制备了高氯酸锂(LiClO4)与1,3-氮氧杂环-戊-2-酮(ozo)形成的二元熔盐电解质,虽然先导物具有较高的熔点,但二者可形成均一、稳定的共熔体系,测试结果表明该熔盐体系具有低的共熔温度(-5O℃).红外光谱分析表明OZO通过Li—O键与LiClO4中Li^+配位而破坏了LiClO4的离子键,形成很大的配位阳离子,削弱了阴阳离子间的库伦作用力;同时Li—O配位也导致OZO分子间的氢键断裂,因而体系的共熔温度较之纯物质熔点显著降低,部分样品室温下以液体状态稳定存在.采用交流阻抗法和循环伏安法对其电化学性质进行研究,结果显示,配比n(LiClO4):n(OZO)=1:4.5的样品室温(25℃)电导率为O.66×10^-3S·cm^-1,80℃电导率为7.33×10^-3S·cm^-1;其电化学稳定电位窗口约为3.5V.
Novel binary molten salt electrolytes based on LiClO4 and 2-oxazolidinone (OZO) were prepared. The electrolytes appeared as liquid at room temperature though they were composed of two solids. DSC analysis showed that the LiClO4-OZO electrolyte was liquid with a eutectic temperature about -50 ℃. FTIR spectroscopy indicated that OZO could coordinate with Li^+ cation in the LiClO4-OZO system through Li-O bonding. A big coordinate cation was formed and the coulombic force was weakened. Meanwhile, Li-O coordination could also lead to the breakage of hydrogen bonding between OZO molecules, resulting in the decrease of the eutectic temperature of the system compared with pure salt. Some the molten salt samples existed as liquid state at room temperature. The electrochemical properties were evaluated by ac impedance spectroscopy and cyclic voltammertry, respectively. The conductivity of LiClO4-OZO electrolyte at molar ratio of 1:4.5 was 0.66×10^-3 S·cm^-1 at 25 ℃ and 7.32×10^-3 S· cm^-1 at 80 ℃, and the electrochemical window was about 3.5 V.