ABSTRACT The escalating global energy crisis has intensified the demand for advanced materials that enable efficient energy storage and conversion. Porous organic cages (POCs), together with their metal cluster (MC) composites, have recently emerged as a versatile and powerful class of functional materials for energy‐related applications. POCs combine discrete, shape‐persistent molecular architectures with intrinsic porosity, structural modularity, and solution processability, while MCs impart well‐defined electronic, catalytic, and redox‐active properties. The integration of these two components creates hybrids that synergistically unite molecular precision with functional complexity. This Review presents a comprehensive overview of the synthetic strategies used to construct POCs and POC‐MC composites, with particular emphasis on rational design principles that link synthetic choices to targeted energy applications. We highlight recent advances in tailoring cage structures, cavity environments, and host‐guest interactions to regulate the dispersion, stability, and reactivity of MCs. The resulting materials have demonstrated broad utility across diverse energy technologies, including thermocatalysis, photocatalysis, electrocatalysis, energy harvesting, rechargeable battery systems such as lithium‐ion, perovskite solar, and aqueous zinc batteries, as well as proton‐conducting materials. Finally, we critically assess the key achievements, unresolved challenges, and future opportunities in translating POC‐based materials from fundamental studies toward practical energy storage and conversion technologies.
Yu et al. (2026) studied this question.