Preparation and characterization of tungsten oxynitride nanowires

Tungsten oxynitride nanowires were generated by the reaction of ammonia with ultra-thin tungsten oxide nanowires which were themselves prepared by a simple solvo-thermal treatment of tungsten chloride in a cyclohexanol solvent. The resulting tungsten oxynitride nanowires exhibited a high specific surface area of 221 m2 g−1, even exceeding that of 151 m2 g−1 for the bundled and ultra-thin tungsten oxide nanowire precursor. The observed weak, temperature-independent paramagnetism indicates that the tungsten oxynitride nanowires are metallic, but no superconducting transition was observed above 2 K.