Abstract: As a pivotal class of high-performance catalysts, metal clusters (MCs) play a significant role in catalytic applications owing to their unique electronic structures and quantum size effects. However, during synthesis and catalytic processes, MCs tend to aggregate due to their inherent high surface energy, leading to increased particle size, reduced active sites, and surface reconstruction, which collectively diminish their catalytic activity and selectivity. Recent studies have employed porous organic cages (POCs)—a category of porous materials with permanent cavity structures—to mitigate MC aggregation and enhance catalytic performance. POCs provide an ideal confined microenvironment for MCs, enabling precise structural control while preserving catalytic activity. This review adopts an anthropomorphic narrative approach to systematically outline POC-based confinement strategies for MCs and discusses recent advances in MC-POC hybrid systems for catalytic applications, aiming to foster reader engagement and understanding of these encapsulation methodologies.

Key words: Metal cluster, Porous organic cage, Encapsulation strategy, Confined catalysis