Doping effect of Al on the yellow chromogenicity of V-doped ZrO₂

Abstract

In this study, the effect of Al addition on the yellowness of V-doped ZrO₂ was investigated. V-, Al-, and (V,Al)-doped as well as pure ZrO₂ powders were prepared via complex polymerization, and their thermally decomposed products were characterized. The absorption edge of the V-doped ZrO₂ exhibited a red shift as the heating temperature increased. In addition, the intensity of the absorption peaks centered at approximately 350 nm increased when Al was added to V-doped ZrO₂. The yellowness parameter b* increased significantly when V was added to ZrO₂; however, the addition of Al to ZrO₂ did not improve b*. When Al was added to V-doped ZrO₂, the b* value was significantly higher than that when only V was added, particularly after calcination at 700 °C. Furthermore, it was found that V in V- and (V,Al)-doped ZrO₂ was primarily present as V⁵⁺ and partially V⁴⁺ using X-ray photoelectron spectroscopy.