Enhanced electrical properties, color-tunable up-conversion luminescence, and temperature sensing behaviour in Er-doped Bi3Ti1.5W0.5O9 multifunctional ferroelectric ceramics

Er-doped Bi3Ti1.5W0.5O9 (BTW-x) ferroelectric ceramics were prepared by a conventional solid-state reaction synthesis method, and their structure, electrical properties, up-conversion (UC) luminescence, and temperature sensing behaviour were investigated. A high piezoelectric coefficient d(33) (9.6 pC/N), a large remnant polarization P-r (12.75 mu C/cm(2)), a high Curie temperature Tc (730.2 degrees C), and the optimal luminescent intensity are obtained for the samples at x = 0.05. By changing the Er doped concentration, the BTW-x ceramics are capable of generating various UC spectra and the color could be tunable from green to yellow. According to the fluorescence intensity ratio of green emissions at 532.6 nm and 549.2 nm in the temperature range from 83K to 423 K, optical temperature sensing properties are investigated and the maximum sensing sensitivity is found to be 0.00314K(-1) at 423 K. The results conclude that BTW-x would be a candidate in high temperature sensor, fluorescence thermometry, and opto-electronic integration applications. Published by AIP Publishing.