Tuning polarization of sodium niobate-based ceramics by
NaNbO3 (NNO) is one of few Pb-free antiferroelectrics. But it commonly shows ferroelectricity due to the irreversible transition from antiferroelectric to ferroelectric. By adding Sr(Fe0.5Nb0.5)O3 (SFN), a novel dielectric ceramic (1 − x)NNO–xSFN has been prepared by a conventional solid reaction method. The ceramic is the pure phase with x up to 0.15. With …
Studies of Crystallization Kinetics of Eu-doped Sodium Niobate …
The ABO 3 stoichiometry, particularly the perovskite variants, stands out due to their diverse structural phase transitions and applications in non-linear optics [].Among these, sodium niobate (NaNbO 3), characterized by intriguing electrical, chemical, and mechanical properties, holds promise for various technological uses [].At room temperature, pure NaNbO 3 …
Research progress of high piezoelectric activity of potassium sodium ...
Research progress of high piezoelectric activity of potassium sodium niobate based lead-free ceramics Xing Jie Tan Zhi Zheng Ting Wu Jia-Gang Xiao Ding-Quan Zhu Jian-Guo Citation: Acta Physica Sinica, 69, 127707 (2020) DOI: 10.7498/aps.69.20200288
Temperature-insensitive electrical performance of the potassium sodium ...
alent: barium titanate (BaTiO3, BT), potassium sodium niobate (K0.5Na0.5NbO3, KNN), and bismuth sodium titanate (Na0.5Bi0.5TiO3, BNT). Barium titanate-based ceramics can achieve high piezoelectric properties (d33 > 400pC/N) through phase boundary modulation and grain size control [6–9], but the low curie tem-
The seven phases of sodium niobate | Semantic Scholar
Abstract Sodium niobate, NaNbO3, has seven structures belonging to the perovskite family, comprising the aristotype 1 (with the ideal perovskite structure) and six hettotypes 1 (structures with lower symmetry). The differences between them can be systematized in terms of two factors, displacement of Nb from the octahedron centres, and tilting (rotation) of octahedra about the …
Cold sintering of the ceramic potassium sodium niobate
Cold Sintering was applied to densify a Potassium-Sodium Niobate solid solution composition, 0.5KNbO3-0.5NaNbO3 (KNN); the process uses a transient chemical sintering aid, moderate pressure (400 ...
Facile construction of single-crystalline sodium niobate anode ...
Electrode materials structures hold the key to enhance the performance. Based on the time-dependent growth process of niobium precursor, single-crystal Na2Nb2O6·nH2O nanowires and NaNbO3 nanocubes were successfully synthesized through a facile and friendly hydrothermal route at 180 °C under different reaction times. NaNbO3 nanowires were derived …
Enhanced piezoelectric properties for potassium sodium niobate …
Potassium-sodium niobate (Na, K)NbO 3 (NKN) powder was synthesized at low temperature via microwave-assisted hydrothermal solovthermal method (MHSM). The resultant powder was characterized by X-ray diffraction (XRD) and scanning electron microscope (SEM). XRD results showed that pure (Na, K)NbO 3 powder with a single perovskite structure was successfully …
Piezoelectric and Dielectric Properties of Ceramics in the System ...
High radial coupling coefficients are observed for compositions having up to 50 mole % sodium niobate additions to potassium niobate. The activity diminishes with additional sodium niobate content and disappears beyond about 98 mole % additions. Dielectric constants are relatively low, varying from 450 to 125, depending on composition. A.-c. losses are high and d.-c. resistivities …
Research progress of high piezoelectric activity of potassium sodium ...
Potassium sodium niobate (K0.5Na0.5)NbO3 (KNN) lead-free piezoelectric ceramics are considered as one of the most promising material systems to substitute for lead-based piezoelectric ceramics ...
Hydrothermal synthesis of potassium–sodium niobate …
Potassium–sodium niobates (K x Na 1− x NbO 3, 0 < x < 1, KNN) were hydrothermally synthesized under varying alkaline ratios (K + /Na +), total hydroxide concentration, reaction temperature, and time positional …
Tuning of defect structure and electrical properties for potassium ...
