Exploring the stability of fe–ni alloy nanoparticles exsolved from double-layered perovskites for dry reforming of methane

Abstract

Exsolution is emerging as a promising route for the creation of nanoparticles that remain anchored to the oxide support, imparting remarkable stability in high temperature chemical processes such as dry reforming of methane. This process takes place at temperatures around 850 °C, which causes sintering-related issues in catalysts prepared using conventional impregnation methods, which could be overcome by using exsolution functionalized oxides. In this work, FeNi3 alloy nanoparticles exsolved from Sr2FexNi1-xMoO6-δ double-layered perovskites were evaluated as a dry reforming catalyst, paying special attention to structure–activity relationships. Our results indicate that increasing the Ni content favors the nanoparticle dispersion, eventually leading to increased CO2 and CH4 conversions. The exsolved nanoparticles presented remarkable nanoparticle size (ca. 30 nm) stability after the 10 h treatment, although the formation of some phase segregations over the course of the reaction caused a minor decrease in the nanoparticle population. Overall, the results presented here serve as materials processing guidelines that could find further potential use in the design of more efficient (electro)catalysts in other fuel production or energy conversion technologies.