Donor-doped CaMnO₃ is an n-type semiconductor with perovskite structure, being considered as a potential n-type leg in thermoelectric modules. This oxide presents stability at high temperatures and allows tuning the relevant electrical and thermal transport properties through doping. In this work, Ca_0.9Gd_0.1MnO₃ precursors have been prepared to produce fibres through the laser floating zone technique using different pulling rates. However, as-grown fibres did not present thermoelectric properties due to the presence of high amounts of secondary phases, leading to very high electrical resistivity values. The results have highlighted the importance of annealing procedures to reduce electrical resistivity, due to the decrease of secondary phases amount, and producing promising thermoelectric performances. The annealed samples present higher ZT values when the growth rate is decreased, reaching around 0.22 for the lowest growth rate, which is very close to the best values reported in the literature for these materials. Moreover, this procedure possesses an additional advantage considering that these samples can be directly used as n-type legs in thermoelectric modules for high-temperature applications. However, further studies should be made to determine the optimal amount of dopant.

施主掺杂的CaMnO ₃是具有钙钛矿结构的n型半导体，被认为是热电模块中潜在的n型分支。该氧化物在高温下表现出稳定性，并允许通过掺杂来调节相关的电和热传输性质。在这项工作中，Ca _0.9 Gd _0.1 MnO ₃通过使用不同的拉速，通过激光浮区技术已经制备了前体以生产纤维。然而，由于存在大量的次级相，所以生长的纤维不具有热电性能，导致非常高的电阻率值。结果强调了退火工艺对于降低电阻率的重要性，这归因于次级相量的减少以及产生有希望的热电性能。当生长速率降低时，退火样品呈现更高的ZT值，最低生长速率达到0.22左右，这非常接近文献中针对这些材料报道的最佳值。此外，该程序具有一个附加的优点考虑，这些样品可以直接用作Ñ用于高温应用的热电模块中的三脚型脚。但是，应该做进一步的研究以确定最佳的掺杂剂量。