Confinement effects over Ni-based catalysts for methane dry reforming

Methane dry reforming converts two greenhouse gases to produce versatile syngas that serves as a feedstock for chemical production while also contributing to closing the anthropogenic carbon cycle. Due to the excellent catalytic performance of Ni-based catalysts, they are widely used in methane dry reforming reactions. However, Ni-based catalysts suffer from a tendency to sinter and coke under high reaction temperatures, which severely restricts their industrial applications. This review presents the application of the confinement effect in improving the resistance to sintering and coking of Ni-based catalysts for methane dry reforming. Firstly, the mechanisms of catalyst deactivation, i.e., the origin of coking and sintering, are reviewed. Secondly, the catalyst synthesis strategies of surface spatial confinement, core-shell structure confinement, and sandwich structure confinement are presented. The influence of different kinds of confinement effects on improving the performance of Ni-based catalysts against sintering and coking are analyzed and summarized, elucidating the mechanisms and structure-performance relationships. This work provides a tutorial for designing Ni-based catalysts with anti-sintering/coking properties. Advances in application of the confinement effect in improving the resistance to sintering and coking of Ni-based catalysts for methane dry reforming were summarized.