Synthesis of Cd1−xZnxS nanoparticles by a novel thermal decomposition approach and studies on their optical properties

Cd1−xZnxS nanoparticles (x = 0–1.0) have been synthesized via a facile thermal decomposition approach using cadmium acetate, zinc acetate and thiourea at 200 °C in diphenyl ether. The structural, morphological, compositional and optical properties of the Cd1−xZnxS nanoparticles have been investigated by powder X-ray diffraction, field emission scanning electron microscopy, energy dispersive X-ray analysis, transmission electron microscopy, diffuse reflectance spectroscopy and photoluminescence spectroscopy. Solid solutions are formed at lower concentration of zinc (x ≤ 0.6) while phase separation occurs at higher concentration of zinc (x > 0.6) The crystallite size of Cd1−xZnxS nanoparticles lies in the range 3.9–5 nm and the energy dispersive X-ray analysis reveals uniform distribution of zinc, cadmium and sulfur in the solid solutions. The band gap of Cd1−xZnxS nanoparticles is tunable and the band gap varies from 2.36 to 2.99 eV.