Chemical Vapor Synthesis of Ultrafine Niobium Powder Via Sodiothermic Reduction of Chloride

Chemical vapor synthesis was used to prepare Nb nanopowders with NbCl 5 vapor as a raw material and Na vapor as a reductant. Thermodynamic analysis indicated that Na had a strong ability to reduce NbCl 5 . 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.