The influence of copper addition (0.5–2 mol%) on the crystal structure, densification microstructure, and electrochemical properties of Ce_0.8Gd_0.2O_1.9 synthesized in a one-step sol–gel combustion synthesis route has been studied. It has been found that Cu is very active as sintering aids, with a significative reduction of GDC firing temperature. A reduction of 500 °C with a small amount of copper (0.5 mol%) was observed achieving dense bodies with considerable ionic conductivities. Rietveld refined was used to investigate the crystal structure while relative density and microstructural examination were performed in the sintering temperature range of 1000–1200 °C after dilatometer analysis. High dense bodies were fabricated at the lowest sintering temperature, which promotes the formation of Ce_0.8(1−x)Gd_0.2(1−x)Cu_xO_{[1.9(1−x)+x]} solid solution and the absence of secondary phase Cu-rich or the segregation or copper at the grain boundary. As compared to the pure GDC an improvement of total conductivity was achieved with a maximum for the highest copper content of 2.23·10⁻³–9.19·10⁻² S cm⁻¹ in the temperature range of 200–800 °C.

中文翻译：

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用于IT-SOFC的Ce0.8（1-x）Gd0.2（1-x）CuxO [1.9（1-x）+ x]电解质的微观结构和电化学性能评估

添加铜（0.5–2 mol％）对Ce _0.8 Gd _0.2 O _1.9的晶体结构，致密化微观结构和电化学性能的影响对一步法合成的溶胶-凝胶燃烧合成路线进行了研究。已经发现Cu作为烧结助剂非常活泼，显着降低了GDC烧成温度。观察到用少量的铜（0.5摩尔％）将温度降低了500°C，从而获得了具有显着离子电导率的致密体。经膨胀计分析后，在烧结温度1000-1200°C范围内，使用Rietveld精炼方法研究晶体结构，同时进行相对密度和显微组织检查。在最低的烧结温度下制造了高致密体，从而促进了Ce _0.8（1-x） Gd _0.2（1-x） Cu _x O _{[1.9（1-x）+ x]的形成。}固溶体，并且在晶界处没有富第二相或富集铜或偏析或铜。与纯GDC相比，在200-800°C的温度范围内，最高铜含量为2.23·10 ^-3 –9.19·10 ^-2 S cm ^-1时，总电导率有所提高。