Abstract

Phase equilibria involving solid solutions in the Li–Eu–O system in an oxidizing, inert, and reducing atmospheres during annealing mixtures of various precursors subjected to preliminary mechanochemical activation at temperatures of 400–1100°C and partial pressures \({{P}_{{{{{\text{O}}}_{2}}}}}\) ~ 21 and 0.01 kPa and \({{P}_{{{{{\text{H}}}_{2}}}}}\) ~ 5 kPa have been studied by X-ray powder diffraction and thermogravimetry. The solubility of lithium in EuO has been first estimated, which is no less than 50–60%. For Eu₂O₃ and \({\text{LiE}}{{{\text{u}}}_{{\text{3}}}}{\text{O}}_{4}^{{}}\) , it is 30% of the total amount of cations. Along with LiEuO₂, the formation of crystalline mixed-valent (Eu^II + Eu^III) phases LiEu₃O₄ and Li₂Eu₅O₈ has been confirmed. The thermal behavior of solid solutions Eu_{1 – x}Li_xO_{1 – δ} based on europium monoxide and Li_{1 + y}Eu₃O_{4 – γ} in air has been studied. The concentration phase diagram of the Li–Eu–O system has been constructed.

中文翻译：

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Li-Eu-O 体系中涉及固溶体的相平衡

摘要

在 400–1100°C 温度和分压下对各种前驱体混合物进行初步机械化学活化的退火过程中，Li-Eu-O 体系中的固溶体在氧化、惰性和还原气氛中涉及相平衡 \({{P } _{{{{{\text{O}}}_{2}}}}}\) ~ 21 和 0.01 kPa 和\({{P}_{{{{{\text{H}}}_{ 2}}}}}\) ~ 5 kPa 已通过 X 射线粉末衍射和热重分析进行了研究。锂在EuO中的溶解度首先被估计，不低于50-60%。对于 Eu ₂ O ₃和\({\text{LiE}}{{{\text{u}}}_{{\text{3}}}}{\text{O}}_{4}^{{ }}\)，为阳离子总量的30%。与LiEuO ₂一起，已经确认了结晶混合价(Eu ^II + Eu ^III )相LiEu ₃ O ₄和Li ₂ Eu ₅ O ₈的形成。研究了基于一氧化铕和Li 1 _{+ y} Eu ₃ O _{4 – γ}的固溶体Eu _{1 – x} Li _x O _{1 – δ在空气中的热行为。}构建了 Li-Eu-O 体系的浓度相图。