Effect of rare earth and other cationic promoters on properties of CoMoNx/CNTs catalysts for ammonia decomposition

Carbon nanotubes (CNTs) supported Co-Mo nitride catalysts were prepared by incipient-wetness impregnation method and temperature-programmed reaction in N2-H2 mixed gases. The effects of cationic promoters (K, Ba, La, Ce and Zr) on the catalytic performance and surface properties were investigated. All samples were characterized by N2 physical adsorption, X-ray diffraction, and temperature-programmed reduction of H2. The results showed that the addition of promoters reduced the crystallite size of Mo2N and Co3Mo3N species and increased their surface area and dispersion. Among the catalysts, the La promoted CoMoNx/CNTs catalyst had the highest ammonia conversion which could reach 97.63% at 600 °C.

Graphical AbstractCatalytic activities of the modified CoMoNx/CNTs catalysts (1)CoMoNx/CNTs;(2)K-CoMoNx/CNTs;(3)Ba-CoMoNx/CNTs;(4)La-CoMoNx/CNTs;(5)Ce-CoMoNx/CNTs;(6)Zr-CoMoNx/CNTsFigure optionsDownload full-size imageDownload as PowerPoint slide