Synthesis of Zn_1-xCu_xO Nanoparticles by Coprecipitation and Their Structure and Electrical Property

The Zn_1-xCu_xO (x = 0 - 6% wt) nanoparticles has been synthesized by coprecipitation method using zinc acetate dihydrate, and copper powder were employed with HCl and NH₄OH respectively as solvent and precipitating agents. The effect of Cu concentration on structural, optical, and electrical properties of Zn_1-xCu_xO nanoparticles were investigated. The diffraction patterns of XRD indicate that Zn_1-xCu_xO phase crystallized in the wurtzite structure having crystal size which was evaluated by using MAUD software, in the range of 28 - 79 nm. Electron microscope analysis shows the morphology of Zn_1-xCu_xO is nanowires, having finer grains with the increasing content of Cu. The Cu doping reduced the optical band gap energy from 3.10 eV to 2.80 eV, while the electrical conductivity increased from 1.18 × 10^-8 to 24.25 × 10^-8 S/cm. This result implies that Cu⁺ or Cu²⁺ ions have substituted Zn²⁺ ions. However, doping of Cu more than 4% wt increase optical band gap which makes the electrical conductivity decrease. The electrical conductivity obtained from this study is significantly higher than that reported previously.