Self-propagating high-temperature synthesis of potassium hexatitanate whiskers

摘要

Potassium hexatitanate (K2Ti6O13) whiskers with high thermal insulating capacity, good mechanical properties, and excellent chemical stability are promising functional materials. In this study, K2Ti6O13 whiskers were successfully prepared by one-step self-propagating high-temperature synthesis (SHS) method for the first time. Titanium dioxide (TiO2), potassium carbonate (K2CO3) and combustion accelerant with different molar ratios were mixed, and the combustion synthesis was performed using the oxygen bomb calorimeter. The effects of molar ratio TiO2 to K2CO3, the type and the amount of combustion accelerant on the purity and morphology of products were investigated by SEM and XRD. The results showed that uniformly distributed K2Ti6O13 whiskers. with high purity, good crystallinity, and morphology were obtained when the molar ratio of TiO2 to K2CO3 and the mass ratio of benzoic acid to (TiO2+K2CO(3)) were 4 and 2, respectively. K2Ti6O13 whiskers of length 10 gm and 1 mu m in diameter were obtained within 15 min. In addition, the benzoic acid was a better combustion accelerant than the starch and acetylene black.