Dy3+ doped (K,Na)NbO3-based multifunctional ceramics for achieving enhanced temperature-stable piezoelectricity and non-contact optical temperature sensing performance

There exists a huge demand for multifunctional materials to keep pace with the development of the next generation of modern electronics featured with high integration, good reliability and multifunction. Herein, we present a novel Dy3+ doped KNN-based lead-free multifunctional fluorescent ferroelectric ceramics. The phase structure, microstructure, electric property and luminescence performance of the Dy3+ KNN-based ceramics were systematically investigated. Through modulating diffused phase transition behavior and mediating unit cell distortion via controlling the contents of Dy dopants, an appreciable and thermally stable d(33) with a minor variation (345 pC N-1 +/- 10%) from 20 to 80 degrees C was obtained in the ceramics. Besides, a considerable d(33)* exceeding 550 pm V-1 was also observed. Most intriguingly, the Dy3+ modified KNN-based ceramics exhibited efficient luminescence, which could be utilized in non-contact optical low-temperature sensing with a maximum relative sensitivity of 5.49% K-1. Given the good and thermally stable piezoelectricity as well as the unique temperature sensing performance, the Dy3+ modified KNN-based ceramics should be a promising material in optoelectronic multifunctional devices.