Topologically immobilized catalysis centre for long-term stable carbon dioxide reforming of methane

Abstract

Methane reforming at low temperatures is of growing importance to mitigate the environmental impact of the production of synthesis gas, but it suffers from short catalyst lifetimes due to the severe deposition of carbon byproducts. Herein, we introduce a new class of topology-tailored catalyst in which tens-of-nanometer-thick fibrous networks of Ni metal and oxygen-deficient Y₂O₃ are entangled with each other to form a rooted structure, i.e., Ni#Y₂O₃. We demonstrate that the rooted Ni#Y₂O₃ catalyst stably promotes the carbon-dioxide reforming of methane at 723 K for over 1000 h, where the performance of traditional supported catalysts such as Ni/Y₂O₃ diminishes within 100 h due to the precluded mass transport by accumulated carbon byproducts. In situ TEM demonstrates that the supported Ni nanoparticles are readily detached from the support surface in the reaction atmosphere, and migrate around to result in widespread accumulation of the carbon byproducts. The long-term stable methane reforming over the rooted catalyst is ultimately attributed to the topologically immobilized Ni catalysis centre and the synergistic function of the oxygen-deficient Y₂O₃ matrix, which successfully inhibits the accumulation of byproducts.