Activating high-energy multiple bonds using earth-abundant metals is one of the most significant challenges in catalysis. Here, we show that LaCoSi—a ternary intermetallic compound—is an efficient and stable catalyst for N₂ activation to produce NH₃. The ammonia synthesis is significantly promoted by shifting the reaction bottleneck from the sluggish N₂ dissociation to NH _x formation, which few catalysts have achieved. Theoretical calculations reveal that the negatively charged cobalt mediates electron transfer from lanthanum to the adsorbed N₂, which further reduces the activation barrier of N₂ dissociation. Most importantly, the specific LaCoSi geometric configuration stabilizes the N₂ adsorption with a strong exothermic effect, which dramatically decreases the apparent energy barrier of N₂ activation. Consequently, LaCoSi shows a superior activity (1,250 μmol g⁻¹ h⁻¹), with a 60-fold increase over the activity of supported cobalt catalysts under mild reaction conditions (400 °C, 0.1 MPa).

使用富含地球的金属激活高能多键是催化领域最重大的挑战之一。在这里，我们表明LaCoSi（一种三元金属间化合物）是一种有效，稳定的N ₂活化生成NH _3的催化剂。通过将反应瓶颈从缓慢的N ₂离解转变为NH _x形成，可以显着促进氨的合成，而这几乎是没有催化剂的。理论计算表明，带负电的钴介导了电子从镧到吸附态N _2的转移，从而进一步降低了N ₂的活化势垒。 离解。最重要的是，特定的LaCoSi几何构型以强烈的放热效应稳定了N _2的吸附，这大大降低了N ₂活化的表观能垒。因此，LaCoSi示出了优良的活性（1250  μ摩尔克^-1  ħ ^-1）中，用温和的反应条件下（400下一个60倍的增加超过负载的钴催化剂的活性 ° C，0.1兆帕）。