Amid the global drive toward carbon neutrality, efficiently and selectively converting carbon dioxide (CO2) into useful chemicals remains a challenge.
A collaborative research team led by Prof. LIU Yuefeng from the Dalian Institute of Chemical Physics (DICP) of the Chinese Academy of Sciences, Prof. KANG Hui from Chengdu University, Prof. ZHANG Riguang from Taiyuan University of Technology, and Prof. Gabriele Centi from Messina University, has developed a gas-induced structure evolution strategy, creating a "self-transforming" catalyst that redefines CO2 hydrogenation. The study was published in Nature Communications.
Researchers uncovered a Co-Mn interface-driven, reaction-induced carbon restructuring effect on cobalt-based nanoclusters. By engineering a 2Co/MnOx catalyst, where cobalt nanoclusters with a 2 wt% loading are supported on manganese oxide, they achieved a targeted switch of product selectivity in CO2 hydrogenation, shifting the dominant product from methane (CH4) to carbon monoxide (CO). This study has boosted the CO/CH4 product ratio from an initial 0.89 to 13.4, with CO selectivity surging from 45.7% to 94.0% within just 5 hours of reaction.
Furthermore, researchers decoded the underlying mechanism: the core of this effect lies in the unique Co-C-O-Mn bridge adsorption sites formed at the Co-MnO interface. These sites drive the dissociation of CO, generating polymeric carbon species that modify the cobalt nanoclusters, suppressing the secondary adsorption and hydrogenation of CO intermediates, ultimately enabling ultrahigh CO selectivity. Remarkably, this carbon-modified structure is fully reversible: treatment with H2 at 500 oC can remove the polymeric carbon species, restoring the catalyst's initial CH4 selectivity, offering unprecedented flexibility for industrial catalytic regulation.
Cobalt-based nanoclusters are core active components for critical industrial catalytic reactions, but structural evolutions like coking during reactions have long been regarded as a primary cause of catalyst deactivation. This study shatters that traditional perception, turning reaction-induced structural changes into a powerful tool for tuning catalytic selectivity. It reveals a restructuring mechanism entirely distinct from conventional cobalt carbide or carbon-encapsulated cobalt systems, providing a brand-new design principle for developing highly selective, CO-poisoning-resistant cobalt-based catalysts.
Reaction-induced catalyst structural evolution is a common phenomenon in heterogeneous catalysis, and this study paves the way for its precise, targeted utilization. Moving forward, researchers will expand this strategy to key industrial reactions, including C1 catalysis, Fischer-Tropsch synthesis, and alkane conversion, delivering more efficient catalytic systems to unlock the high-value transformation of CO2 and other small energy molecules, powering the global transition to a carbon-neutral future.