Vapor phase preparation and properties of NbN/C(carbon coils)/NbN-NbN micro-coils/micro-tubes

NbN/C(carbon coils)/NbN composite micro-coils/micro-tubes and pure NbN micro-coils/micro-tubes were prepared by a vapor phase diffusion treatment (niobinizing and nitriding) of the regularly coiled carbon micro-coils. The preparation conditions, morphologies and some properties of the micro-coils/micro-tubes were examined. The carbon coils were completely converted to the NbN micro-coils/micro-tubes by treatment at 1200 °C for 3 h. The bulk electrical resistivity and specific surface area of the NbN micro-coils/micro-tubes were 0.03-0.05 Ω cm and 5-20 m2/g, respectively.