Dual-mode luminescence tuning of Er3+ doped Zinc Sulfide piezoelectric microcrystals for multi-dimensional anti-counterfeiting and temperature sensing

In this study, a multi-color and multi-mode luminescence material has been developed for anti-counterfeiting and temperature sensing. The rare earth ions Er3+ are selected as the luminescent center to be doped in the piezoelectric material ZnS. The prepared samples can generate multi-color (orange-yellow-green) and multi-mode (upconversion/down-shifting/energy transfer) emission through the energy transitions of lanthanide ions in the ZnS host. When the excitation wavelength or the temperature is selected to be different, the luminous color is obviously different due to different mode emission. Therefore, multiple anti-counterfeiting of a single compound can be realized, the security degree of the anti-counterfeiting can be improved and overcome the defect of the general fluorescent material in a single light-emitting mode. The work will establish experimental basis for the design and development of a new high-integration functional luminescence material, and is expected to use the developed materials in the fields of optical anti-counterfeiting and information encryption.