Gd-doped ceria electrolytes (GDC, 10 at.% Gd) were prepared using a eutectic mixture of Li and Na carbonates as sintering aid (NLC - 0, 1, 3 and 5 mol%), using two processing routes (ceramic and chemical). Structural and microstructural characterization provided no evidence for significant solubility of alkali metal cations in GDC. Materials sintered at 1100 °C/4 h were similar in densification (>95%) and microstructure to those obtained from a commercial powder sintered at 1500 °C/4 h. Impedance spectroscopy in air (200–600 °C) and as a function of oxygen partial pressure (from 0.21 to about 10⁻²⁵ atm, 600–750 °C) showed that the low temperature conductivity of materials prepared using chemical synthesis surpassed the conductivity of a commercial GDC due to higher grain boundary conductivity. The estimated n-type conductivity of materials with NLC was also slightly higher than for pure GDC. The role of sintering aid and processing routes is discussed taking into consideration decomposition and volatilization of alkali salts.

使用碳酸锂和碳酸钠的共晶混合物作为烧结助剂（NLC-0、1、3和5 mol％），采用两种加工路线（陶瓷和化学）制备掺的二氧化铈电解质（GDC，Gd为10 at。％） ）。结构和微观结构表征没有提供证据表明碱金属阳离子在GDC中具有显着的溶解性。在1100°C / 4 h烧结的材料的致密化（> 95％）和微观结构与从在1500°C / 4 h烧结的商业粉末获得的材料相似。空气中的阻抗谱（200–600°C）和氧分压的函数（从0.21到大约10 ^{− 25} atm，600–750°C）表明，由于较高的晶界电导率，使用化学合成方法制备的材料的低温电导率超过了商用GDC的电导率。使用NLC估算的材料的n型电导率也略高于纯GDC。考虑到碱金属盐的分解和挥发，讨论了烧结助剂和加工路线的作用。