Preparation and characterization of (V1−xAlx)2O3 ultrafine powders by chemical doping method

(V1−xAlx)2O3 ultrafine powders have been synthesized successfully by pyrolysizing poly-crystalline Al-doped precursor, Al-doped (NH4)5[(VO)6(CO3)4(OH)9]·10H2O in H2 atmosphere at 1373 K for the first time. The relation between the ratio of Al/V in the VOCl2 solution and that in polycrystalline Al-doped precursor was studied. The result shows that this chemical doping method is successful, and the Al (III) content in precursor is controllable. The lattice parameters of (V1−xAlx)2O3 determined by XRD at room temperature and high-temperature reveal that the Al (III) enter the V2O3 lattice. The SEM micrograph shows that the size of the powder particles is about 100–200 nm. The DSC and magnetic susceptibility results of the (V1−xAlx)2O3 demonstrate that the powders exhibit the intrinsic phase transition properties.