School of Chemical Engineering & Technology, Key Laboratory for Green Chemical Technology of Ministry of Education, Tianjin University, Tianjin, China.
Collaborative Innovation Center for Chemical Science & Engineering (Tianjin), Tianjin, China.
Nat Nanotechnol. 2023 Jun;18(6):611-616. doi: 10.1038/s41565-023-01344-z. Epub 2023 Mar 27.
Geometrically isolated metal atoms in alloy catalysts can target efficient and selective catalysis. However, the geometric and electronic disturbance between the active atom and its neighbouring atoms, that is, diverse microenvironments, makes the active site ambiguous. Herein, we demonstrate a methodology to describe the microenvironment and determine the effectiveness of active sites in single-site alloys. A simple descriptor, degree-of-isolation, is proposed, considering both electronic regulation and geometric modulation within a PtM ensemble (M = transition metal). The catalytic performance of PtM single-site alloy is examined thoroughly using this descriptor for an industrially important reaction, propane dehydrogenation. The volcano-shaped isolation-selectivity plot reveals a Sabatier-type principle for designing selective single-site alloys. Specifically, for a single-site alloy with a high degree-of-isolation, alternation of the active centre has a great impact on tuning selectivity, validated by the outstanding consistency between experimental propylene selectivity and the computational descriptor.
合金催化剂中几何隔离的金属原子可以实现高效和选择性催化。然而，活性原子与其相邻原子之间的几何和电子干扰，即多样化的微环境，使得活性位不明确。在本文中，我们提出了一种描述微环境和确定单原子合金中活性位有效性的方法。提出了一个简单的描述符，即离度，同时考虑了 PtM 整体（M=过渡金属）中的电子调节和几何调制。利用该描述符对工业上重要的丙烷脱氢反应进行了深入研究，考察了 PtM 单原子合金的催化性能。离度选择性火山图揭示了设计选择性单原子合金的 Sabatier 型原理。具体来说，对于具有高离度的单原子合金，活性中心的交替对调对调选择性有很大影响，实验丙烯选择性与计算描述符之间的出色一致性验证了这一点。
