Article
Materials Science, Multidisciplinary
Jin Luo, Lisha Liu, Su-Wei Zhang, Jing-Feng Li
Summary: The study prepared epitaxial (K,Na)NbO3 (KNN)-based thin films using a sol-gel method and observed stripe-shaped domain patterns with charged domain walls in the films, suggesting potential for exploring functional charged domain walls through strain engineering.
PHYSICA STATUS SOLIDI-RAPID RESEARCH LETTERS
(2021)
Article
Chemistry, Multidisciplinary
Alexander M. Grishin
Summary: Densely woven highly crystallized biocompatible sodium-potassium niobate Na0.35K0.65NbO3 fibers were successfully prepared using the sol-gel calcination-assisted electrospinning technique. The study confirmed the preferential cube-on-cube [001] orientation of nanocrystals within the fiber's body and analyzed the size and intrinsic strain of nanocrystal fiber aggregates using XRD and TEM. The potential capacity of direct XRD analysis to noninvasively control crystallite size and lattice distortion in core-shell coaxial nanofibers was investigated.
Article
Chemistry, Physical
Yu Huang, Liang Shu, Fade Hu, Lisha Liu, Zhen Zhou, Yue-Yu-Shan Cheng, Suwei Zhang, Wei Li, Qian Li, Hongliang Wang, Zhinan Dong, Liyu Wei, Chuan Luo, Jing-Feng Li
Summary: Piezoelectric micromachined ultrasonic transducers (pMUTs) have attracted widespread attention due to their important applications in medical imaging, fingerprint identification, range-finding, and gesture recognition. However, the toxicity of lead limits the use of piezoelectric Pb(Zr, Ti)O-3 (PZT) in medical-related applications. This study successfully developed lead-free (K,Na)NbO3 (KNN) based pMUTs, which achieved an ultrahigh transmitting sensitivity.
Article
Chemistry, Multidisciplinary
Eunmi Im, Seonhwa Park, Geon-Tae Hwang, Dong Choon Hyun, Yuho Min, Geon Dae Moon
Summary: A single-crystal-based (K,Na)NbO3 (KNN) microcuboid/CuO nanodot heterostructure with enhanced photo-piezocataytic activity is reported. Compared to polycrystalline KNN powders and bare KNN single-crystals, the single-crystal-based KNN/CuO exhibits higher piezocatalytic degradation activities. The excellent photo-piezocatalytic activity is attributed to the enhanced charge-carrier separation and proper alignment of band structure.
Article
Chemistry, Multidisciplinary
Da Li, Di Zhou, Dong Wang, Weichen Zhao, Yan Guo, Zhongqi Shi
Summary: The study optimized the energy storage properties of (K, Na)NbO3-based ceramics using a combinatorial optimization strategy, achieving ultrahigh recoverable energy density and high efficiency. By inducing polar nanoregions and improving breakdown strength, the performance of the ceramics was further enhanced, with excellent temperature stability.
ADVANCED FUNCTIONAL MATERIALS
(2022)
Article
Nanoscience & Nanotechnology
Yiming Ma, Shaoxin Yang, Chunlin Zhao, Cong Lin, Jinfeng Lin, Xiao Wu, Min Gao, Tengfei Lin, Changqing Fang
Summary: Rare earth Tb3+ doped lead-free transparent ferroelectric ceramics were designed and prepared. The effects of Tb3+ on phase structure, microstructure, optical transmittance, photoluminescence, and photochromic behaviors were studied. The ceramics showed high optical transmittance and reversible photochromic modulation, with improved luminescence contrast under in-situ electric field stimulation.
ACS APPLIED MATERIALS & INTERFACES
(2022)
Article
Nanoscience & Nanotechnology
Yiming Ma, Shaoxin Yang, Chunlin Zhao, Cong Lin, Jinfeng Lin, Xiao Wu, Min Gao, Tengfei Lin, Changqing Fang
Summary: Rare earth Tb3+ doped lead-free transparent ferroelectric ceramics were designed and prepared, showing high optical transmittance of 74% and reversible photochromic modulation. The ceramics have potential applications in optical data storage and anticounterfeiting due to their unique properties.
ACS APPLIED MATERIALS & INTERFACES
(2022)
Article
Physics, Applied
Kiyotaka Tanaka, Rei Ogawa, Sang Hyo Kweon, Goon Tan, Isaku Kanno
Summary: Epitaxial KNN thin films were deposited on substrates, and the effects of post-annealing on the as-deposited films were investigated. The crystal structure changed and the polarization-electric field hysteresis loop became asymmetric after annealing. The stable spontaneous polarization direction changed and a high converse piezoelectric coefficient was obtained.
