Due to the polymer plasticizing ability and ionic nature of ionic liquids (bistrifluoromethanesulfonimidate salts of 1-butyl-2,3-dimethylimidazolium and dodecylethyldiphenylphosphonium, BDMIm Tf 2 N and DEDPP Tf 2 N, respectively), they were found to be excellent compounds for preparing ion-selective membrane electrodes. Membrane polymers studied were poly(methyl methacrylate) and poly(vinyl chloride). The electrodes demonstrated good and extremely stable response to both cations and anions (including surfactants) and were successfully applied to the analysis of detergents.
4-methyl-2- [(2,2,3,3,4,4,5,5-octafluoropentyl)oxy]-1,3,2-dioxaphosphinane with the oxidation number of phosphorous (III) is used as an oxidative additive (OA) to a standard carbonate-based electrolyte for the high-voltage Li-ion cells with the overlithiated layered oxide Li 1.20 Ni 0.18 Mn 0.53 Co 0.09 O 2 (OLO) as a positive electrode. Electrochemical stability of electrolytes with and without OA is compared by linear sweep voltammetry, and characteristics of coin half and full cells are examined by means of cycling tests and electrochemical impedance spectroscopy. Presence of OA in electrolyte mixture provides noticeable improvement in Coulombic efficiency, capacity retention, and rate properties of the cells, most likely, through the formation of an interface layer on the OLOsurface due to the decomposition of OA. Morphology of OLO after cycling with OA-containing electrolyte is investigated by scanning electron microscopy and the presence of amorphous coating is observed; 31 P NMR analysis reveals that the products by the oxidation of OA are present on the cathode's surface. Differential scanning calorimetry data point out the substantially improved thermal stability of the OLO cathode after cycling in OA-containing electrolyte. Therefore, substituted dioxaphosphinanes may be considered as a promising structural pattern for design of new additives for the development of high-voltage electrolytes.
scite is a Brooklyn-based organization that helps researchers better discover and understand research articles through Smart Citations–citations that display the context of the citation and describe whether the article provides supporting or contrasting evidence. scite is used by students and researchers from around the world and is funded in part by the National Science Foundation and the National Institute on Drug Abuse of the National Institutes of Health.