Recent advances in room-temperature phosphorescence metal–organic frameworks: structural design, property modulation, and emerging applications

Abstract

Room-temperature phosphorescence (RTP) has attractive features of large Stokes shifts, long-lived emission, and diverse excited-state manifolds, yet its advancement is limited by the stringent requirements of efficient generation and robust stabilization of triplet excitons. Metal–organic frameworks (MOFs) present a particularly elegant platform to overcome this limitation: metal nodes/clusters act as internal heavy atoms to enhance spin–orbit coupling, thereby promoting intersystem crossing, while the rigid, porous architecture of the MOFs facilitates the immobilization of phosphors to suppress non-radiative decay and enables the construction of a protective microenvironment that excludes molecular oxygen. This review provides a timely and systematic overview of the advances in MOF-based RTP systems over the past three years. We categorize the structural design strategies into two archetypes: phosphorescent ligands as structural motifs and a host–guest approach. A detailed discussion further elucidates how metal-node species, ligand engineering, guest/solvent environments, and external stimulus modulate the RTP performance. Emerging applications in solid-state lighting, chemical sensing, anti-counterfeiting, and high-security information encryption are also examined. Finally, current challenges and future directions are outlined to guide the rational design of high-performance MOF-based RTP materials.