Ni@CaTiO3 Nanocomposites for Methane Decomposition Into Hydrogen and Multiwalled Carbon Nanotubes

Abstract

Novel and economic supports were prepared to facilitate the NiO-reducibility and enrich the hydrogen production from the catalytic conversion of methane. Mixed (CaTi)-oxides of CaO %=10, 20, and 30 were synthesized by direct compositing of CaCO3 and one-pot synthesized (TiO2)-nanoparticles. The developed nanostructures were characterized by a high-resolution transmission electron microscope, X-ray diffraction (XRD), temperature programmed reduction (TPR), and N2 adsorption-desorption measurements. Practically, (Ni@30 % CaTiO3) the catalyst of cubic morphology, achieved a high hydrogen production ratio of 62.2 %. The incorporation of CaO to TiO2 hindered the formation of NiTiO3@NiCaTiO3 phases and facilitated the fast reduction of NiO-phase to Ni (as revealed by temperature programmed reduction (TPR) and XRD. The formation of well-ordered carbon nanotubes (CNTs) as valuable by-products was also possible by these nanocomposites. The developed catalysts exhibited remarkable catalytic and structural stabilities. These results reflect the effective use of abundant CaO inorganic salt to enrich the H2 production by (CaTiO3) supports for potential and green energy production.