Supramolecular Multivalent Synergy Enabling Harsh‐Condition Phosphorescence

Organic phosphorescence, which arises from the radiative decay of triplet excitons, has garnered significant interest owing to its exceptional photophysical properties and diverse application potential. However, the intrinsically vulnerable triplet excitons are highly susceptible to environmental factors such as heat, oxygen, and solvents, which significantly compromise the operational stability and durability of organic phosphorescent materials (OPMs). The triplet excitons undergo rapid deactivation via thermal dissipation, oxygen-mediated energy transfer, and solvent-induced collapse of rigid microenvironments, leading to severe phosphorescence quenching. Supramolecular multivalent synergy offers an effective strategy for stabilizing triplet excitons, thereby extending beyond ambient stability to sustained phosphorescence under harsh conditions, resulting in robust organic harsh-condition phosphorescence (HCP) materials. This review provides a timely and systematic introduction to recent advances in HCP materials, including design and construction strategies, unique optoelectronic properties, underlying stabilization mechanisms, and promising applications. In addition, the summary section highlights pivotal challenges and emerging perspectives within this field to suggest feasible pathways for future research endeavors. This review not only establishes design principles for HCP materials by decoding supramolecular multivalent synergy in triplet exciton stabilization but also paves new avenues toward practical applications.