Herein, a self-activated phosphor SrCaGa 4 O 8 with excellent thermal stability was synthesized by high temperature solid state reaction method. It exhibited the broad emission range from 300 to 600 nm under 220 nm excitation, which may be caused by the intrinsic defects of host. Specifically, with the temperature increasing, the photoluminescence (PL) color changed from bluish to yellow-green and the maximum of PL intensity at 550 nm was obtained when reaching 493 K. From thermoluminescence curves and high temperature spectra, it was found that the anti-thermal quenching phenomenon could be dependent on the self-compensation of the carriers. Accordingly, the results of temperature-dependent intensity ratio and sensitivity show that SrCaGa 4 O 8 may have potential in the optical temperature sensing.
Visual optical information encryption–decryption and anti-counterfeiting (IEDAC) technology play a vital role in the field of information security. Recent luminescent information encryption technologies face the disadvantages of depending on external large-scale stimulus decryption equipment, inability to read out repeatedly, and information leakage, impeding the practical applications of luminescence encryption. Here, an integrated luminescent IEDAC chip is proposed, which provides a convenient approach to store and decipher pre-patterned luminescence information based on laser engraved template and film heater. The luminescent encryption chip contains a double-layer structure made up of long persistent phosphors based on SrCaGa 4 O 8 host and a laser induced graphene heater, which makes it possible to decrypt information on a single chip. This design enables dual-mode (photoluminescence/long persistent luminescence), dual-color (blue/yellow-green), and multi-level IEDAC function, providing a novel insight and integrated strategy for implementing advanced IEDAC technologies.
危险品化学品经营许可证（带存储）