德国哥廷根大学Alec M. Wodtke研究团队经过不懈努力，观察了钯上的协同吸附结合催化高温氢氧化。2024年11月1日出版的《科学》杂志发表了这项成果。

通过多相催化剂加速反应活性的原子尺度结构，通常只在高温高压的反应条件下形成，这使得它们不能用低温、超高真空的方法观察到。

有鉴于此，研究小组提出了在广泛的表面浓度和高温下，钯催化氢氧化的速度分辨动力学测量。速率表现出对氧覆盖和步骤密度的复杂依赖，这可以用密度泛函和基于过渡态理论的动力学模型来定量解释，该模型涉及至少三个氧原子在步骤中的协同稳定构型。

两个氧原子将第三个氧原子吸引到附近的结合位点，从而产生比孤立氧原子活性强得多的活性结构。因此，钯上的氢氧化为如何在工作催化剂上增强反应性，提供了一个清晰的例子。

附：英文原文

Title: Cooperative adsorbate binding catalyzes high-temperature hydrogen oxidation on palladium

Author: Michael Schwarzer, Dmitriy Borodin, Yingqi Wang, Jan Fingerhut, Theofanis N. Kitsopoulos, Daniel J. Auerbach, Hua Guo, Alec M. Wodtke

Issue&Volume: 2024-11-01

Abstract: Atomic-scale structures that account for the acceleration of reactivity by heterogeneous catalysts often form only under reaction conditions of high temperatures and pressures, making them impossible to observe with low-temperature, ultra-high-vacuum methods. We present velocity-resolved kinetics measurements for catalytic hydrogen oxidation on palladium over a wide range of surface concentrations and at high temperatures. The rates exhibit a complex dependence on oxygen coverage and step density, which can be quantitatively explained by a density functional and transition-state theory–based kinetic model involving a cooperatively stabilized configuration of at least three oxygen atoms at steps. Here, two oxygen atoms recruit a third oxygen atom to a nearby binding site to produce an active configuration that is far more reactive than isolated oxygen atoms. Thus, hydrogen oxidation on palladium provides a clear example of how reactivity can be enhanced on a working catalyst.

DOI: adk1334

Source: https://www.science.org/doi/10.1126/science.adk1334