Formation of submicron copper sulfide particles using spray pyrolysis method

The morphology and crystalline phase of submicron copper sulfide particles prepared by spray pyrolysis method have been studied. In a nitrogen gas atmosphere, the covellite phase (CuS) spherical particles could be prepared using the solution with molar ratio of copper nitrate to thiourea and furnace temperatures of 1:2 at 200-300 degrees C, as well as of 1:5 at 200-600 degrees C. The crystalline phase of particles was highly depended on the composition of the precursors and the pyrolysis temperature. The sphericity of particles could be enhanced by increasing the temperature and prolonging the residence time of the droplets or particles in the furnace.