Strong Metal–Support Interactions in Ni/KCC-1 Catalysts for Base-Growth Carbon Nanotubes in Methane Decomposition

Catalytic decomposition of methane (CDM) offers a low-carbon approach to utilizing the greenhouse gas CH 4 while producing highly demanded hydrogen. Concurrently, carbon nanotubes (CNTs) hold great industry value and find applications in fuel cells, electrodes, and energy storage devices. In this study, Ni-based catalysts supported on dendritic fibrous nanosilica (DFNS; KCC-1) were synthesized, leveraging the unique fibrous structure of KCC-1 to enhance metal–support interactions and promote the dispersion of Ni nanoparticles. Compared to Ni supported on nonporous spherical Stöber silica, Ni/KCC-1 with enhanced metal–support interactions facilitated the base-growth mechanism of CNTs, a desirable feature for catalyst regeneration. The stronger metal–support interactions originate from higher fractions of 2:1 Ni-phyllosilicates, which are facilitated by the slit-like silica sheets of KCC-1 that can sandwich Ni species, acting as a silica sacrificial template. The consequential effect of promoting base-growth CNTs via phyllosilicates onto reaction activities was deeply studied, with catalyst characterizations, including H 2 -TPR, TEM–EDX, CH 4 -TPSR, TGA, XPS, in situ XAS, and in situ DRIFTS employed to give insights into the influence of support morphology on the catalytic performance in CDM.