Promotion effect of the rare earth metals (cerium, lanthanum, and yttrium) on the catalytic performance of Ni/Al2O3 catalyst fabricate via the neoteric one-pot hydrothermal method for methane decomposition

Catalytic methane decomposition is an economical and green procedure to procreate COx-free hydrogen as a renewable energy source. This paper describes the mesoporous high surface area Ni/Al2O3 catalysts enhanced with the rare earth metals (cerium, lanthanum, and yttrium) fabricated via neoteric one-pot hydrothermal strategy, and the co-catalysts performance in the methane decomposition process, explores. This comparative study shows that Yttria exhibited dramatic catalytic activity and thermal stability among the above promoters. The maximum CH4 conversions of 61.16, 68.61, and 63.74 % have been obtained over the 50Ni-xY/Al2O3 (x = 2.5, 5, and 10 wt%) at 650 C-degrees and GHSV = 24000 mL.(h.gcat)(-1), respectively. The optimal sample (5 wt% Ydoped) reveals a superior lifetime in high-temperature stability tests after 10 h. Moreover, the analysis of carbon nanofiber's textural properties indicates that Y loading leads to highly graphitized (I-D/I-G = 1.22 to 0.98) and the formation of a carbon lattice with supreme crystallization.