JAPANESE JOURNAL OF APPLIED PHYSICS
(2022)
Article
Nanoscience & Nanotechnology
Nan Zhang, Xiang Lv, Xi-xiang Zhang, Anyang Cui, Zhigao Hu, Jiagang Wu
Summary: By controlling the long-range ferroelectric ordering (LRFO) in lead-free piezoceramics, multifunctional properties such as increased piezoelectric coefficient and temperature-insensitive strain can be achieved. Low antimony doping maintains LRFO and results in multi-phase coexistence near room temperature, while high antimony doping leads to a relaxor phase transition.
ACS APPLIED MATERIALS & INTERFACES
(2021)
Article
Physics, Applied
Kiyotaka Tanaka, Rei Ogawa, Sang Hyo Kweon, Goon Tan, Isaku Kanno
Summary: By using rapid thermal annealing (RTA), the crystal structure of lead-free epitaxial K0.47Na0.53)NbO3 (KNN) thin films can be improved, reducing the generation of oxygen vacancies and A-site vacancies at the interface. This leads to an improvement in the converse piezoelectric coefficient of the epitaxial KNN/Si unimorph cantilever due to the decrease in defect density resulting from RTA.
JAPANESE JOURNAL OF APPLIED PHYSICS
(2023)
Article
Physics, Applied
Xinyan Chen, Feng Jin, Teng Li, Liqiang Xu, Zhen Huang, Ke Wang, Feng Chen
Summary: The influence of growth oxygen pressure on the performance of lead-free ferroelectric films is investigated, showing effects on tetragonality change, dielectric constant enhancement, and leakage current density suppression. The results indicate GP(O2) as a key factor in regulating ferroelectricity and phase transition temperature of the films.
JOURNAL OF APPLIED PHYSICS
(2021)
Article
Materials Science, Multidisciplinary
Mao-Hua Zhang, Qinghua Zhang, Ting-Ting Yu, Geng Li, Hao-Cheng Thong, Li-Ying Peng, Lisha Liu, Jing Ma, Yang Shen, Zhijian Shen, John Daniels, Lin Gu, Bing Han, Long-Qing Chen, Jing-Feng Li, Fei Li, Ke Wang
Summary: This study proposes to use microstructural engineering to enhance the electric-field-induced strain of lead-free piezoelectrics. Through precise compositional tuning, enhanced properties were achieved by introducing heterogeneous ferroelectric-paraelectric microstructures, which significantly increased electric-field-induced strain.
Article
Physics, Applied
Xiangjian Wang, Xiaojie Lou, Wenping Geng, Yingbang Yao, Tao Tao, Bo Liang, Sheng-Guo Lu
Summary: The K0.5Na0.5NbO3-based ceramic demonstrated excellent performance and enhanced properties in terms of electrocaloric, dielectric energy storage, and piezoelectric characteristics through the design of multi-element dopants for polymorphic phase boundary formation.
JOURNAL OF APPLIED PHYSICS
(2021)
Article
Nanoscience & Nanotechnology
Xueyou Yuan, Kazuki Okamoto, Mitsuki Kawano, Masahito Yoshino, Takanori Nagasaki, Yasuhiko Imai, Osami Sakata, Tomoaki Yamada
Summary: This study quantitatively probes the contributions of ferroelastic domain switching and electric-field induced lattice strain to the piezoelectric response in a ferroelectric monoclinic phase. The results reveal that the contribution of domain switching to the strain is larger than the total strain of the film, providing a knowledge platform for the future development of lead-free piezoelectric microelectromechanical and nanoelectromechanical systems.
ADVANCED ELECTRONIC MATERIALS
(2023)
Article
Chemistry, Physical
Oliver Paull, Changsong Xu, Xuan Cheng, Yangyang Zhang, Bin Xu, Kyle P. Kelley, Alex de Marco, Rama K. Vasudevan, Laurent Bellaiche, Valanoor Nagarajan, Daniel Sando
Summary: Epitaxial strain and orientation engineering have been combined to create a low-symmetry phase of BiFeO3 with enhanced piezoelectric response, which undergoes a transition to the tetragonal-like polymorph under electric field. This results in an enhanced piezoelectric response throughout the film and associated field-induced reversible strains. This approach offers a way to improve the functionalities of thin-film piezoelectrics, with potential applications in other functional oxides.