Creating dual-mode luminescence in piezoelectric calcium niobates through lanthanide-doped for anti-counterfeiting and temperature sensing

Lanthanide-doped luminescent materials have been widely used in the field of information security and optical sensing, owing to their unique optical properties. However, conventional luminescent materials usually exhibit unicolor and single-peak emission, which leads to a decrease in the application efficiency of anti-counterfeiting and optical temperature sensing. In this work, we have successfully developed a series of novel multi-mode stimulation luminescent materials in the Ca2Nb2O7 system via the solid phase reaction. This luminescent material is synthesized by doping dual lanthanide ions to realize adjustable multi-mode luminescence, which simultaneously create luminescent centers and carrier traps in the host lattice. The multi-colored emission can be realized under different excitation wavelengths. Meanwhile, it has a combination of fluorescent phenomenon by upconversion, down-shifting and thermal stimulation. In addition, the fluorescence intensity ratio of lanthanide ions shows significant temperature dependence, and the maximum Sr is 0.0072 K−1 at 293 K. Hence, we have fabricated a novel material that can be used for multi-mode anti-counterfeiting and optical temperature sensing.