In this work new RP materials of the La_2-xGd_xNiO_4+δ series were synthesized and their structural features, oxygen stoichiometry and transport properties were studied by X-ray diffraction, TGA, mass relaxation method and oxygen isotope exchange with C¹⁸O₂ in a flow reactor. According to XRD data, La_2-xGd_xNiO_4+δ (x = 0.0; 0.2; 0.4) are single-phase samples with a tetragonal structure. Doping with Gd resulted only in the insignificant increase of the interstitial oxygen content (δ changes in the range of 0.13–0.15). A high oxygen mobility was demonstrated: at 700 °C D_chem ~ 10⁻⁵ cm²/s (mass relaxation data) and self–diffusion coefficient D^⁎ ~ 10⁻⁸ cm²/s (oxygen isotope exchange data). Such characteristics are determined by the cooperative mechanism of oxygen migration involving both regular and highly-mobile interstitial oxygen. Gd doping, however, resulted in non-uniformity of the oxygen migration routes. To describe this feature, a mathematical model has been developed including a slow exchange between neighboring oxide anions. Oxygen mobility decreases with increasing Gd content.

在这项工作中，合成了La _2-x Gd _x NiO _{4 +δ}系列的新型RP材料，并通过X射线衍射，TGA，质量弛豫方法和与C进行氧同位素交换研究了它们的结构特征，氧化学计量和传输性质。在流动反应器中为¹⁸ O ₂。根据XRD数据，La _2-x Gd _x NiO _{4 +δ}（x  = 0.0; 0.2; 0.4）是具有四方结构的单相样品。掺杂Gd仅导致间隙氧含量的增加不明显（δ在0.13–0.15范围内变化）。氧迁移率高：在700°C D_化学 〜10 ^-5 厘米² /秒（质量松弛数据）和自扩散系数d ^⁎  〜10 ^-8 厘米² /秒（氧同位素交换的数据）。这些特性是由涉及规则和高度移动的间隙氧的氧迁移的协同机制决定的。但是，Gd掺杂会导致氧气迁移路径不均匀。为了描述此功能，已经开发了一种数学模型，其中包括相邻氧化物阴离子之间的缓慢交换。氧气迁移率随Gd含量的增加而降低。