Single-atom catalysts (SACs) have emerged as a new class of materials for the development of active and selective catalysts. These materials are commonly based on anchoring a noble transition metal to some kind of carrier. In the present work, we demonstrate that MXenes─two-dimensional materials with application in energy storage and conversion─spontaneously form SAC-like sites under anodic polarization conditions, using the applied electrode potential as a probe to form catalytically active surface sites reminiscent of a SAC-like structure. Combining ab initio molecular dynamics simulations and electronic structure calculations in the density functional theory framework, we demonstrate that only the SAC-like sites rather than the basal planes of MXenes are highly active and selective for the oxygen evolution or chlorine evolution reactions, respectively. Our findings may simplify synthetic routes toward the formation of active and selective SAC-like sites and could pave the way for the development of smart materials by incorporating fundamental principles from nature into material discovery: while the pristine form of the material is inactive, the application of an electrode potential activates the material by the formation of active and selective single-atom centers.

中文翻译：

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MXenes 在阳极极化条件下自发形成活性和选择性单原子中心


单原子催化剂 （SAC） 已成为一类用于开发活性和选择性催化剂的新型材料。这些材料通常基于将贵金属过渡金属锚定到某种载体上。在本工作中，我们证明了 MXenes（应用于储能和转换的二维材料）在阳极极化条件下自发形成类似 SAC 的位点，使用施加的电极电位作为探针形成催化活性表面位点，让人想起 SAC 样结构。结合密度泛函理论框架中的从头分子动力学模拟和电子结构计算，我们证明了只有 SAC 样位点而不是 MXenes 的基平面分别对析氧或析氯反应具有高活性和选择性。我们的研究结果可能会简化形成活性和选择性 SAC 样位点的合成途径，并通过将自然界的基本原理融入材料发现中，为智能材料的开发铺平道路：虽然材料的原始形式是无活性的，但电极电位的应用通过形成活性和选择性单原子中心来激活材料。