Lead-free BaTiO3–Bi(Zn2/3Nb1/3)O3 weakly coupled relaxor ferroelectric materials for energy storage
Lead-free BaTiO3–Bi(Zn2/3Nb1/3)O3 weakly coupled relaxor ferroelectric materials for energy storage
复制标题
DOI：
10.1039/c5ra21261h
复制
发表时间：
2016-02
期刊：
影响因子：
3.9
通讯作者：
Longwen Wu;Xiao-hui Wang;Long-tu Li
中科院分区：
文献类型：
--
作者：
Longwen Wu;Xiao-hui Wang;Long-tu Li
采用固相反应法制备无铅（1−x） BaTiO3-xBi (Zn2/3Nb1/3)O3 （x = 0.05-0.20）材料。所有成分均获得了纯钙钛矿赝赝结构。介电测量结果显示，从5 mol%到20 mol% Bi(Zn2/3Nb1/3)O3的扩散和弛豫特性增强。从Vogel-Fulcher模型得出的x≥0.10的异常高的活化能（~ 0.20-0.22 eV）可以推断出弱耦合弛豫行为，这可能导致极低的介电非线性和极细的极化电场环路。在131 kV cm−1条件下，当x = 0.15时，BaTiO3-Bi (Zn2/3Nb1/3)O3材料的最佳放电能量密度为0.79 J cm−3，高能量效率为93.5%，证明了该材料是一种很有前景的高能量存储材料。
Lead-free (1 − x)BaTiO3–xBi(Zn2/3Nb1/3)O3 (x = 0.05–0.20) materials were fabricated via solid-state reactions. A pure perovskite pseudocubic structure is obtained for all compositions. Dielectric measurements reveal an intensified diffusion and relaxor-like characteristics from 5 mol% to 20 mol% Bi(Zn2/3Nb1/3)O3. Weakly coupled relaxor behavior is concluded from the exceptionally high activation energies of ∼0.20–0.22 eV from the Vogel–Fulcher model for x ≥ 0.10, which possibly results in the extremely low dielectric nonlinearity and extra slim polarization–electric field loops. An optimal discharged energy density of 0.79 J cm−3 with a high energy efficiency of 93.5% is achieved at 131 kV cm−1 for x = 0.15, which proves that the BaTiO3–Bi(Zn2/3Nb1/3)O3 material is a promising candidate for high energy storage applications.