Titanium dioxide/graphene oxide composite and its application as an anode material in non-flammable electrolyte based on ionic liquid and sulfolane

Abstract

A composite of aminosilane-grafted TiO 2 (TA) and graphene oxide (GO) was prepared via a hydrothermal process. The TiO 2 /graphene oxide-based (TA/GO) anode was investigated in an ionic liquid electrolyte (0.7 M lithium bis(trifluoromethanesulfonyl)imide (LiNTf 2 )) in ionic liquid (N-methyl-N-propylpyrrolidinium bis(trifluoromethanesulfonyl)imide (MPPyrNTf 2 )) at room temperature and in sulfolane (1 M lithium hexafluorophosphate (LiPF 6 ) in tetramethylene sulfolane (TMS)). Scanning and transmission electron microscopy (SEM and TEM) observations of the anode materials suggested that the electrochemical intercalation/deintercalation process in the ionic liquid electrolyte with vinylene carbonate (VC) leads to small changes on the surface of TA/GO particles. The addition of VC to the electrolyte (0.7 M LiNTf 2 in MPPyrNTf 2 + 10 wt.% VC) considerably increases the anode capacity. Electrodes were tested at different current regimes in the range 5-50 mA g . The decrease in anode capacity with increasing current rate was interpreted as the result of kinetic limits of electrode operation. A much lower capacity was observed for the system TA/GO│1 M LiPF 6 in TMS + 10 wt.% VC│Li.

Study of the Active Carbon from Used Coffee Grounds as the Active Material for a High-Temperature Stable Supercapacitor with Ionic-Liquid Electrolyte

“…Certain solutions can be application of Room Temperature Ionic Liquids RTIL [ 17 ]. They are non-flammable [ 18 ] and can be tested in specific applications by appropriate selection of cation and anion components [ 19 ]. Properly selected, in terms of electrochemical properties, ionic liquid should be characterized by high stability in the widest range of potentials, high ionic conductivity and a melting point below the required operating temperature of the supercapacitor.…”