APPLIED PHYSICS A-MATERIALS SCIENCE & PROCESSING
·
2024
·Vol. 130
·期 12
·1-9
·
IF 2.5
Chen Fei,Ji Cong,Chen Gang,Zhou Zhijun,Su Zhentang,Cai Wei,Gao Rongli,Fu Chunlin
(1- x )NBT- x BY( x = 0.00-0.04) ferroelectric ceramics were fabricated by a solid-state reaction method, and the crystal structure, surface morphology, dielectric, ferroelectric and energy storage properties of NBT ceramics incorporated BY were investigated in detail. Introduction of BY can transformed the phase of NBT from rhombohedral phase R3c to pseudo-cubic phase Pm3m, and make the diffraction peak shift to a lower angle with increasing BY content. Incorporating BY into NBT matrix contributes to the grain refinement for NBT ceramic, and enhances the relaxation performance to a certain extent. The largest dispersion coefficient is obtained when BY content is 0.02. In addition, the dielectric constant decreases with incorporating BY. The introduction of BY into NBT can greatly increase E b , △ P , W rec , and η , as well as a small decrease in P max . When x = 0.010, the relative best energy storage performance is obtained, W rec = 2.07 J/cm 3 , η = 31.66%, which is 10 times and 8 times higher than that of pure NBT ceramics, respectively. This work provides a strategy to strengthen the relaxation behavior and enhance the energy storage performance of ferroelectrics. These findings suggest that the instruction of BY into NBT is an effective method to improve the energy storage properties of NBT ceramic.
研究领域:
材料科学
·
电子工程
✓ 已验证
DOI
高影响因子
Journal of Materials Chemistry C
·
2020
·Vol. 9
·期 4
·1353-1361
·
IF 7.059
Yuzhen Wang,Yanan Wang,Chaoyang Ma,Zhe Feng,Chuandong Zuo,Wanggui Ye,Chong Zhao,Yanbin Li,Zicheng Wen,Zhiquan Cao,Zhijun Cao,Xiaofei Shen,Chong Wang,Yingkui Li,Xuanyi Yuan,Yongge Cao
In this study, various Na0.5Bi0.5TiO3:0.5 at% Ho3+ (NBT:Ho) ceramics with different Yb3+ ion doping concentrations were synthesized by a conventional solid-state reaction method. Under the irradiation of a 980 nm laser, the NBT:Ho sample exhibited four distinguished emission bands centered at 525, 548, 656, and 753 nm. By co-doping Yb3+ ions into NBT as the sensitizers, the up-conversion luminescence of Ho3+ ions was greatly enhanced. The mechanism for up-conversion luminescence was determined to be a two-photon absorption process. The DFT simulations revealed that the Ho3+ 4f orbitals pass through the Fermi level and thus f–f transitions could be highly sensitive to temperature variation. Green emissions at 525 and 548 nm were ascribed to the two thermally coupled excited states 5F4 and 5S2 transferring to the ground state 5I8, respectively. The temperature-dependent population between 5F4 and 5S2 could be interpreted by Boltzmann's distribution in the range of 167–377 K. The relative sensitivities were calculated to be 6.14% K−1 at 167 K and 1.03% K−1 at 377 K, and the corresponding absolute sensitivities were estimated to be 0.09 × 10−3 K−1 and 2.11 × 10−3 K−1, respectively. The temperature resolution was calculated to be about 0.053 K at 167 K and 0.319 K at 377 K. The excellent repeatability of the NBT:Ho3+ ceramics was demonstrated by means of successive heating–cooling cycles in the range of 167–377 K. The above investigation results demonstrate the promising application of NBT:Ho in cryogenic optical thermometers.
研究领域:
材料科学
·
物理学
✓ 已验证
DOI
高影响因子
OPTICAL MATERIALS
·
2017
·
IF 2.238
Jianjian Sun,Bijun Fang,Shuai Zhang,Zhihui Chen,Jianning Ding,Xiangyong Zhao,Haosu Luo
Er 3+ -doped Na 0.5 Bi 0.5 TiO 3 (Er-doped NBT) ceramics were prepared via a hydrothermal method . High sintering active Er-doped NBT nano cubic particles with perovskite structure were synthesized at hydrothermal condition of 200 °C for 24 h in 12 M NaOH solution, which were self-assembled via in situ crystallization mechanism by the initially as-grown nanowires. The Er-doped NBT ceramics sintered at 1100 °C for 2 h exhibit pure rhombohedral perovskite structure, high densification and rather homogenous microstructure morphology. Under 488 nm light excitation , the strong green emission peaks centering at 530 nm and 550 nm and the weak red emission peaks locating at 665 nm and 735 nm are excited, which can be attributed to the 2 H 11/2 , 4 S 3/2 , 4 F 9/2 and 4 I 9/2 → 4 I 15/2 transitions, respectively. The maximum emission intensity is obtained when the Er doping content reaches 1.0 mol%. A strong upconversion emission peak centering around 550 nm in green light range is excited under 800 nm light excitation, which is correlated with the 4 S 3/2 → 4 I 15/2 transition.
研究领域:
材料科学
·
无机非金属材料
·
功能陶瓷
·
光电子学
·
固体化学
✓ 已验证
DOI
高影响因子
危险品化学品经营许可证（带存储）