本文以五氧化二钽、活性炭为主要原料,氟化钾为熔盐介质,通过碳热还原氮化法在氨气气氛下成功制备了氮化钽(Ta5N6)晶须。运用X射线衍射仪(XRD)、场发射扫描电子显微镜(FESEM)、透射电子显微镜(TEM)对合成产物的组成、结构和形貌进行了表征。研究了升温方式、氮化气氛、氮化时间和催化剂含量对产物形成的影响。当Ni与Ta2O5的摩尔比为0.1、氮化气氛为氨气(流量为300 mL/min)、氮化时间为6 h时制备的晶须形貌最佳,晶须直径80~250 nm,长为1~5 μm,晶须的生长机制为气-液-固(VLS)和气-固(VS)两种机理的混合机制。

In this study, tantalum nitride (Ta5N6) whiskers were successfully prepared by carbothermal reduction and nitridation method under amonia flow atmosphere, using tantalum oxide (Ta2O5) and active carbon as the main raw materials, potassium fluoride (KF) as the molten salt. The compositions, structures and morphology of the whiskers were characterized by X-ray diffraction (XRD), Field Emission Scanning Electron Microscopy (FESEM) and Transmission Electron Microscopy (TEM). The effects of heat mode, nitridation atmosphere, nitridation time and catalyst content on the formation of whiskers were investigated. The whiskers have the best morphology when the molar ratio of Ni/Ta=0.1, nitridation atmosphere is amonia (300 mL/min) and nitridation time is 6 h. The whiskers have diameters of 80-250 nm and lengths of 1-5 μm, and a combined mechanism of vapor-liquid-solid (VLS) and vapor-liquid (VS) is responsible for the growth of Ta5N6 whiskers.