Low-temperature synthesis of K2Ta2O3F6

► K2Ta2O3F6 can be obtained by fluorination reaction at 300 °C. ► The intermediates are assumed to be (NH4)2KTaOF6 and NH4KTaF7. ► Their thermal decomposition resulted in KTaF6. ► Hydrolysis of KTaF6 produces K2Ta2O3F6.