Extremely Low Temperature Crystallization in the A2M3O12 Family of Negative Thermal Expansion Materials

Abstract A 2 M 3 O 12 materials (A = Al, Sc, Fe, In, Ga, Y; M = Mo, W) were synthesized using the non‐hydrolytic sol‐gel process. In contrast to previous studies, in which amorphous materials were recovered that required heating to 500–700 °C to induce crystallization, several compounds could be crystallized in a temperature range compatible with low temperature processing of devices and composites. Under certain reaction conditions, crystalline Sc 2 Mo 3 O 12 , Fe 2 Mo 3 O 12 , and In 2 Mo 3 O 12 were obtained at temperatures as low as 230 °C. This may allow use of these materials for in‐situ composite formation, which could result in new practical applications.