Zirconia prepared from UIO-66 as a support of Ru catalyst for ammonia synthesis

The development of effective Ru catalyst for ammonia synthesis is of important practical value and scientific significance because of the wide application of ammonia as a fertilizer and its promising applications in the renewable energy. Generally, ZrO₂ was regarded as an inferior support for Ru catalyst used in ammonia synthesis. Here we prepare ZrO₂ with monoclinic phase and carbon species from ZrCl₄ following the preparation route of UiO-66 as well as ammonia treatment. Owing to the presence of a larger amount of hydrogen adsorption as well as the easier desorption of hydrogen species, the ill effect of hydrogen species on the nitrogen adsorption-desorption and ammonia synthesis can be effectively alleviated. The resulting ZrO₂-supported Ru catalyst showed 4 times higher ammonia synthesis activity than the conventional Ru/ZrO₂ obtained from zirconium nitrate.