Oxides addition has been realized as an effective way to promote macro performance in potassium sodium niobate (KNN) ceramics, which is crucial for practical applications. Herein, the influence of different oxides (Fe2O3 and Fe2O3 & MnO2) on defect structure and electrical properties as well as temperature stability is explored in KNN-based …
Giant Piezoelectricity in Potassium–Sodium Niobate Lead-Free …
Environment protection and human health concern is the driving force to eliminate the lead from commercial piezoelectric materials. In 2004, Saito et al. [Saito et al., Nature, 2004, 432, 84.] developed an alkali niobate-based perovskite solid solution with a peak piezoelectric constant d33 of 416 pC/N when prepared in the textured polycrystalline form, intriguing the enthusiasm of …
Free-standing sodium niobate nanowires film ...
Therefore, this research aims to provide a follow-up of our previous work [16], where it was reported the synthesis, film growth mechanisms, and characterization of niobium-containing oxides supported on a niobium sheet (self-supported electrode).Thus, this work presents the development and characterization of a novel free-standing sodium niobate …
Multi-iteration active learning for the composition design of …
Chemical modification effectively enhances the piezoelectric properties of KNN-based materials [7].The dopant selection plays a crucial role in creating phase coexistence, which can improve the piezoelectric performance [[8], [9], [10]].Most high-performance KNN ceramics (d 33 > 350 pC/N) reported over the past decade have been chemically modified by multiple …
New potassium-sodium niobate ceramics with a giant d33.
A giant piezoelectric constant is reported in (1-x)(K0.48Na0.52)(Nb0.95Sb 0.05)O3-xBi0.5ZrO3 lead-free ceramics to benefit the sustainable development of (K,Na)NbO3 materials. For potassium-sodium niobate, poor piezoelectric properties always perplex most researchers, and then it becomes important to attain a giant piezoelectricity. Here we reported …
COMPARATIVE ANALYSIS OF THE PROPERTIES OF SODIUM NIOBATE AND SODIUM ...
The objective of this review is to focus on the processing of ceramics based on sodium potassium niobate (K0.5Na0.5NbO 3) as promising candidates for lead-free piezoelectrics.
A review of potassium sodium niobate and bismuth sodium …
This paper will focus on two groups: bismuth sodium titanate (BNT) based, potassium sodium niobate (KNN) based on piezoelectric materials to narrow the scope in order to improve comprehensibility. Bismuth ferrite (BF) and barium titanate (BT) based piezoceramics will be left for the scope of another review study.
Enhanced Energy Storage Performance of Sodium Niobate …
Sodium niobate (NaNbO3)-based lead-free ceramics have been actively studied for energy storage applications because of their antiferroelectric and/or relaxor features achieved in modified systems. The P–E loops of NaNbO3-based ceramics are usually hysteretic because of the existence of a metastable ferroelectric phase at room temperature. In this study, by …
High mechanical quality factor and piezoelectricity in potassium sodium ...
Potassium-sodium niobate (K, Na)NbO 3 (KNN) ceramics are one of the best substitutes of PZT. They have a series of phase transitions as the temperature varies, changing from rhombohedral to orthorhombic at ∼ -123 °C, from orthorhombic to tetragonal at ∼200 °C and then from tetragonal to cubic at ∼410 °C [3].Pure KNN ceramics own piezoelectric constant (d …
Enhanced electrical properties of lead-free sodium potassium niobate ...
Here we summarized nano-domains and PNRs of three representative lead-free piezoceramics (i.e., potassium sodium niobate, barium titanate, and sodium bismuth titanate), focusing on their effects ...
Sodium niobates and protonic niobates nanowires obtained from ...
Dehydrated sodium niobate (Na2Nb2O6) and sodium niobate with perovskite structure (NaNbO3) were obtained by submitting Na2Nb2O6.H2O to heat treatment (350 °C and 500 °C, respectively).
Enhanced energy storage and mechanical properties in niobate …
Extraordinary energy storage performance and thermal stability in sodium niobate-based ceramics modified by the ion disorder and stabilized antiferroelectric orthorhombic R phase J. Mater. Chem.
Textured Potassium Sodium Niobate Lead-Free Ceramics with …
Potassium sodium niobate (KNN) lead-free piezoceramics have garnered significant attention for their environmentally friendly attributes, desired piezoelectric activity (d 33), and high Curie temperature (T c).However, the limited applicability of most KNN systems in high-power apparatus, including ultrasonic motors, transformers, and resonators, persists due to the …