Open Access Research Article Issue
Improved piezoelectric and luminescent properties in Sm-modified Bi0.5Na0.5TiO3-BaTiO3 multifunctional ceramics
Journal of Materiomics 2024, 10 (4): 803-810
Published: 18 October 2023
Abstract Collect

The 0.93(Na0.5Bi0.5)1-xSmxTiO3-0.07BaTiO3 multifunctional ceramics were prepared by solid-phase reaction method. The phase structure, microstructure, electrical and photoluminescent properties were systematically studied. With increasing x, the ceramics undergoes the phase transition from rhombohedral to tetragonal with some rhombohedral distortion, along with a reduced grain size and increased relative density. On the other hand, the Sm3+ doping enhances the electric-field driven reversible phase transition and domain size, and reduces the domain walls, thereby contributing to improved piezoelectricity and decreased depolarization temperature (Td) from 91 ℃ to 40 ℃. Excellent piezoelectric properties of d33 = 213 pC/N and kp = 29.9% are achieved in the x = 0.010 ceramic. Under excitation (407 nm), the Sm3+-doped ceramic exhibits bright reddish-orange fluorescence at 564, 599, 646 nm and 710 nm. A polarization-induced enhancement of photoluminescence is obtained in BNBT-xSm ceramics with an improved relative intensity of emission band at 646 nm. These results indicate that Sm3+-doped BNBT ceramics show great potential in electro-optic integration and coupling device applications.

Open Access Research Article Issue
Photocurrent density and electrical properties of Bi0.5Na0.5TiO3-BaNi0.5Nb0.5O3 ceramics
Journal of Advanced Ceramics 2021, 10 (5): 1119-1128
Published: 19 July 2021
Abstract PDF (13.5 MB) Collect

In this work, the (1-x)Bi0.5Na0.5TiO3-xBaNi0.5Nb0.5O3 (BNT-BNN; 0.00 ≤ x ≤ 0.20) ceramics were prepared via a high-temperature solid-state method. The crystalline structures, photovoltaic effect, and electrical properties of the ceramics were investigated. According to X-ray diffraction, the system shows a single perovskite structure. The samples show the normal ferroelectric loops. With the increase of BNN content, the remnant polarization (Pr) and coercive field (Ec) decrease gradually. The optical band gap of the samples narrows from 3.10 to 2.27 eV. The conductive species of grains and grain boundaries in the ceramics are ascribed to the double ionized oxygen vacancies. The open-circuit voltage (Voc) of ~15.7 V and short-circuit current (Jsc) of ~1450 nA/cm2 are obtained in the 0.95BNT-0.05BNN ceramic under 1 sun illumination (AM1.5G, 100 mW/cm2). A larger Voc of 23 V and a higher Jsc of 5500 nA/cm2 are achieved at the poling field of 60 kV/cm under the same light conditions. The study shows this system has great application prospects in the photovoltaic field.

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