Rare Earth Elements (La, Ce, Pr) Modified Co/NC Catalyst for Efficient and Stable Ammonia Decomposition to Hydrogen Production

Co/NC catalysts modified with rare earth elements (La, Ce, Pr) were prepared by pyrolysis of rare earth elements doped ZIF-67. The experimental results show that the modification of rare earth elements significantly improves the ammonia decomposition activity and stability of the Co/NC catalyst. The La-Co/NC catalyst can achieve an 82.3% ammonia decomposition and 18.4 mmol hydrogen production rate at 550 °C with a GHSV of 20 000 cm³·h⁻¹. Furthermore, no obvious performance degradation is observed after 72 hours of reaction for all rare earth elements modified catalysts. It is shown that the modification of rare earth elements significantly improves the surface alkalinity and surface chemical state of the catalyst, and thus improves the ammonia decomposition activity of the catalyst. A new type of high-performance ammonia decomposition Co-based catalyst is proposed, and the promoting effect of rare earth elements on the activity of ammonia decomposition is revealed.