RAPET (Reaction under Autogenic Pressure at Elevated Temperatures) Technique Assisted Synthesis of Encapsulated CdE@C [E = S, Se and Te] Nanocrystallites

We present an easy synthetic method for the fabrication of encapsulated nanosized semiconductor CdE [E = S, Se and Te] within the core of carbon capsule. We also discuss the growth of CdSC and neat CdS nanocrystals on stainless steel coupons (SSC) by a reaction under autogenic pressure at elevated temperature (RAPET) technique. The thermal decomposition of mixture of Cd(acetate)₂ and sulfur, selenium and tellurium was carried out at 750°C under air for 3h. The synthesized products were systematically characterized by X-ray powder diffraction, scanning electron microscopy (SEM) and transmission electron microscopy. Carbon matrix, with an average diameter of 250nm, encapsulated several nanometric-sized CdS nanocrystals, as evidenced from high resolution SEM (HRSEM). We examined the optical properties of this core/shell CdS@C and nonencapsulated CdS nanocrystals and found that both core shell and neat CdS nanocrystals show emission in the pohotoluminescence (PL) spectrum.