Low-temperature synthesis of ultrafine Cr,Mg-codoped Al2TiO5 nanocrystals as high-temperature green ceramic pigment.

Tialite (Al 2 TiO 5) is attracting as a high-temperature ceramic host matrix, but the decomposition of Al 2 TiO 5 at 780–1280 °C is a serious obstacle for practical application. Herein we prepared successfully ultrafine Cr,Mg-codoped Al 2 TiO 5 green ceramic pigment with the nanocrystal sizes less than 50 nm and high-temperature stability of up to 1200 °C via nonhydrolytic sol-gel (NHSG) method followed by heating treatment of 750 °C. The effects of Cr and Mg content on phase composition, crystal structure, thermal stability and color property were well investigated. The optimum Cr,Mg-codoped Al 2 TiO 5 pigment with 20 mol% Mg and 6 mol% Cr exhibited an excellent green color (L* = 76.94, a* = −9.62, b* = 14.17), which can be reasonably maintained in exposed air by a heating treatment at 1200 °C for 10 h or in transparent ceramic glaze at 1200 °C for 30 min. These enhanced performances were mainly attributed to synergistic effect of Cr and Mg doping, which hindered the tendency of Al 2 TiO 5 toward decomposition, indicative of its potential application in high-temperature ceramic decoration. [ABSTRACT FROM AUTHOR]