Thermometric sensing performance in Erbium modified SrBi2-xNb2ErxO9 ferroelectric ceramic for optoelectronic devices

Abstract

Er3+ doped ferroelectric ceramic compositions SrBi2-xNb2ErxO9 (x = 0–5 mol %) are prepared by solid-state reaction method and sintered at 1000 °C. The ceramic's structural, ferroelectric, optical, and thermometric sensor properties have been studied. The XRD analysis confirmed the orthorhombic geometry and the A21am phase group of the ceramic. The FTIR studies revealed the typical modes (602 cm−1 and 802 cm−1) of the Aurivillius phases of bismuth layered structure ferroelectrics (BLSFs). The improved hysteresis loops are traced under the electric field < ± 50 kV/cm, and P-E parameters seem to be affected by the insertion of the Er3+ dopant. In upconversion luminescence (UCL) spectra, two intense green bands at 529 nm and 549 nm and a diminished red peak at 670 nm have been identified, corresponding to a 980 nm exciting wavelength. The increase in the lifetime with changing erbium content indicates the efficient energy transfer in Er3+ ions, which results in non-radiative transition at a higher doping level. The optimum dopant concentration is x = 0.03 and is used to measure the pump power dependence on the UCL emission intensity. This study suggests that the two photons are involved in green and red UC emissions. The maximum sensitivity achieved in SrBi2-xNb2ErxO9 ceramic at x = 0.03 is 0.0086 K−1 at 443 K, ranging between temperatures 303 K–443 K, making it a promising non-contact sensor material.