LAUSR

Abstract The deep-red multifunctional Mg2TiO4:Mn4+ phosphor was synthesized for photoluminescence (PL), thermometry, and latent fingerprint visualization applications. Phosphors synthesized using a solid-state reaction (SSR) were composed of a binary phase consisting of 67.4% Mg2TiO4 and 32.6% MgTiO3. In addition, a single-phase Mg2TiO4 phosphor was prepared using a citric-acid-assisted sol-gel process, which exhibited a 2.24-fold PL enhancement compared to the phosphor prepared by SSR. Thermometry analysis revealed a linear relationship between PL intensity (I) and temperature (T) within the range of 293–393 K: T = −142.8I + 432.4. The absolute and relative sensitivities were determined to be 7.0 × 10−3 and 25.4 × 10−3 K−1, respectively, at 393 K. Furthermore, the Mg2TiO4:Mn4+ phosphor was shown to be capable of visualizing latent fingerprints and identified level 1 and 2 features well. We demonstrated that Mg2TiO4:Mn4+ is a multifunctional phosphor that is suitable for use in PL, thermometry, and latent fingerprint visualization applications.