Kim Young-Deok, Jo Yun-Kyung, Jo Nam-Ju
Department of Polymer Science and Engineering, Pusan National University, Busan 609-735, Korea.
J Nanosci Nanotechnol. 2012 Apr;12(4):3529-33. doi: 10.1166/jnn.2012.5553.
Solid polymer electrolytes (SPEs) are an excellent alternative to liquid electrolytes due to their non-volatility, low toxicity, and high energy density. In this study, a SPE having the ion transport mechanism decoupled from segmental motion of a polymer based on poly(vinyl alcohol) (PVA) containing the salt lithium trifluoromethane sulfonate (LiCF3SO3, LiTf) has been prepared to overcome the low ionic conductivity of traditional SPEs at room temperature. PVA has a high glass transition temperature (358 K) and good mechanical properties, and despite being atactic, it can crystallize, especially if highly hydrolyzed. From an ac impedance analysis, it was found that the ionic conductivity of the PVA-based SPE increased with increasing salt concentration. In particular, a dramatic increase was observed between 40 and 50 wt% of salt. The ionic conduction mechanism of the PVA-based SPE is proposed based on intensive study using FT-IR spectroscopic measurements, XRD and AFM. Through measurements of linear sweep voltammetry (LSV) and cyclic voltammetry (CV), it is also found that the SPE with PVA and LiCF3SO3 has good electrochemical stability.
固体聚合物电解质（SPEs）由于其不挥发性、低毒性和高能量密度，是液体电解质的极佳替代品。在本研究中，为了克服传统SPEs在室温下离子电导率低的问题，制备了一种离子传输机制与基于含有三氟甲烷磺酸锂（LiCF3SO3，LiTf）的聚（乙烯醇）（PVA）的聚合物链段运动解耦的SPE。PVA具有高玻璃化转变温度（358K）和良好的机械性能，尽管它是无规立构的，但它可以结晶，特别是如果高度水解的话。通过交流阻抗分析发现，基于PVA的SPE的离子电导率随盐浓度的增加而增加。特别是，在盐含量为40至50 wt%之间观察到显著增加。基于使用傅里叶变换红外光谱测量、X射线衍射和原子力显微镜的深入研究，提出了基于PVA的SPE的离子传导机制。通过线性扫描伏安法（LSV）和循环伏安法（CV）测量，还发现含有PVA和LiCF3SO3的SPE具有良好的电化学稳定性。
