Synthesis And Conductive Properties Of ZnO By Hydrothermal Method

ZnO conductive powder has attracted attention for their unique properties andapplication in plastic, fiber and so on. Doping zinc oxide powder has excellentsemiconductor character and gives material efficient antistatic performance, withadvantages of light colour, good dispersion performance and low cost, etc.The synthesis of ZnO by hydrothermal method has been investigated in thisarticle. Al, Ga and Sn ions were doping into the ZnO. Finally, Ga doping of ZnO iscalculated by the first-principles, and study the conductive mechanism.The doped ZnO powder used nitrate and sodium hydroxide as main startingmaterial. X-Ray Diffraction (XRD), Scanning Electron Microscope (SEM), EnergyDispersive Spectrometer (EDS) and X-ray photoelectron spectroscopy (XPS) wereused to characterize structure and morphology of conductive powder, discussing therelations between conductive property and structure and morphology.The effects of technological parameters, such as doping content, hydrothermaltemperature and time, etc, on conductive property of doped ZnO powder wereanalysed and the optimal technological parameters were given as follows: under ahydrothermal temperature of150℃and keep warm in3hours, the conductivity of1.5%Al doped ZnO powder is2.2×10~6Ω·cm and its average particle size is42.52nm;The conductivity of2.0%Sn doped ZnO powder is5.24×10~5Ω·cm and its averageparticle size is23.28nm. The conductivity of1.8%Ga doped ZnO powder is2.18×10~6Ω·cm and its average particle size is22.42nm.Calculating the lattice constant, the band structure and density of states of pureZnO by Castep software, the lattice constant is in accordance with experimental data.The results of calculation of the band structure and density of states show that idealZnO is a semiconductor material and the band gap is1.49eV.Calculating the bandstructure and density of states of Ga doped-ZnO in two different cases, the resultsshowed that the electronic structure of ZnO is changed after doped with Ga, makingFermi level enter into the conduction band. So it became n-type semiconductor withgood conductive performance.