Coke-free methane dry reforming over nano-sized NiO-CeO2 solid solution after exsolution

Exsolution as a method for catalyst preparation is generally only studied in perovskites or similar systems, which puts a constraint on the catalyst support composition, owing to size and charge balance effects. We show that Ni nanoparticle growth occurs via the exsolution mechanism from a NiO-CeO2 solid solution with the fluorite structure to form the supported Ni/CeO2 catalyst. This supported catalyst showed high methane dry reforming activity and coke-free performance at 800 °C and using 50 vol% CH4/50 vol% CO2 feed gas composition and 5000 Lkgcat−1 h−1. The use of solid-solutions such as these can therefore expand the variety of catalyst supports which could provide coke-free performance under dry reforming reaction conditions. [Display omitted] •Ni growth from NiO-CeO2 occurs via exsolution and not grain-grown precipitation.•The catalyst support interface is consistent with exsolution from perovskites.•The resulting Ni/CeO2 catalyst was coke-free for 50 h for methane dry reforming.