Hydrogen production from ammonia decomposition over Ru/Co–Al-LDOs catalysts prepared by a one-step synthesis method of co-precipitation

The design of efficient ammonia cracking catalysts is the key to developing ammonia as a hydrogen storage carrier. This paper investigated the role of Co–Al hydrotalcite carriers in ruthenium-based catalysts. Ru/Co–Al catalysts were prepared by mechanical milling, impregnation, and co-precipitation, and the catalytic activity and physicochemical properties of the catalysts were investigated, respectively. The catalysts prepared by the co-precipitation method exhibit the maximum specific surface area and metal dispersion due to the layered structure of LDH and the homogeneity of the co-precipitation method. In this study, it is concluded that the substitution of Ru during the co-precipitation preparation builds up strong metal-carrier interactions and generates a large number of oxygen vacancies. The catalyst prepared by the co-precipitation method exhibited a high H 2 generation rate (19.5 mmol·gcat −1 ·min −1 ) at GHSV = 30,000 ml·gcat −1 ·h −1 and 450 °C, and the performance remained stable after 50 h of reaction. This work provides a new idea for designing efficient Ru-based catalysts.