PVA-KOH-TiO_2-H_2O复合碱性固态聚合物电解质

Alkaline solid polymer electrolytes based on PVA-KOH-TiO_2-H_2O

以聚乙烯醇(PVA)与二氧化钛(TiO2)和氢氧化钾(KOH)为原料,运用溶液浇铸法制备PVA-KOH-TiO2-H2O复合碱性聚合物电解质(ASPE)。以X射线衍射(XRD)、差热扫描(DSC)、扫描电镜(SEM)、循环伏安(CV)和交流阻抗法(AC)对复合膜的结构和性能进行表征。XRD和DSC分析表明TiO2的加入可以增加PVA基体的无定形比例。PVA-KOH-TiO2-H2O ASPE显示了良好的电化学性能,水含量为50%,室温(20℃)离子电导率在0.102～0.171S/cm之间;以不锈钢为阻塞电极测得膜的电化学稳定窗口为±1.2V。以PVA-KOH-TiO2-H2O ASPE组装的固态聚合物电解质电容器首次放电比电容为44F/g,1000次循环后比电容为33F/g,其恒流充放电、循环伏安、交流阻抗测试均显示了良好的电容性能。

A novel composite alkaline solid polymer electrolyte （ASPE） composed of PVA polymer matrix with TiO2 ceramic fillers, KOH and H2O, was prepared by a solution casting method. The characteristic properties of alkaline PVA-KOH-TiO2-H2O polymer electrolyte films were studied by XRD, DSC, SEM, cyclic voltammetry and AC impedance method. It is found that the addition of TiO2 filler into PVA polymer matrix augments the domain of amorphous region. The alkaline polymer electrolyte blended with TiO2 ceramic fillers shows excellent electrochemical properties： the room temperature （20 ℃） ionic conductivity value is 0.102-0.171 S/cm at film water content of 50%, the electrochemical stability window at the metal- electrolyte interface is of ± 1.2 V for stainless steel electrode. The application of alkaline PVA-KOH -TiO2-H2O ASPE to supercapacitor was also investigated. The specific capacitance of ASPE supercapacitor is 44 F/g at the first time, and decreases to 33 F/g after 1 000 cycles. The ASPE supercapacitor demonstrates excellent properties by Galvanostatic charging and discharging, cyclic voltammetry and AC impedance.