The strong Mo–N bond restrains the catalytic activity of metallic Mo in ammonia synthesis. In this study, the semi-empirical calculations in conjunction with the density functional theory calculations, Brønsted–Evans–Polanyi relationship and microkinetic modeling were used to evaluate the rate of ammonia synthesis on model active sites of Mo-based alloys, nitrides, and clusters with a modified Mo–N bond. It was found that active sites of binary alloys Mo_δMe_1−δ (0 ≤ δ ≤ 1; Me = Co, Pt, Ir, Rh) show the synergetic behavior. The sites of ternary Mo₃Me₃N (Me = Mo, Co, Pt, Ir) and Mo₂N-type nitrides revealed higher activities than sites on Mo planes due to an extra Mo bond with the lattice N atom. The sites of octahedral clusters Mo₃Me₃N (Me = Mo, Co, Ir, Pt) exhibited higher catalytic activity than the sites of nitrides because their Me–N bonds are weaker than Mo–N. It was also found that tetragonal Mo₂Me₂ (Me = Co, Pt, Ir) and bi-tetragonal clusters Mo₃Me₂ (Me = Co, Ir, Pt) are the best cases because their sites provide the optimal combination of local structure and thermodynamics. Catalytic activities of the most active sites, relative to the Fe–C₇ center, were found to change in the row 18.4 (threefold site Mo₂Ir₁ in cluster Mo₃Ir₂), 7.3 (Mo₂ in cluster Mo₂Ir₂), 3.9 (Mo₂Pt₁ in cluster Mo₃Ir₃N), 3.8 (M₃ on alloy Mo_0.78Ir_0.22), 2.0 [Mo₃Pt₁ on the plane (100) of Mo₃Pt₃N], 0.57 [Mo₃ on the plane (111) of Mo₂N], and 0.03 [Mo₄ on the plane Mo(110)–(1 × 2)]. The design of tailor-made catalytic sites suggested in this paper can probably be applied to other catalytic systems.

强大的Mo–N键抑制了金属Mo在氨合成中的催化活性。在这项研究中，结合密度泛函理论计算，Brønsted–Evans–Polanyi关系和微动力学模型的半经验计算被用于评估Mo基合金，氮化物和团簇模型活性部位上氨的合成速率。带有修饰的Mo–N键。据发现，二元合金的活性位点的Mo _δ我_1-δ（0≤δ≤1;我 = CO，铂，铱，铑）示出了协同行为。三元Mo ₃ Me ₃ N（Me  = Mo，Co，Pt，Ir）和Mo _2的位点由于与晶格N原子的额外Mo键，N型氮化物的活度高于Mo平面上的位。八面体簇Mo ₃ Me ₃ N（Me  = Mo，Co，Ir，Pt）的位点比氮化物的位点表现出更高的催化活性，因为它们的Me –N键比Mo–N弱。还发现四方Mo ₂ Me ₂（Me  = Co，Pt，Ir）和双四方簇Mo ₃ Me ₂（Me  = Co，Ir，Pt）是最好的情况，因为它们的位点提供了局部的最佳组合。结构和热力学。相对于Fe–C，最活跃位点的催化活性₇中心，被发现变化的行18.4（三重站点沫₂的Ir ₁在簇沫₃的Ir ₂），7.3（莫₂在簇沫₂的Ir ₂），3.9（莫₂的Pt ₁在簇沫₃的Ir ₃ N），3.8（中号₃上合金的Mo _0.78的Ir _0.22），2.0 [沫₃的Pt ₁上的钼的平面（100）₃的Pt ₃，0.57 [N]的Mo ₃上Mo的（111）面₂ N]和0.03 [平面Mo（110）–（1×2）上的Mo ₄ ]。本文建议的量身定制的催化位点的设计可能可以应用于其他催化体系。