Electrocatalytic dinitrogen reduction reaction (N₂RR) is an emerging route for ammonia synthesis at ambient conditions. Albeit the “π back-donation” process enables N₂RR activity on transition metals with empty d-orbitals, given its dilemma in overcoming hydrogen evolution reaction (HER) competition, exploring p-block-element-based catalysts with relatively inferior HER activity is achievable for high selectivity. The challenge lies in designing rational structure to improve N₂RR activity. Here, we synergistically integrate oxygen vacancy (V_O) with hydroxyl on Bi₄O₅I₂ (V_O-Bi₄O₅I₂-OH), which render this p-block-element-based material active to mimic “π back-donation” behavior because of sufficient vacant orbitals. In neutral media, the electrocatalytic N₂RR performance of V_O-Bi₄O₅I₂-OH in terms of splendid faradic efficiency (32.4%) is superior to most of the prior reports using p-block-element-based catalysts. Our findings show a new strategy toward standout N₂RR activity, which holds great potential in exploiting other p-block-element-based electrocatalysts.

电催化二氮还原反应（N ₂ RR）是在环境条件下合成氨的新兴途径。尽管“π背向供体”过程能够使具有空d轨道的过渡金属具有N ₂ RR活性，但由于其在克服氢释放反应（HER）竞争方面的困境，探索了具有相对较低HER活性的基于p嵌段元素的催化剂可实现高选择性。挑战在于设计合理的结构以改善N ₂ RR活性。在这里，我们协同整合氧空位（V _ø与羟基上Bi）的₄ ø ₅我₂（V _ø -Bi ₄ ö₅ I ₂ -OH），由于足够的空轨道，使这种基于p嵌段元素的材料具有活性，可模仿“π背向捐赠”行为。在中性介质中，电催化Ñ ₂的RR性能V _ø -Bi ₄ ø ₅我₂ -OH在灿烂法拉第效率（32.4％）是优于大多数的使用基于p区元素的催化剂与现有的报告条件。我们的发现表明，N ₂ RR活性非常出色，这在开发其他基于p嵌段元素的电催化剂方面具有巨大潜力。