Chemical vapor synthesis was used to prepare Nb nanopowders with NbCl5 vapor as a raw material and Na vapor as a reductant. Thermodynamic analysis indicated that Na had a strong ability to reduce NbCl5. X-ray diffraction (XRD), field emission scanning electron microscopy (FESEM) with energy dispersive spectrometry (EDS), and transmission electron microscopy (TEM) were used to analyze and characterize the product powders. These powders contained two phases: Nb and NaCl. Pure-phase Nb powders were synthesized by vacuum evaporation. The spherical Nb particles had an average size of 30 to 120 nm. In addition, the effects of operating conditions, such as the evaporation temperature, the reaction temperature, and the argon flow rate, on the Nb particle size were investigated.

中文翻译：

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氯化物钠热还原化学气相合成超细铌粉

以NbCl5蒸气为原料，Na蒸气为还原剂，采用化学气相合成法制备Nb纳米粉体。热力学分析表明，Na 具有很强的还原 NbCl5 的能力。X 射线衍射 (XRD)、场发射扫描电子显微镜 (FESEM) 与能量色散光谱 (EDS) 和透射电子显微镜 (TEM) 用于分析和表征产品粉末。这些粉末包含两相：Nb 和 NaCl。通过真空蒸发合成纯相铌粉。球形 Nb 颗粒的平均尺寸为 30 至 120 nm。此外，还研究了蒸发温度、反应温度和氩气流速等操作条件对 Nb 粒径的影响。