2025-10-29 ペンシルベニア州立大学
＜関連情報＞
- https://www.psu.edu/news/earth-and-mineral-sciences/story/good-vibrations-ceramic-material-harvests-electricity-waste-energy
- https://onlinelibrary.wiley.com/doi/10.1002/smll.202505193
高い熱安定性と電気品質係数を備えたテクスチャ加工された鉛フリーセラミック Textured Lead-Free Ceramic with High Thermal Stability and Electrical Quality Factor
Aman Nanda, Sumanta Kumar Karan, Shankar Kunwar, Yongke Yan, Mark Fanton, Shashank Priya, Michael Lanagan, Bed Poudel
Small Published: 24 September 2025
DOI:https://doi.org/10.1002/smll.202505193
Abstract
A major challenge with (K,Na)NbO3 compositions is maintaining high piezoelectric figures of merit (FOM) in a wide range of temperatures and electric fields. A textured composition is demonstrated, K0.48Bi0.02Na0.5Nb0.92Sb0.04Zr0.04O3 incorporating 3 wt.% NaNbO3 templates, that exhibits a d33 of 570 pC/N and k31 of 0.4 at room temperature. Additionally, a high texture degree of ≈98% is achieved with the desired microstructural orientation. Electrical quality factor (Qe = 1/tan δ) is effectively improved from 22 to 33 with 0.1 mol% MnO2 doping. The strain response (Smax/Emax) is calculated to be 450 pm V−1 under 40 kV cm−1, and P–E and S–E loops exhibited excellent fatigue resistance up to 106 cycles. To validate the practical relevance, the energy harvesting performance is explored under both on-resonance and off-resonance conditions using vibration velocity measurement and a cantilever type energy harvester, respectively. The maximum output power recorded is ≈50 µW with a volume power density of ≈2 µW mm−3. The vibration velocity reached 0.26 m s−1 under a drive voltage of 30 V mm−1 at resonance. Through the combination of defect engineering (Mn doping) and microstructural engineering (texturing), the results confirm an excellent combination of electromechanical properties along with thermal stability and fatigue resistance in this material system.
