Co-substitution of Eu and Nb into insulating CaTiO can make it a good n-type potential thermoelectric (TE) material. In the present work, solid solution compounds with the nominal composition CaEuTiNbO ( = 0.05, 0.08, 0.1, 0.12) were synthesized and sintered in different atmospheres, including argon (Ar) and forming gas (5 vol% H in Ar). Notably, the different reduction effects of these atmospheres resulted in significant differences in phase formation, grain size, oxygen deficiency, and TE properties of the synthesized samples. Introducing additional electrons to the system by donor substitution of Ti with Nb leads to significant changes in the electrical conductivity and Seebeck coefficient. The most favorable TE performance of the prepared samples was found in the sample with = 0.05, primarily attributed to its proper charge carrier concentration. This work highlights the crucial role of the sintering atmosphere in manipulating the TE performance of n-type CaTiO-based ceramics, an effect similar to donor doping.

中文翻译：

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Nb替代及烧结气氛对CaTiO3基陶瓷热电性能的影响

将Eu和Nb共取代到绝缘CaTiO中可以使其成为良好的n型势热电（TE）材料。在目前的工作中，合成了标称成分为 CaEuTiNbO (= 0.05、0.08、0.1、0.12) 的固溶体化合物，并在不同的气氛中进行烧结，包括氩气 (Ar) 和合成气体（Ar 中含有 5 vol% H2）。值得注意的是，这些气氛的不同还原效应导致合成样品的相形成、晶粒尺寸、缺氧和TE性能显着差异。通过用 Nb 取代 Ti 的供体向系统引入额外的电子，会导致电导率和塞贝克系数发生显着变化。在 = 0.05 的样品中发现了所制备样品最有利的 TE 性能，这主要归因于其适当的载流子浓度。这项工作强调了烧结气氛在控制 n 型 CaTiO 基陶瓷的 TE 性能方面的关键作用，其效果类似于施主掺杂。