Catalytic Methane Decomposition over Bimetallic Transition Metals Supported on Composite Aerogel

Abstract

Bimetallic transition metals over single Al2O3 support and TiO2·Al2O3 composite support aerogel catalysts (9Ni-1Co/Al2O3 and 9Ni-1Co/Al2O3·TiO2) were synthesized by the sol–gel technique and tested in the methane decomposition reaction for production of COx-free hydrogen and base-growth carbon nanotubes (CNTs). Compared to monometallic catalysts and other bimetallic catalysts with different Ni/Co molar ratios such as 5Ni-5Co/Al2O3, 3Ni-7Co/Al2O3, and 1Ni-9Co/Al2O3, mesoporous 9Ni-1Co/Al2O3 aerogel catalysts have higher catalytic activity and stability. Furthermore, aerogel catalysts (9Ni-1Co/Al2O3·TiO2) consisting of bimetallic transition metals supported on TiO2·Al2O3 composite support displayed higher catalytic performance than 9Ni-1Co/Al2O3 aerogel catalyst. These results indicated that metal sintering phenomena on bimetallic transition metals was less severe than monometallic; meanwhile, the composite support improved metal dispersion, leading to higher utilization of metal species which enhanced the ...