Abstract
High-temperature afterglow organic amorphous materials expand the operational temperature beyond traditional room-temperature phosphorescent materials, broadening their potential applications. However, achieving tunable high-temperature afterglow from a single luminescent molecule remains a formidable challenge. Here, we employ host-guest anchoring coupled with single-bond rotors to achieve effective phosphorescence and tunable afterglow at high temperature simultaneously. The material demonstrates a wavelength-tunable afterglow: during heating (298 K to 473 K), the chromaticity coordinate shifts from (0.24, 0.47) to (0.18, 0.20) and the lifetime from 836 ms to 6.34 ms. The theoretical investigations reveal that the excited-state conformation of phosphors undergoes a temperature-dependent transformation, inducing the wavelength-tunable high-temperature afterglow phenomenon. This work offers a strategy for designing tunable high-temperature afterglow-emitting amorphous polymers, advancing the development of organic phosphorescent materials capable of delivering tunable high-temperature afterglow emissions.