Electrosyntheses of free-standing and highly conducting polyselenophene films in an ionic liquid

The electrochemical polymerization of selenophene in a room temperature ionic liquid 1-butyl-3-methylimidazolium hexafluorophosphate (BmimPF6) led to the formation of free-standing and highly conducting polyselenophene (PSe) films with an electrical conductivity as high as 2.3 S/cm, higher than PSe electrodeposited in conventional media. The polymerization rate was significantly improved as BmimPF6 served as both the growth medium and an electrolyte. PSe showed good electroactivity and stability even in concentrated sulfuric acid. Infrared (IR) spectra confirmed the polymerization mainly through α–α′ coupling. Scanning electron microscopy results indicated the formation of smooth and compact PSe films.