Synthesis of Niobium Boride Nanoparticle by RF Thermal Plasma

Experimental study has been conducted to investigate the formation mechanism of transition metal boride nanoparticles in radio frequency thermal plasmas. The effect of nucleation temperature on the synthesis of niobium boride nanoparticles was investigated. The operating condition of powder feed rate plays an important role in the synthesis of boride nanoparticles. The mass fraction of niobium boride in the product was decreased with increasing powder feed rate. The main reason is that the evaporation time of niobium is long and the existence area of evaporated niobium is extended along with the thermal plasma flame at high powder feed rate. The diameter of the product increases along with the increase of powder feed rate due to increased monomer density in the plasma. In addition, high melting and boiling temperatures of niobium leads to high mass fraction over 96% of niobium boride in the collecting filter.