HETEROGENEOUS AND HOMOGENEOUS ELECTRON-TRANSFER REACTIONS OF TETRATHIAFULVALENE IN AMBIENT-TEMPERATURE CHLORALUMINATE MOLTEN-SALTS

The electrochemistry of tetrathiafulvalene (TTF) in an ambient tempera ture chloroaluminate molten salt composed of 1-ethyl-3-methylimidazoli um chloride mixed with AlCl3 has been examined. In both basic and acid ic melts TTF is oxidized in two consecutive, one-electron steps to TTF + and then to TTF2+. In basic melts, neutral TTF is stable and its oxi dations are well-behaved on the voltammetric time scale. TTF2+ is adso rbed at a glassy carbon working electrode in basic melts. Constant cur rent electrolysis of TTF to TTF+ at a Pt electrode in basic melt produ ces purple crystals which appear to be electronically conductive. In a cidic melts HCl, present as an impurity, oxidizes TTF to TTF+. Diffusi on coefficient measurements by pulse voltammetry suggest that TTF form s a slowly diffusing AlCl3 adduct in acidic melts.