Formation of CdS nanoparticles by gas-diffusion method in sol–gel derived ureasilicate matrix

CdS nanoparticles (NPs) were prepared by exposing a hybrid ureasilicate gel containing cadmium (II) ions to H2S gas at room temperature. Additional component (tetraethoxysilane) was introduced during the synthesis in order to improve the mechanical properties of the host matrix. The obtained material was subsequently subjected to an annealing treatment under an argon atmosphere at temperatures that varied from 43 to 102 °C. The size of the embedded NPs increased with thermal annealing. The optical absorption spectroscopy, photoluminescence (PL) and transmission electron microscopy (TEM) measurements confirmed the formation of CdS nanoparticles (NPs) exhibiting quantum confinement effect.