The high‐temperature phase of β‐Cu₂Se always appears as the major phase for the reaction carried out using chemical solution methods. Here, a procedure was developed that could fabricate a single phase of α‐Cu₂Se_1−xTe_x (x=0.02 and 0.04) by room‐temperature aqueous synthesis using NaBH₄ as reducing agent followed by cold pressing and sintering at 650 °C for 6 h in a flowing gas mixture of 20 % H₂ and 80 % N₂. The energy‐efficient synthesis carried out at room temperature abides by the 6th principle for green chemistry with less energy consumption. The reaction mechanism was studied, and evidence was provided of α‐Cu₂Se being formed via the reaction between elemental Cu and Se atoms at room temperature. The resulting materials were characterized by powder X‐ray diffraction, field‐emission scanning electron microscopy, thermoelectric transport measurements, and Hall measurements. Cu_1.96Se_0.96Te_0.04 had the highest power factor of 11 μW cm⁻¹ K⁻² at 818 K, and Cu₂Se_0.96Te_0.04 had the maximum zT≥1.4 at T≥920 K among this series of materials.

中文翻译：

---

α-Cu2-ySe1-xTex的高能效合成和高热电性能

β-Cu的高温相₂硒始终显示为用于该反应的主要阶段进行了使用化学溶液的方法。这里，一个程序的开发，可以制造α-Cu构成的单相₂硒_{1- X}碲_X（X = 0.02和0.04），通过使用硼氢化钠室温含水合成₄如随后冷压和在650烧结还原剂在20％H ₂和80％N _2的混合气体中，在室温下放置6小时。在室温下进行的高能效合成遵循第六条绿色化学原理，能耗更低。研究了反应机理，并提供了α-Cu的证据在室温下，通过元素Cu和Se原子之间的反应形成₂ Se。所得材料通过粉末X射线衍射，场发射扫描电子显微镜，热电传输测量和霍尔测量进行表征。铜_1.96硒_0.96碲_0.04有11μW厘米的最高功率因子^-1 ķ ^-2在818 K，和Cu ₂硒_0.96碲_0.04有最大的zT在≥1.4 Ť这一系列的材料中≥920ķ。