Single-atom alloys (SAAs) play an increasingly significant role in the field of single-site catalysis and are typically composed of catalytically active elements atomically dispersed in more inert and catalytically selective host metals. SAAs have been shown to catalyze a range of industrially important reactions in electro-, photo-, and thermal catalysis studies. Due to the unique geometry of SAAs, the location of the transition state and the binding site of reaction intermediates are often decoupled, which can enable both facile dissociation of reactants and weak binding of intermediates, two key factors for efficient and selective catalysis. Often, this results in deviations from transition metal scaling relationships that limit conventional catalysts. SAAs also offer reduced susceptibility to CO poisoning, cost savings from reduced precious metal usage, opportunities for bifunctional mechanisms via spillover, and higher resistance to deactivation by coking that plagues many industrial catalysts. In this review, we begin by introducing SAAs and describe how model systems and nanoparticle catalysts can be prepared and characterized. We then review all available SAA literature on a per reaction basis before concluding with a description of the general properties of this new class of heterogeneous catalysts and presenting opportunities for future research and development.

中文翻译：

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单原子合金催化。

单原子合金（SAA）在单中心催化领域中发挥着越来越重要的作用，通常由原子上分散在惰性和催化选择性主体金属中的催化活性元素组成。在电催化，光催化和热催化研究中，SAA已被证明可催化一系列重要的工业反应。由于SAA的独特几何形状，过渡状态的位置与反应中间体的结合位点通常是分离的，这可以使反应物易于解离和中间体的弱结合，这是有效和选择性催化的两个关键因素。通常，这导致偏离过渡金属结垢关系，从而限制了常规催化剂。SAA还降低了对CO中毒的敏感性，由于减少了贵金属的使用，通过溢出产生双功能机理的机会，以及因焦化而使许多工业催化剂困扰的更高的抗失活性，从而节省了成本。在这篇综述中，我们从介绍SAA开始，并描述如何制备和表征模型系统和纳米颗粒催化剂。然后，我们将在每个反应的基础上回顾所有可用的SAA文献，然后对这种新型多相催化剂的一般性质进行描述，并为将来的研究和开发提供机会。我们首先介绍SAA，并介绍如何制备和表征模型系统和纳米颗粒催化剂。然后，我们将在每个反应的基础上回顾所有可用的SAA文献，然后对这种新型多相催化剂的一般性质进行描述，并为将来的研究和开发提供机会。我们首先介绍SAA，并介绍如何制备和表征模型系统和纳米颗粒催化剂。然后，我们将在每个反应的基础上回顾所有可用的SAA文献，然后对这种新型多相催化剂的一般性质进行描述，并为将来的研究和开发提供机会。