Synthesis of Ni ₃S ₂ and NiSe nanoparticles encapsulated in carbon shell and coating these onto stainless steel surfaces by RAPET

Nickel sulfide and nickel selenide nanoparticles encapsulated in carbon shells are synthesized by the thermal decomposition of mixtures of nickel acetate and sulfur or selenium via a RAPET (Reaction under Autogenic Pressure at Elevated Temperatures) technique at 750°C for 3 h. The synthesized products are systematically characterized by powder X-ray diffraction (PXRD), scanning electron microscopy (SEM), and the encapsulation of Ni ₃S ₂ and NiSe nanoparticles by a carbon shell is confirmed by transmission electron micrographs (TEM). Such materials have pausible applications in photo voltaic devices, magnetic devices, in catalysis and as electrodes for batteries. Coated carbon on the surface of Ni ₃S ₂ and NiSe nanocrystals acts as a protective layer, making them thermally as well as chemically stable. Additionally, the possibility of coating a pristine stainless steel plate with Ni ₃S ₂-C core-shell composite layers is also demonstrated.