Photoluminescence in Sm3+ activated 0.92(Na0.5Bi0.5)TiO3-0.08(Ba0.90Ca0.10)(Ti0.92Sn0.08)O3 multifunctional lead-free ferroelectric ceramics for non-contact optical thermometry

A series of Sm 3+ doped 0.92(Na 0.5 Bi 0.5 )TiO 3 -0.08(Ba 0.90 Ca 0.10 )(Ti 0.92 Sn 0.08 )O 3 (NBT-8BCTS: x Sm 3+ , x  = 0–0.025) lead-free piezoelectric ceramics are fabricated via a conventional solid-state reaction method, and their phase structure, photoluminescence properties and temperature dependent of luminescence spectra are studied in detail. The emission spectra with dominant orange-red emission consist of four emission peaks at 542 nm, 598 nm, 644 nm and 709 nm, which are ascribed to the 4 G 5/2 → 6 H J/2 (J = 5, 7, 9, 11) transition of Sm 3+ ions, respectively. Furthermore, the optical temperature sensing properties of the NBT-8BCTS: 0.01Sm 3+ ceramic in the temperature range between 313 K and 533 K are analyzed with a maximum relative sensitivity 1.29%K −1 at T  = 463 K. Besides, the phosphors exhibit excellent stable temperature sensing performance under repeated heat-cooling cycles. These results suggest that the Sm 3+ doped NBT-8BCTS ceramics may have potential applications in multifunctional sensing devices by integrating its optical temperature sensing and intrinsic ferroelectric property .