ABSTRACT

Single-atom catalysts (SACs) have received boosting attention due to their high atom utilization and incredible activities in a wide range of catalytic processes. Numerous SACs have been investigated for CO oxidation both experimentally and theoretically, including noble-metal catalysts (Pt, Au, Pd, etc.) and non-noble-metal catalysts (Fe, Co, Ni, etc.), in which the atomically dispersed metal atoms are anchored on supports via strong metal-support interactions. This unique structure of SACs contributes to activating the adsorbed CO and O₂ and stabilizing the intermediates. Electron transfer between the metal atom and the support plays an important role in tuning the electronic structure, which can greatly influence the activity, selectivity, and stability of SACs. In this review, the design principles and synthesis methods of SACs for CO oxidation are discussed with emphasis on single-atom active sites and metal-support interactions. Four CO oxidation mechanisms over SACs are evaluated. Moreover, the challenges and future research directions for SAC-catalyzed CO oxidation are outlined.

摘要

单原子催化剂（SAC）由于其高原子利用率和在广泛的催化过程中令人难以置信的活性而受到越来越多的关注。已经在实验和理论上研究了许多用于 CO 氧化的 SAC，包括贵金属催化剂（Pt、Au、Pd 等）和非贵金属催化剂（Fe、Co、Ni 等），其中原子分散的金属原子通过强大的金属-载体相互作用锚定在载体上。SAC 的这种独特结构有助于激活吸附的 CO 和 O ₂并稳定中间体。金属原子和载体之间的电子转移在调整电子结构方面起着重要作用，这会极大地影响 SAC 的活性、选择性和稳定性。在这篇综述中，讨论了用于 CO 氧化的 SACs 的设计原理和合成方法，重点是单原子活性位点和金属-载体相互作用。评估了 SAC 上的四种 CO 氧化机制。此外，概述了 SAC 催化 CO 氧化的挑战和未来研究方向。