Uniform one-dimensional hierarchical CoO_x-N-C feather duster breaking the activity-stability trade-off for hydrogenation reactions

Carbon-based non-precious metal/oxide catalysts always face the dilemma of a trade-off between high activity and long-term stability in hydrogenation reactions, detrimental to their practical applications. Herein we propose a unique and uniform feather duster-type catalyst as a promising concept to solve this activity-stability trade-off. The feather duster is composed of both exposed and embedded active sites, that can facilitate substrate adsorption/activation and can be resistant against site leaching during the non-neutral aqueous phase reactions. We constructed a uniform one-dimensional hierarchical transition metal oxide-containing N-doped carbon (TMO-N-C), especially for CoO_x-N-C (x = 1.0 or 1.3), based on a controlled depolymerization-reassembly strategy before morphology-conserved pyrolysis. The uniform, thermally stable feather duster-type precursor was induced in view of the interaction between cobalt 2-methylimidazolate framework (ZIF-67) polyhedron and zinc-trimesic acid (ZnBTC) fiber in water. And subsequent pyrolysis leads to a uniform CoO_x-N-C nanoarchitecture with numerous nanorods planted on a single fiber. The resulting CoO_x-N-C proves to be highly efficient for 4-nitrophenol reduction, delivering a high activity factor of 7.32 s⁻¹ g⁻¹ with exceptional long life over 10 cycles, thus ranking CoO_x-N-C one of the best transition metal oxide catalysts for hydrogenation reactions. This research overcomes the dilemma that either high activity contributed by surface active sites or superior stability provided by embedded ones, offering valuable guidance for rational design of efficient metal/oxide catalysts. © 2023 Elsevier B.V.