Preparation, luminescence properties, and application of temperature sensing and anti‐counterfeiting of La2MgTiO6:Yb3+/Ln3+/Mn4+

Abstract The doping of transition metal ions in the up‐conversion (UC) luminescent material doped with Yb 3+ /Ln 3+ is a facile way to increase their UC luminescence intensities and alter their colors. In this study, La 2 MgTiO 6 :Yb 3+ /Mn 4+ /Ln 3+ (Ln 3+ = Er 3+ , Ho 3+ , and Tm 3+ ) phosphors showing excellent luminescence properties were prepared by a solid‐state method. The sensitivity of the La 2 MgTiO 6 :Yb 3+ /Ln 3+ /Mn 4+ phosphor was double that without Mn 4+ , because Mn 4+ affects the UC emissions of Ln 3+ via energy transfer between these ions. Moreover, Mn 4+ also acts as a down‐conversion activator, which can combine with UC ions to achieve multi‐mode luminescence at different wavelengths. Under 980 nm excitation, these samples emit green light (from Er 3+ and Ho 3+ ) and blue light (from Tm 3+ ). In contrast, under 365 nm excitation, they emit red light (from Mn 4+ ). Further testing revealed that the La 2 MgTiO 6 :Yb 3+ /Mn 4+ /Ln 3+ phosphors have potential applications in temperature sensing and anti‐counterfeiting.