Size structure–catalytic performance correlation of supported Ni/MCF-17 catalysts for COx-free hydrogen production

Abstract

Herein, supported Ni/MCF-17 catalysts with the size of nickel nanocrystal in the range of 1.5–8.0 nm were synthesized and employed for CO_x-free hydrogen production for fuel cells via the ammonia decomposition reaction. Characterized by a variety of techniques, the results show that nickel particles are in a highly dispersed state with a uniform particle size for each catalyst. Furthermore, the influence of particle size on the catalytic performance has been investigated. It was later revealed that Ni nanoparticles with different particle sizes exhibited significant differences in catalyzing the CO_x-free hydrogen production reaction. Moreover, the catalyst with the Ni nanoparticle size around 3.0 nm exhibited highest catalytic activity at each reaction temperature; this could be explained by the presence of high B₅ active sites on the Ni-based catalyst surface.