LaNiO3 nanocube embedded in mesoporous silica for dry reforming of methane with enhanced coking resistance

Abstract

Methane dry reforming (DRM) is a fascinating reaction which can effectively utilize two abundant and greenhouse gases (CO2 and CH4) to prepare syngas (CO and H2). The design and synthesis of high coking resistance Ni based catalysts are still a challenge. Herein, a perfect perovskite LaNiO3 nano-cube was encapsulated in perpendicular mesoporous silica shell to form a novel core-shell structured catalyst (LaNiO3-cube@meso-SiO2) for DRM reaction. The morphology of LaNiO3-cube@meso-SiO2 retained well even after reduced at high temperature, and the effect of shell thickness on its catalytic performance was also studied in detail. It's found that the mesoporous silica shell has positively effects to improve the coking resistance of Ni/La2O3 (derived from LaNiO3 nano-cube after reduction). When the shell thickness increased, the formation of coking deposition is decreased. The reasons for this novel core-shell structured catalyst with superior DRM performance should be attributed to the dual confinement effects. One is the strong metal-support interaction (SMSI) between Ni and La2O3 and silica, and the other is derived from the perpendicular mesoporous silica shell. The dual confinement strategy developed in this work can be used to design other high coking resistance catalysts for DRM reaction or other high temperature thermal catalysts.