Comparative study of the ion conductivities of substituted tetrabutylammonium salts (C 4 H 9 ) 4 N]BF 4 and [(C 4 H 9 ) 4 N]Br

The ion conductivity of the salts [(C4H9)4N]BF4 and [(C4H9)4N]Br was studied in vacuum at temperatures from room temperature to 190 and 135°C, respectively. The salts have phase transitions to disordered high-temperature phases accompanied by an increase in conductivity. [(C4H9)4N]Br has higher conductivity than [(C4H9)4N]BF4. As the conductivity decreases with the increasing size of the anion, the BF4 – and Br– anions are the most probable current carriers in the salts.