Optimization of inorganic rare-earth afterglow materials and their optoelectronic applications

Inorganic rare-earth afterglow materials can emit light continuously after the removal of external excitation, making them attractive for optoelectronic applications including low-power displays, visual signaling, and plant light regulation. Their performance arises from the coupled effects of the host lattice, rare-earth ion energy levels, trap state distributions, and composite structures rather than relying solely on the luminescent centers themselves. In recent years, host-emitter energy-level matching, defect engineering, and composite-structure optimization have significantly improved the emission range, afterglow lifetime, and environmental stability of these materials. This review outlines the composition of rare-earth afterglow materials and the fundamental afterglow process, then summarizes recent advances in emission-band regulation, carrier storage and release, and structural optimization. Representative applications in lighting and display devices, transportation and outdoor signage, plant light regulation and smart agriculture are discussed. Finally, key challenges are highlighted, including the scarcity of efficient red and near-infrared afterglow systems, the difficulty of quantitatively characterizing trap structures, and the need for improved long-term stability and device integration. This review aims to clarify structure-property-function relationships in rare-earth afterglow materials and provide guidance for the development and implementation of high-performance afterglow systems.