Abstract：
The electrocatalytic reduction reaction of nitrate (NO3 -) to ammonia (NH3) is a feasible way to achieve artificial nitrogen cycle. However, the low yield rate and poor selectivity toward NH3 product is a technical challenge. Here a graphdiyne (GDY)-based tandem catalyst featuring Cu/CuxO nanoparticles anchored to GDY support (termed Cu/CuxO/GDY) for efficient electrocatalytic NO3 - reduction is presented. A high NH3 yield rate of 25.4 mg h-1 mgcat. -1 (25.4 mg h-1 cm-2) with a Faradaic efficiency of 99.8% at an applied potential of -0.8 V versus RHE using the designed catalyst is achieved. These performance metrics outperform most reported NO3 - to NH3 catalysts in the alkaline media. Electrochemical measurements and density functional theory reveal that the NO3 - preferentially attacks Cu/CuxO, and the GDY can effectively catalyze the reduction of NO2 - to NH3. This work highlights the efficacy of GDY as a new class of tandem catalysts for the artificial nitrogen cycle and provides powerful guidelines for the design of tandem electrocatalysts.
摘要：
硝酸盐(NO3-)到氨(NH3)的电催化还原反应是实现人工氮气循环的可行途径。然而,低收率和对NH3产物的差的选择性是技术挑战。在这里，我们提出了一种基于石墨炔（GDY）的串联催化剂，其特征是Cu/CuxO纳米颗粒锚定在GDY载体上（称为Cu/CuxO/GDY），用于有效的电催化NO3还原。我们实现了25.4mgh-1mgcat的高NH3产率。-1（25.4mgh-1cm-2），在使用设计的催化剂相对于RHE的-0.8V的施加电位下，法拉第效率为99.8％。这些性能指标优于碱性介质中大多数报道的NO3-至NH3催化剂。电化学测量和密度泛函理论表明，NO3-优先攻击Cu/CuxO，GDY能有效催化NO2-还原为NH3。这项工作突出了GDY作为人工氮循环的新型串联催化剂的功效，并为串联电催化剂的设计提供了有力的指导。本文受版权保护。保留所有权利。
