氨對於大自然與人類都是十分重要的物質，被廣泛運用於工業、農業與醫學領域。而在儲能方面，由於具有高能量密度及碳中和等特性，也被視為十分具有潛力的物質；然而，工業上傳統的哈伯法製氨需要在嚴峻的環境下進行，還須使用石化燃料作為反應物，過程中會伴隨大量的溫室氣體產生，造成環境上的污染，因此本研究以電催化的方式進行亞硝酸鹽的還原。本研究以金屬有機框架所衍伸的含氮多孔碳材，並使鉬、釕雙金屬以單原子的形式分布其中作為電催化劑，並在中性電解液中進行亞硝酸鹽的還原反應。從實驗結果可知，Mo_SA/NC與Ru_SA/NC在電位 -0.4 V時皆具有最高的法拉第效率，分別是82.36%與78.01%，但兩者的產率卻只有36.63和 29.04 µmol h−1 mg−1；而含有兩種金屬的MoRu_SA/NC在同樣電位的法拉第效率則可上升至90.85%，且氨的產率可以達到60 µmol h−1 mg−1；此外當電位上升至-0.7 V，產率則能達到146.61 µmol h−1 mg−1；其中可以看到每種樣品都有不錯的最大法拉第效率，但雙重金屬單原子的結構卻能讓氨產率又提升了許多，其原因為雙重金屬單原子的結構擁有特殊的配位環境以及相鄰的活化位點，除了能使材料能有更好的電性，也能避免其他副反應的發生，因此能提升法拉第效率與氨產率。

Ammonia (NH3) is such an important substance for both humans and nature, which is widely used in industry, agriculture and medical domain. In terms of energy storage, it is also regarded as a material with great potential due to its high energy density and carbon neutrality. However, the traditional Haber process for ammonia production needs to be carried out under harsh conditions, and must use petrochemical fuels as reactants. The process will be accompanied by releasing large amount of greenhouse gases, which makes environmental pollution even serious. Therefore, this study will use electrocatalyst to reduce nitrite.
In this study, we demonstrate that Mo, Ru dual atom sites（MoRu_SA/NC）serves as nitrite reduction reaction electrocatalysts in neutral electrolytes. Mo_SA/NC and Ru_SA/NC exhibits Faraday efficiency of 82.36% and 78.01% at -0.4 V versus RHE, while the NH3 yield rate is only 36.63 and 29.04 µmol h−1 mg−1, respectively. At the same potential, the FE and the NH3 yield rate of MoRu_SA/NC can be increased to 90.85% and 60 µmol h−1 mg−1. The yield rate will climb to 146.61 µmol h−1 mg−1 with the potential increased to -0.7 V versus RHE. The dual metal sites significantly enhance the production rate, which is attributed to its special coordinate environment and neighbor active sites so that the electrical property will be better. Additionally, side reactions and by products can be inhibited. As a result, Mo, Ru dual atom sites achieve a boosted nitrite reduction reaction performance compared to Mo_SA/NC and Ru_SA/NC.

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