Electrochemical and optical behavior of bis-imidazolium ionic liquids

POLY 108

Wooram Lee, wr1002@hanmail.net, Y Kim, J. Y. Kim, K. D Ahn, E Kim, and T. H. Kim. chemical engineering, Yonsei university, shinchon, Seoul, 420-514, South Korea
Room-temperature ionic liquids (RTILs), having bis-imidazolium salts were prepared with high ion conductivity as an electrolyte to control their emission properties. The absorption maximum band is appeared around at 365 nm and extended up to 600 nm. Compare to other mono-imidazolium salts, PEO200BIm-TFSI which is dicationic molecule, the absorption maximum band is shifted to longer wavelength and the profile is extended beyond 600 nm The neat bis-imidazloium salts showed wide electrochemical window up to + 3.0 V in a two electrode cell, besides spectral behavior were strongly dependent on the excitation wavelength. A fluorescence maximum for the PEO-based bis-imidazolium salt, PEO200BIm-TFSI, was observed at 450 nm when the excitation wavelength was 390 nm. Further characterizations of PEO200BIm-TFSI and its derivatives are in progress to explore their electrical and optical properties.