High-entropy alloy ammonia synthesis catalyst as well as preparation method and application thereof

The invention discloses a high-entropy alloy ammonia synthesis catalyst which comprises a carrier and high-entropy alloy particles loaded on the surface of the carrier, the average particle size of the high-entropy alloy particles is 2-20 nm, and the loading capacity of the high-entropy alloy particles is 5-70 wt%; the high-entropy alloy particles comprise active metal and auxiliary metal; the active metal comprises at least three of Fe, Co, Mo, Ru, Os, Ni, Rh, Ir, Mn, Re, Pt, Pd and Ag; the auxiliary metal comprises at least one of Ce, Ba, Sr, Mg, Ca, Li, K, La, Sm, W, V, Cs, Tc and Cu. The preparation method of the high-entropy alloy ammonia synthesis catalyst comprises the following steps: uniformly mixing an active metal salt, an auxiliary metal salt, an organic ligand and a carrier, carrying out ball milling in an inert atmosphere to obtain a precursor A, and carrying out heat treatment, reduction and cooling in the inert atmosphere to obtain the high-entropy alloy ammonia synthesis catalyst. The high-en