Synthesis Of Ionic Liquids And Application In The Aluminum Secondary Battery

Organic-inorganic hybrid material is a new composite between organic and inorganic compound.Ionic liquids are composed of ions entirely, and have high conductivity, nonvolatile, no- nflammable, heat-stable, and show good solubility to many inorganic and organic substances. For their high conductivity and wide electrochemical window, they are widely used in electr- ochemical field as a green alternative solvent and electrolyte.The paper is based on the production of our predecessors. Firstly, six common ionic liq- uids were synthesised, including 1-propylpyridine bromide([Pr-Py]Br), 1-butylpyridine bro- mide([BuPy]Br), 1-propyl-2-methylpyridine bromide([Pr-2-MPy]Br), 1-butyl-2-methylpyri- dine bromide([Bu-2-MPy]Br), 1-propyl-4-methylpyridine bromide ([Pr-4-MPy]Br), 1-butyl- 4-methylpyridine bromide([Bu-4-MPy]Br), and then six tetrafluoroborate ionic liquids were synthesised, including 1-propylpyridine tetrafluoroborate([PrPy]BF4), 1-butyl pyridine te- trafluoroborate ([BuPy]BF4), 1-propyl-2-methylpyridine tetrafluoroborate([Pr-2-MPy]BF4), 1-butyl-2-methylyridine tetrafluoroborate([Bu-2-MPy]BF4), 1-propyl-4-methylpyridine tetr- afluoroborate ([Pr-4-MPy]BF4), 1-butyl-4-methylpyridine tetrafluoroborate([Bu-4-MPy]BF4), characterized by IR. these twelve ionic liquids were obtained. Their conductivity were tested. For their good conductivity, they can be used as conductive medium in the application of electrolyte.Two kinds of aluminum salts, tetrafluoroborate aluminum(Al(BF4)3) and trifluoromethyl sulfonic acid aluminum(Al(CF3SO3)3), were synthesised and characterized by IR.Two systems of organic-inorganic hybrid materials,aluminium salts(Al(BF4)3 and Al(CF3 SO3)3)-tetrafluoroborate ionic liquids and trifluoromethyl sulfonic acid aluminum-organic sol- vents,were prepared and the conductivity of such system were investigated The results indica- ted that these two types of hybrid materials have high conductivity, and it is possible that they can be applied to aluminum secondary battery. But they have their own advantage and disadv- antage. organic solvent-trifluoromethyl sulfonic acid aluminum hybrid material have low ma- terial price, simple operation, but organic solvent is volatile, non-heat-resistance. Ionic liquid- inorganic aluminum salt hybrid materials have high conductivity, low boiling point, but their material price are expensive.