Structural and electrical properties of V-doped ZnO prepared by the solid state reaction

This paper reports the synthesis, crystal structure and electrical conductivity properties of vanadium (V)-doped zinc oxide (ZnO) powders (i.e. Zn1-2X V (X) O binary system, x = 0, 0.0025, 0.005, 0.0075 and in the range 0.01 a parts per thousand currency sign x a parts per thousand currency sign 0.15). I-phase samples, which were indexed as single phase with a hexagonal (wurtzite) structure in the V-doped ZnO binary system, were determined by X-ray diffraction (XRD). The limit solubility of V in the ZnO lattice at this temperature is 3 mol % at 950 A degrees C. The impurity phase at 950 A degrees C was determined as ZnV2O6 when compared with standart XRD data. The research focused on single I-phase ZnO samples which were synthesized at 950 A degrees C because of the limit of the solubility range is widest at this temperature. It was observed that the lattice parameters a and c decreased with V doping concentration. The electrical conductivity of the pure ZnO and single I-phase samples were studied using the four-point probe dc method at temperatures between 100 and 950 A degrees C in an air atmosphere. The electrical conductivity values of pure ZnO and 3 mol % V-doped ZnO samples at 100 A degrees C were 2.75 x 10(-6) and 7.94 x 10(-5) Omega(-1) cm(-1), and at 950 A degrees C they were 3.4 and 54.95 Omega(-1) cm(-1), respectively. In other words, the electrical conductivity increased with V doping concentration.