Zhang Jingjing, Zhang Yifei, Qin Zhaoxian, Li Zhiwen, Tong Zhaohui, Zhao Zhen, Gascón José A, Li Gao
State Key Laboratory of Catalysis, Dalian Institute of Chemical Physics, Chinese Academy of Sciences, Dalian, 116023, China.
University of Chinese Academy of Sciences, Beijing, University of, 100049, China, China.
Angew Chem Int Ed Engl. 2025 Mar 3;64(10):e202420993. doi: 10.1002/anie.202420993. Epub 2024 Dec 4.
Metal nanoclusters stabilized by N-heterocyclic carbene (NHC) ligands have attracted increasing interest for their special structures and diverse applications. However, developing synthetic strategies and extending the database of NHC-protected nanoclusters are still challenging tasks. In this work, a novel and rapid synthetic method is developed to prepare AuAg alloy nanocluster ligated by carbene based on the reactivity of nanoclusters. The rod-like carbene-capped bimetal nanocluster, [AuAg(PPh)(BMIm)I]SbF (AuAg : BMIm), was achieved and characterized by a series of techniques. The alloy nanocluster consists of two vertex-sharing icosahedrons and carbene ligands, phosphine ligands, and I atoms. Interestingly, the introduced carbene ligands show strong coordination capabilities with Au, enhancing the interaction between metal core and ligands. To the best of our knowledge, the carbene-capped AuAg : BMIm nanocluster is the first of its kind to show higher thermostability and higher sensitivity to light compared with the homogeneously capped analogue nanocluster ([AuAg(PPh)I]SbF). Density functional theory calculations attribute these properties to a unique delocalization of electrons within the frontier orbitals. Finally, the AuAg : BMIm anchored on NiFe-LDH exhibits remarkable electrocatalytic activity in the electrosynthesis of urea from NO and CO, achieving a urea production rate of 29.5 mmol g h with a Faradaic efficiency of 34 % at -0.5 V (vs. RHE).
由氮杂环卡宾（NHC）配体稳定的金属纳米团簇因其特殊结构和多样应用而受到越来越多的关注。然而，开发合成策略并扩展NHC保护的纳米团簇数据库仍然是具有挑战性的任务。在这项工作中，基于纳米团簇的反应性，开发了一种新颖且快速的合成方法来制备由卡宾连接的AuAg合金纳米团簇。获得了棒状卡宾封端的双金属纳米团簇[AuAg(PPh)(BMIm)I]SbF（AuAg : BMIm），并通过一系列技术对其进行了表征。该合金纳米团簇由两个顶点共享的二十面体以及卡宾配体、膦配体和I原子组成。有趣的是，引入的卡宾配体与Au表现出很强的配位能力，增强了金属核与配体之间的相互作用。据我们所知，与均相封端的类似纳米团簇（[AuAg(PPh)I]SbF）相比，卡宾封端的AuAg : BMIm纳米团簇是首个表现出更高热稳定性和更高光敏感性的此类纳米团簇。密度泛函理论计算将这些性质归因于前沿轨道内电子的独特离域。最后，锚定在NiFe-LDH上的AuAg : BMIm在由NO和CO电合成尿素中表现出显著的电催化活性，在-0.5 V（相对于可逆氢电极）下实现了29.5 mmol g h的尿素产率，法拉第效率为34 %。
