Abstract A core-shell synthesis is applied to CaCu3Ti4O12, a material that shows colossal permittivity. The objective was to test several bulk permittivity of the shell material in order to reach a large capacity of the grain boundaries after sintering. The permittivity is improved with certain shells while the bulk resistivity reaches levels approaching that of commercial grain boundary barrier layer (GBBL) ceramic capacitors. The highest permittivity is confirmed to be related to the highest capacity of grain boundaries. The bulk resistivity is related to that of grain boundaries. If one attaches the more important weight to a high bulk resistivity without need of permittivity larger than 15,000, as in commercial GBBL ceramic capacitors, several samples appear convenient. On the other hand, much higher permittivity can be reached like in CCTO with a shell of TiO2 but at the expense of dielectric losses, possibly due to oxygen departure from stoichiometry. Thermal post-treatment under various controlled atmosphere have been applied to reduce dielectric losses.

中文翻译：

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CaCu3Ti4O12 (CCTO) 陶瓷的核壳合成显示出巨大的介电常数和低电损耗，可用于电容器

摘要 CaCu3Ti4O12 是一种具有巨大介电常数的材料，采用核壳合成法。目的是测试壳材料的几种体介电常数，以便在烧结后达到大容量的晶界。某些外壳的介电常数得到改善，而体电阻率达到接近商业晶界阻挡层 (GBBL) 陶瓷电容器的水平。最高介电常数被证实与最高的晶界容量有关。体电阻率与晶界有关。如果在不需要大于 15,000 的介电常数的情况下将更重要的权重附加到高体电阻率上，如商用 GBBL 陶瓷电容器，几个样品似乎很方便。另一方面，可以达到更高的介电常数，就像在 CCTO 中使用 TiO2 外壳一样，但以介电损耗为代价，这可能是由于氧偏离化学计量。在各种受控气氛下进行热后处理以减少介电损耗。