Constructing thermally stable nickel sub-nanoparticles via in situ hydroxyl trapping for methane dry reforming

Abstract

Nickel based catalysts are widely utilized in methane dry reforming (DMR) reaction, and their catalytic properties are mainly determined by the dispersibility and anti-sintering ability of Ni species on catalyst supports. However, developing small size and stable nickel catalysts with strong resistance to particle sintering still remains challenge. Herein, vapor-phase-trapping technology is innovatively applicated at elevated temperature to prepare ultra-small size and highly dispersed Ni sub-nanoparticles on the SBA15 within rehydroxylation modification. The nickel vapor originated from precursors of acetylacetonate nickel is in situ captured by terminal hydroxyl groups on the surface of support at high temperature, realizing the uniform dispersion of nickel species as well as moderate interactions between nickel species and support. The highly dispersed and extra-small size Ni sub-nanoparticles of 1.94 nm with appropriate metal-support interaction contribute to excellent catalytic activity and lifetime of 150 h for DMR reaction. This work provides a rational design and precise modulation of efficient nickel-based catalyst.