加州大学洛杉矶化学与生物化学Ning Yan研究团队发现用电喷雾质谱观察反应中的单原子催化位点方法。 相关论文于2020年11月18日发表于国际顶尖学术期刊《德国应用化学》。

单原子催化剂（SACs）已成为多相催化领域的一个突出方向，这不仅仅是因为它对活性位点有着潜在的基本洞察能力。然而，由于大多数可用SACs的不均匀性以及缺乏原子分辨率结构的结构-活性相关性研究工具，因此无法达到期望的理解水平。

该文中，研究人员描述了电喷雾质谱（ESI-MS）在多金属氧酸盐催化反应中研究分子态SACs的潜力。研究人员能够确定在液相中CO和酒精氧化反应中活性位点的确切组成及其在催化循环中的演变。获得了有关金属依赖的反应机理、关键中间体、活性位点动力学甚至逐步激活屏障的关键信息。通过普遍采用的研究SAC的技术很难收集到这些信息。DFT计算揭示了反应机理的复杂细节，ESI-MS定义的SAC位点和电子结构理论计算之间的强大协同作用变得明显。

附：英文原文

Title: Observing single‐atom catalytic sites during reactions with electrospray ionisation mass spectrometry

Author: Max J. Hü, Geng Sun, Philippe Sautet, Ning Yan

Issue&Volume: November 18, 2020

Abstract: Single‐atom catalysts (SACs) have become a prominent theme in heterogeneous catalysis, not least because of the potential fundamental insight into active sites. The desired level of understanding, however, is prohibited due to the inhomogeneity of most supported SACs and the lack of suitable tools for structure‐activity correlation studies with atomic resolution. Herein, we describe the potency of electrospray ionisation mass spectrometry (ESI‐MS) to study molecularly defined SACs supported on polyoxometalates in catalytic reactions. We were able to identify the exact composition of active sites and their evolution in the catalytic cycle during CO and alcohol oxidation reactions performed in the liquid phase. Critical information on metal‐dependent reaction mechanisms, the key intermediates, the dynamics of active sites and even the stepwise activation barriers were obtained, which would be challenging to gather via prevailingly adopted techniques in SAC research. DFT calculations revealed intricate details of the reaction mechanisms, and strong synergies between ESI‐MS defined SAC sites and electronic structure theory calculations become apparent.

DOI: 10.1002/anie.202011632

Source: https://onlinelibrary.wiley.com/doi/10.1002/anie.202011632