Ionic liquids are basically molten salts. Furthermore, unlike many room temperature liquids, ionic liquids do not vaporize easily and are stable at high temperatures, along with other useful properties that make them unique and well suited for numerous applications. One of the most powerful applications of ionic liquids is in supercapacitors, which have very high electrical power density and long life. By using ionic liquids instead of conventional electrolytes in supercapacitors one can increase their energy density substantially. Unfortunately, still little is known about the fundamental reasons why some ionic liquids perform better than others. Studying the electronic structure of ionic liquids can shed light on this question and it will be possible to select the best ionic liquids for applications.
The first scientific article has been published based on results from the Estonian-Finnish beamline FinEstBeAMS. In this research paper, electronic structure of ionic liquids based on the [TFSI] anions was under investigation: valence band of [EMIM][TFSI], [DEME][TFSI] and [PYR1,4][TFSI] gas-phase ion pairs have been investigated using ultraviolet photoelectron spectroscopy (UPS). The photoelectron spectra have been interpreted by using different density functional and ab initio calculation methods. The leading authors of this article are Ivar Kuusik and Vambola Kisand from the Institute of Physics of the University of Tartu.
Read the paper here.
The electronic structure of ionic liquids based on the TFSI anion: A gas phase UPS and DFT study
Ivar Kuusik, Mati Kook, Rainer Pärna, Antti Kivimäki, Tanel Käämbre, Liis Reisberg, Arvo Kikas, Vambola Kisand
Journal of Molecular Liquids, Volume 294, 15 November 2019, 111580