Room-Temperature Ionic Liquid. A New Medium for Material Production and Analyses under Vacuum Conditions

A characteristic of negligible vapor pressure that a room temperature ionic liquid (RTIL) possesses enables us to introduce RTILs in the apparatus requiring vacuum conditions for material production and analyses. This combination creates a path toward development of new techniques under vacuum conditions. As for material production especially metal nanoparticle synthesis, those are magnetron sputtering onto TRILs, plasma reduction in RTILs, physical vapor deposition onto RTILs, and electron beam and g-ray irradiation to RTILs. Interestingly the nanoparticles prepared in RTILs without any stabilizing agent do not aggregate in the RTILs. Also, we can introduce RTILs in analytical instruments requiring vacuum conditions such as X-ray photospectroscopy (XPS), matrix-assisted laser desorption/ionization mass spectroscopy (MALDI, MS), scanning electron microscopy (SEM), and transmission electron microscopy (TEM). The fact that the RTIL is not charged under irradiation by quantum beams enables us to establish new analytical techniques. Furthermore, homogeneous conditions that are obtainable by dissolving a substance in a RTIL are quite useful for conducting analyses using the instruments described above for example MALDI-MS with high reproducibility.