Understanding mass transfer mechanisms is vital for developing new material synthesis and densification technologies. Ion transport, serving both mass and charge transfer, is essential for the rapid preparation of high-performance fast ionic conductor thermoelectric materials like Zn₄Sb₃ and Cu₂Q (Q = S, Se). In the case of dual-cation fast ion conductor materials like CuAgSe, exploring the relationship between cation transport becomes pertinent. In this study, copper (Cu) and selenium (Se) undergo a reaction in the presence of an electric field (∼15 A), resulting in the formation of the CuSe compound. Subsequent to this initial reaction, a subsequent thermal environment facilitates the interaction among Cu, CuSe, and Ag₂Se, culminating in the rapid formation and densification of CuAgSe (with a relative density exceeding 99%) in just 30 s. Evidently, the diffusion of copper ions substantiates a pivotal role in facilitating mass transfer. As a result, CuAg_1+xSe samples with different silver contents (x = 0.01, 0.02, 0.03, 0.04 and 0.05) can effectively inhibit cation vacancy, and introduce highly ordered Ag nanotwins to enhance the electrical transport performance. For CuAg_1.04Se, a peak ZT value of 1.0 can be achieved at 673 K, which is comparable to the literatures. This work will guide the future electric field-assisted rapid mass transfer of materials.

中文翻译：

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双阳离子 CuAgSe 基材料：合成中的快速传质和高热电性能的实现

了解传质机制对于开发新材料合成和致密化技术至关重要。离子传输同时服务于质量和电荷传输，对于快速制备高性能快速离子导体热电材料如Zn ₄ Sb ₃和Cu ₂ Q (Q = S, Se) 至关重要。对于像 CuAgSe 这样的双阳离子快离子导体材料，探索阳离子传输之间的关系变得有意义。在这项研究中，铜 (Cu) 和硒 (Se) 在电场 (∼15 A) 下发生反应，形成 CuSe 化合物。在此初始反应之后，随后的热环境促进了 Cu、CuSe 和 Ag ₂ Se 之间的相互作用，最终在短短 30 秒内快速形成和致密化 CuAgSe（相对密度超过 99%）。显然，铜离子的扩散在促进传质方面发挥着关键作用。结果，不同银含量（x = 0.01、0.02、0.03、0.04和0.05）的CuAg _{1+ x} Se样品可以有效抑制阳离子空位，并引入高度有序的Ag纳米孪晶以增强电传输性能。对于 CuAg _1.04 Se，在 673 K 时可以达到 1.0 的峰值 ZT 值，与文献相当。这项工作将指导未来电场辅助材料的快速传质。