Sol-gel preparation of CdS_xSe_1−x solid solution microcrystal-doped glasses

Abstract

CdS_xSe_1−x solid solution microcrystal-doped glasses with a significant quantum-sized effect were prepared by the sol-gel process. Gels synthesized by the hydrolysis of complex solution of Si(OC₂H₅)₄, Cd(CH₃COO)₂·2H₂O and selenium were treated in H₂S and hydrogen gas atmospheres to form CdS_xSe_1−x solid solution crystals, whose compositions were determined from the X-ray diffraction and Raman scattering spectra. Sulphur in CdS crystals is substituted for selenium by heating in hydrogen gas, and its content decreases with increasing temperature. On the other hand, the sulphur content increases on reacting the CdSe crystalprecipitated glasses with H₂S gas. The optical absorption spectra are shifted towards the red as the crystal size increases, and the gap energy is reciprocally proportional to the square of the crystal size.