Chemical synthesis and characterization of Zn-doped cadmium oxide based nanoparticles: As nanofluids for thermophysical applications

Semiconductor nanoparticles are studied worldwide at present because of their good optical, physical and chemical properties. In this research, a set of Zn doped cadmium oxide (Cd1-xZnxO1-?) nanoparticles were synthesized by simple chemical precipitation route. The precursor materials used in this work were cadmium nitrate and zinc nitrate (as basic materials) and sodium hydroxide (as a precipitator material). The formed hydroxides of Cd/Zn were washed with water and ethyl alcohol (9:1 v/v) and dried at 75o C overnight. The dried powder was then heat treated for 1 h each at 150, 300, 450o C, respectively and then cooled down to room temperature. The prepared nanoparticles were characterized by XRD where the peaks are well matched with the phase purity of cubic structure. FTIR analysis confirmed the presence of the functional groups present in the pure and Zn doped CdO nanoparticles. The SEM results showed that the obtained nanoparticles are polycrystalline in nature, having the average grain size of 100-200 nm. The molecular interactions with respect to the different dopant concentrations (Zn) and their thermo-physical characteristics of CdO based nanofluids (Cd1-xZnxO1-?; where x=0, 0.05, 0.10, 0.15 and 0.20) prepared in ethylene glycol were also studied and reported. It was found that the intermolecular free length of the present nanofluids seemed to be increasing with the higher incorporation of the Zn2+ ions in CdO nanoparticles.