Journal of Materials Chemistry A
·
2025
·
IF 9.5
Yingzhi Meng,Zhaojie Wang,Xiang Niu,Yuleng Jiang,Peng Nong,Silin Tang,Jiyang Xie,Wanbiao Hu,Dingyuan Wang,Biaolin Peng,Shengguo Lu,Laijun Liu
The development of high-performance electrocaloric effect (ECE) is of great importance for local refrigeration (such as chip and wearable electronics cooling, etc.). However, how to simultaneously achieving both a large ECE and a wide working temperature range near the room temperature are long-term challenges for lead-free ceramics. Herein, we report a novel lead-free ceramic with a high-performance ECE. Phase coexistence and optimized ferroelectric domain configuration and ultra-fine grains were constructed by {Nb 5+ , In 3+ } co-doping in B 0.9 Ca 0.1 TiO 3 ceramics near the room temperature. Ultimately, an ultrahigh ECE of 3.0 K and a wide working temperature range of 97 K are obtained near the room temperature in the composition (B 0.9 Ca 0.1 Ti 0.89 (Nb 0.5 In 0.5 ) 0.11 O 3 ). Furthermore, the origin of the high ECE performance was elucidated by the microstructures characterized using piezoresponse force microscopy (PFM) and atomic-resolution HAADF-STEM, and the dielectric and ferroelectric properties. This work provides an innovative approach for achieving high-performance ECE.
✓ 已验证
产品关联
DOI
高影响因子
CERAMICS INTERNATIONAL
·
2015
·Vol. 41
·期 4
·5498-5504
·
IF 2.605
Shizhou Pu,He Zheng,Zhenlian Chen,Meiya Li,Zhongqiang Hu,Jianbo Wang,Huamin Zou
The microstructures of Bi 0.85 Nd 0.15 FeO 3 ceramics were investigated by using transmission electron microscopy (TEM), high-resolution transmission electron microscopy (HRTEM), selected area electron diffraction (SAED), convergent-beam electron diffraction (CBED) and X-ray energy dispersive spectrometry (EDS). The superstructure phase related to 1/4( hh 0) p and 1/4(00 l ) p diffraction spots were observed in the samples. It is found that the superstructure phase can co-exist with R 3 c phase in a single grain. The bright and dark field images accompanied with SAED patterns provided evidences of the superstructure phase dispersed into the matrix with R3c symmetry and evolution of the domain. The ferroelectric domain wall was observed according to the displacement of Fe 3+ ions respect to Bi 3+ sub-lattice in the ferroelectric R 3 c phase based on HRTEM observations. The space group Pnam of the superstructure was identified by combining SAED and CBED techniques . EDS measurement revealed that the concentration of Nd in the Pnam phase is higher than that in R 3 c phase. This might mean that the transition from R 3 c to Pnam structure is due to the inhomogeneous distribution of the Nd concentration and the weakened stereochemical activity of Bi 3+ lone electron pair, arisen from the increase in Nd content.
研究领域:
材料科学
·
凝聚态物理
·
功能陶瓷
·
电子显微学
·
铁电材料
·
多铁材料
✓ 已验证
DOI
高影响因子
CERAMICS INTERNATIONAL
·
2025
·
IF 5.6
Zhe Zhu,Zhonghua Yao,Xinhui Li,Rui Zhao,Ruiling Chang,Hua Hao,Minghe Cao,Hanxing Liu
The quenching process is investigated to modulate domain structures behaviors in three ceramic compositions: lead zirconate titanate with a 75/25 zirconium titanium ratio (75/25PZT), Mn-doped (Mn-75/25PZT) and Nb-doped (Nb-75/25PZT). Piezoresponse force microscopy (PFM) demonstrates a transformation of domain structures from micron to nanoscale, accompanied by increased domain walls (DWs) density. In-situ Raman spectroscopy detects a softening of the E (TO1) vibration mode after quenching, indicating lower DWs energy density and higher internal stress. Furthermore, both 75/25PZT and Mn-75/25PZT demonstrate the release of pinched hysteresis loops, coupled with substantial enhancements in piezoelectric coefficients of 36 % and 37 %, respectively. Additionally, both reversible and irreversible dielectric responses are augmented through quenching. This investigation provides detailed insights into the evolution of domains during the quenching process in these ceramic systems.
✓ 已验证
产品关联
DOI
高影响因子
ACS Applied Materials & Interfaces
·
2025
·
IF 8.2
Junhui Lang,Mingwang Yuan,Yingzhi Meng,Silin Tang,Biao Zhang,Qingqing Ke,Laijun Liu
Piezoelectric energy harvesters (PEHs) have attracted much attention due to their efficient harvesting of vibrational energy from the ambient environment, which demonstrates great potential applications. Unfortunately, their low energy density severely hinders the further development of PEHs. Therefore, it is highly desirable to search for piezoelectric materials with a high transduction coefficient (d33 × g33). In this work, an excellent d33 × g33 is achieved in Pb0.94(La0.06-xNdx) (Zr0.58Ti0.42)0.985O3 (x = 0, 0.01, 0.02, 0.03, and 0.04) (PL0.06-xNxZT) ceramics by composition modulation. The best d33 × g33 of 26.71 pm2/N is obtained with an optimal composition of x = 0.02. Moreover, a superior output voltage of 28.4Vp and power density of 15.93 μW/mm3 are simultaneously obtained for the sample applied in the PEH system. The sizes of the polar nanodomains of the samples are estimated using a phenomenological statistical model, and the domain configuration is observed using PFM. Our results indicate that composition modulation in PLZT can regulate and awaken ferroelectric domains, giving rise to an ultrahigh d33 × g33, which consequently results in enhanced performance of the output voltage and power density of PEHs.
研究领域:
材料科学
·
压电能量收集
·
陶瓷
·
功能材料
✓ 已验证
产品关联
DOI
PubMed
高影响因子
危险品化学品经营许可证（带存储）