines. Herein, we report a novel, efficient, anti-poisoning single-atom cobalt catalyst (Co-NAC) for the highly selective hydrogenation of the nitro to amino group for nitroarenes baring various functional groups, including vinyl, cyano, and halogen. Using a combination of structure characterization techniques, we have confirmed that the cobalt species are predominantly present in the form of four-coordinated Co single sites anchored on nitrogen-assembly carbon (NAC) as the ordered mesoporous support. Co-NAC catalysts enable the full conversion and > 99% selectivity with molecular H₂ as a green reductant under mild conditions (80 °C, 2 MPa H₂). As for the selective hydrogenation of 3-nitrostyrene, Co-NAC catalyst affords high catalytic productivity (19.7 h⁻¹), which is superior to the cobalt nanoparticles (NPs) catalysts and most of the recently reported Co-based catalysts. This is attributed to the highly accessible atomically-dispersed Co active sites, the high surface area with ordered-mesoporous morphology and the prominent high content of nitrogen dopants. Notably, Co-NAC catalyst displays resistance towards sulfur-containing poisons (20 equivalents) and strong non-oxidizing acid (8 M), showing great potential for continuous application in the chemical industry.

We report a facile strategy to synthesize intermetallic nanoparticle (iNP) electrocatalysts via one-pot pyrolysis of a zeolitic imidazolate framework, ZIF-8, encapsulating precious metal nanoparticles (NPs). ZIF-8 serves not only as precursor for N-doped carbon (NC), but also as Zn source for the formation of intermetallic or alloy NPs with the encapsulated metals. The resulting sub-4 nm PtZn iNPs embedded in NC exhibit high sintering resistance up to 1, 000 ℃. Importantly, the present methodology allows fine-tuning of both composition (e.g., PdZn and RhZn iNPs, as well as AuZn and RuZn alloy NPs) and size (2.4, 3.7, and 5.4 nm PtZn) of the as-formed bimetallic NPs. To the best of our knowledge, this is the first report of a metal-organic framework (MOF) with multiple functionalities, such as secondary metal source, carbon precursor, and size-regulating reagent, which promote the formation of iNPs. This work opens a new avenue for the synthesis of highly uniform and stable iNPs.