中国物理B ›› 2011, Vol. 20 ›› Issue (6): 67701-067701.doi: 10.1088/1674-1056/20/6/067701

• • 上一篇    下一篇

Effects of A-site non-stoichiometry on the structural and electrical properties of 0.96K0.5Na0.5NbO3–0.04LiSbO3 lead-free piezoelectric ceramics

徐卓1, 张红梅2, 屈绍波3, 赵静波4, 杜红亮4   

  1. (1)Electronic Materials Research Laboratory (Key Laboratory of the Ministry of Educatio14), Xián Jiaotong University, Xián 710049, China; (2)The College of Science, Air Force Engineering University, Xián 710051, China; (3)The College of Science, Air Force Engineering University, Xián 710051, China;Electronic Materials Research Laboratory (Key Laboratory of the Ministry of Education),Xián Jiaotong University, Xián 710049, China; (4)The College of Science, Air Force Engineering University, Xián 710051, China;State Key Laboratory of Electrical Insulation and Power Equipment, Xián Jiaotong University, Xián 710049, China
  • 收稿日期:2010-10-15 修回日期:2011-01-19 出版日期:2011-06-15 发布日期:2011-06-15
  • 基金资助:
    Project supported by the National Natural Science Foundation of China (Grant Nos. 10804130 and 60871027), the Natural Science Foundation of Shaanxi Province of China (Grant No. 2009JQ1001), and the Funds of the Key Laboratory of Electrical Insulation and Power Equipment (Grant No. EIPE10202).

Effects of A-site non-stoichiometry on the structural and electrical properties of 0.96K0.5Na0.5NbO3–0.04LiSbO3 lead-free piezoelectric ceramics

Zhao Jing-Bo(赵静波)a)b), Du Hong-Liang(杜红亮)a)b), Qu Shao-Bo(屈绍波) a)c)†, Zhang Hong-Mei(张红梅)a), and Xu Zhuo(徐卓) c)   

  1. a The College of Science, Air Force Engineering University, Xi'an 710051, China; b State Key Laboratory of Electrical Insulation and Power Equipment, Xi'an Jiaotong University, Xi'an 710049, China; c Electronic Materials Research Laboratory (Key Laboratory of the Ministry of Education), Xi'an Jiaotong University, Xi'an 710049, China
  • Received:2010-10-15 Revised:2011-01-19 Online:2011-06-15 Published:2011-06-15
  • Supported by:
    Project supported by the National Natural Science Foundation of China (Grant Nos. 10804130 and 60871027), the Natural Science Foundation of Shaanxi Province of China (Grant No. 2009JQ1001), and the Funds of the Key Laboratory of Electrical Insulation and Power Equipment (Grant No. EIPE10202).

摘要: Effects of A-site non-stoichiometry on the structural and electrical properties of 0.96K0.5 + xNa0.5 + xNbO3-0.04LiSbO3 lead-free piezoelectric ceramics were examined for 0 ≤ x ≤ 0.02. The piezoelectric coefficients exhibited a maximum, d33= 187 pC/N at x=0.0075, coinciding with the maximum of the grain size and the apparent density at x=0.0075. The apparent density and the piezoelectric coefficients decreased with increasing x at higher x which was likely due to the crystal geometrical distortion of 0.96K0.5 + xNa0.5 + xNbO3-0.04LiSbO3. In addition, super-large grains were found and this may be due to liquid phase sintering. Excess (K++Na+) attracted a sum of space charges to keep the charge neutral, resulting in charge leakage during the course of ceramic polarization, influencing the piezoelectric and ferroelectric properties. These findings are of importance for guiding the design of K0.5Na0.5NbO3-based lead-free ceramics with enhanced electrical properties.

关键词: lead-free ceramics, piezoelectric, non-stoichiometry, K0.5Na0.5NbO3

Abstract: Effects of A-site non-stoichiometry on the structural and electrical properties of 0.96K0.5 + xNa0.5 + xNbO3-0.04LiSbO3 lead-free piezoelectric ceramics were examined for 0 ≤ x ≤ 0.02. The piezoelectric coefficients exhibited a maximum, d33= 187 pC/N at x=0.0075, coinciding with the maximum of the grain size and the apparent density at x=0.0075. The apparent density and the piezoelectric coefficients decreased with increasing x at higher x which was likely due to the crystal geometrical distortion of 0.96K0.5 + xNa0.5 + xNbO3-0.04LiSbO3. In addition, super-large grains were found and this may be due to liquid phase sintering. Excess (K++Na+) attracted a sum of space charges to keep the charge neutral, resulting in charge leakage during the course of ceramic polarization, influencing the piezoelectric and ferroelectric properties. These findings are of importance for guiding the design of K0.5Na0.5NbO3-based lead-free ceramics with enhanced electrical properties.

Key words: lead-free ceramics, piezoelectric, non-stoichiometry, K0.5Na0.5NbO3

中图分类号:  (Piezoelectric and electrostrictive constants)

  • 77.65.Bn
77.80.B- (Phase transitions and Curie point) 77.84.-s (Dielectric, piezoelectric, ferroelectric, and antiferroelectric materials)