Reduction behavior of tungsten oxide with and without scandia doping.

As an important powder material for scandate cathode, Sc₂O₃-doped WO₃ powder together with hollow spherical WO₃ for comparison was prepared by spray-drying method. The reduction behavior and kinetics of pure WO₃ and Sc₂O₃-doped WO₃ were studied by temperature-programmed reduction (TPR) method. It is found that scandia doping can decrease the reduction activation energy of WO₃ and thus lower the reduction temperature and increase the reduction rate. Based on the kinetics results, the reduction techniques are presented. The obtained powder has a narrow size distribution in the range of 0.6–0.8 μm. [ABSTRACT FROM AUTHOR]