Heterogeneous single-cluster catalysts (SCCs) comprising atomically precise and isolated metal clusters stabilized on appropriately chosen supports offer exciting prospects for enabling novel chemical reactions owing to their broad structural diversity with unparalled opportunities for engineering their properties. Although the pioneering work revealed intriguing performance trends of size-selected metal clusters deposited on supports, synthetic and analytical challenges hindered a thorough understanding of surface chemistry under realistic conditions. This Review underscores the importance of considering the cluster environment in SCCs, encompassing the development of robust metal–support interactions, precise control over the ligand sphere, the influence of reaction media and dynamic behaviour, to uncover new reactivities. Through examples, we illustrate the criticality of tailoring the entire catalytic ensemble in SCCs to achieve stable and selective performance with practically relevant metal coverages. This expansion in application scope transcends from model reactions to complex and technically relevant reactions. Furthermore, we provide a perspective on the opportunities and future directions for SCC design within this rapidly evolving field.

异质单簇催化剂（SCC）由稳定在适当选择的载体上的原子级精确且孤立的金属簇组成，由于其广泛的结构多样性以及无与伦比的设计其性能的机会，为实现新型化学反应提供了令人兴奋的前景。尽管这项开创性的工作揭示了沉积在载体上的选定尺寸的金属簇的有趣的性能趋势，但合成和分析的挑战阻碍了对现实条件下表面化学的透彻理解。本综述强调了考虑 SCC 中簇环境的重要性，包括发展强大的金属-载体相互作用、对配体球的精确控制、反应介质和动态行为的影响，以发现新的反应性。通过示例，我们说明了定制 SCC 中整个催化整体的重要性，以实现稳定和选择性的性能以及实际相关的金属覆盖率。应用范围的扩展超越了模型反应到复杂且技术相关的反应。此外，我们还对 SCC 设计在这个快速发展的领域中的机遇和未来方向提供了展望。