High dielectric constant and tunability of strontium titanate ceramics modified by chromium doping
High dielectric constant and tunability of strontium titanate ceramics modified by chromium doping
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DOI：
10.1088/0953-8984/20/41/415224
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发表时间：
2008-10-15
影响因子：
2.7
通讯作者：
Kholkin, Andrei L.
中科院分区：
文献类型：
--
作者：
Tkach, Alexander;Okhay, Olena;Kholkin, Andrei L.
本文研究了铬掺杂对钛酸锶陶瓷的结构、微结构和低频介电性能的影响。用溶胶-凝胶法制备了致密的Sr1-1.5xCrxTiO3(x=0，0.0005，0.0010，0.0015)陶瓷。所研究的所有陶瓷样品的晶胞参数接近3.906埃，平均晶粒度接近2.5um。另一方面，当x=0.0005时，介电常数从大约7000增加到>；16000。对低温介电性能的详细研究表明，掺铬钛酸锶陶瓷的介电常数随直流偏置电场的变化具有明显的可调性和非线性度，但没有表现出铁电或类弛豫行为。这些结果表明，少量的铬可能掺杂在钛酸锶陶瓷的锶晶位上，从而拓展了钛酸锶材料的可调谐应用。
The incorporation of chromium on the strontium site of the perovskite lattice of SrTiO3 ceramics and its influence on the structural, microstructural and low-frequency dielectric properties is studied in this work. Dense Sr1-1.5xCrxTiO3 (x = 0, 0.0005, 0.0010, 0.0015) ceramics are prepared from powders obtained by a sol-gel method. The lattice parameter similar to 3.906 angstrom and average grain size similar to 2.5 mu m are almost identical for all the ceramic samples under study. On the other hand, the dielectric constant increases from approximately 7000 for x = 0 to > 16 000 for x = 0.0005. Detailed investigations of the low-temperature dielectric properties show a remarkable increase of the tunability and nonlinearity of the dielectric constant as a function of dc bias field in strontium titanate ceramics modified by chromium doping but no ferroelectric or relaxor-like behaviour. These results imply the possible incorporation of small Cr amounts on the Sr site of strontium titanate ceramics and expand the tunable applications of SrTiO3-based materials.