CeO_2-x modified Ru/-Al₂O₃ catalysts for ammonia decomposition reaction

Developing high-performance ammonia decomposition catalysts for preparing COx-free hydrogen shows great practical significance. Herein, CeO2 is used as a promoter to modulate the metal-support interaction to enhance the catalytic performance of Ru/Al2O3 catalysts. A series of 1Ru/xCe-10Al (x = 0.5, 1, or 3) catalysts was prepared by a facile colloidal deposition method. We find that the optimized 1Ru/1Ce-10Al catalyst exhibits excellent activity for the decomposition of ammonia with a very high hydrogen yield of 7097 mmol(H2)/(g(Ru).min) at 450 degrees C. It is confirmed that Ru species are highly dispersed on the support surface as stable small clusters (similar to 1.3 nm). More importantly, due to the interaction between Ru species and partially reduced CeO2-x, the electron density of Ru species is increased, which is beneficial to the high activity of the 1Ru/xCe-10Al catalysts. This work paves a way to construct high-efficiency ammonia decomposition catalysts modified by CeO2. (c) 2023 Published by Elsevier B.V. on behalf of Chinese Society of Rare Earths.