Low-temperature and high-efficiency ammonia decomposition catalyst, preparation method and application thereof

A preparation method of a low-temperature and high-efficiency ammonia decomposition catalyst, comprising:

• (1) preparing a composite support SBA-15/graphene by sol gel method;
• (2) mechanically mixing a nickel precursor salt and the composite support SBA-15/graphene in an aqueous solution, drying an obtained mixture and calcinating a dried mixture in an ammonia atmosphere to obtain the low-temperature and high-efficiency ammonia decomposition catalyst;
• wherein the nickel precursor salt in step (2) is any one of Ni(OH)2, Ni(CH3COO)2·4H2O and nickel acetylacetonate;
• a condition of the calcinating is as follows:
• under a high-purity ammonia gas atmosphere with a flow rate of 10-50 ml·min−1, the temperature is raised to 400° C. at 1-10° C.·min−1 and kept for 10 min, and then the temperature is raised to 500-700° C. at 1-5° C.·min−1 and kept for 2 h.