无机-有机杂化聚合物电解质的制备与电化学性能

PREPARATION AND ELECTROCHEMICAL PROPERTIES OF AN INORGANIC-ORGANIC HYBRID POLYMER ELECTROLYTE

以有机改性聚硅氧烷为单体加入液态电解质通过紫外光辐射固化制备了无机有机杂化聚合物电解质.含有丙烯酸酯端基的有机改性聚硅氧烷单体是通过正硅酸甲酯(TMOS)的水解缩合反应产物与丙烯酸2羟乙酯(HEA)进行脱甲醇反应合成的.它是一种多官能团单体,其结构通过核磁共振氢谱(1HNMR)分析、红外光谱(FTIR)分析及二氧化硅分析进行了表征,分子式可表达为SiO1.143(OH)0.016(OCH3)1.339(OCH2CH2OCOCHCH2)0.357.无机有机杂化聚合物电解质的电化学性能通过交流阻抗和循环伏安法进行了表征.其离子电导率随着液态电解质含量的增大而提高,当液态电解质含量为85wt%时,电导率在22℃为5.5×10-3Scm-1,在-23℃也能达到1.1×10-3Scm-1.界面电阻经过开始2天的增大后达到稳定,电化学稳定窗口超过5.0V,不锈钢电极上锂的电化学沉积与剥离循环可逆性很高.

An inorganic-organic hybrid polymer electrolyte based on organically modified polysiloxane was prepared by UV radiation curing in the presence of liquid electrolyte. The organically modified polysiloxane with acrylate groups at the terminal positions was synthesized by hydrolytic condensation of tetramethoxysilane and followed by ester exchange reaction using 2-hydroxyethyl acrylate. This monomer was polyfunctional with the rational formula of Si01.143 （ OH）0.016 （ OCH3 ） 1.339 （ OCH2 CH2OCOCH=CH2 ）0.357 obtained from ^1H-NMR analysis,FT-IR analysis and silica analysis .The electrochemical properties of the inorganic-organic hybrid polymer electrolyte were determined by ac impedance and cyclic voltammetry. Ionic conductivity was greatly enhanced with increasing amounts of liquid electrolyte. When the polymer electrolyte contained 85 wt% liquid electrolytes, the conductivity was around 5.5×10^-3 Scm^-1 at 22℃ and 1.1×10^-3 S cm^-1 even at - 23℃. Interface resistance increased initially and reached a steady value after 2 days. Oxidation stability was up to 5.0 V against the lithium reference electrode, and electrochemical plating/stripping of lithium on the stainless steel electrode was reversible.