三维结构聚丙烯酰胺/聚乙烯醇水凝胶的合成及其在超级电容器中的应用

分别以过硫酸铵(APS)和N-N二甲基双丙烯酰胺(NMBA)作为引发剂和交联剂引发交联具有三维网络结构的聚丙烯酰胺/聚乙烯醇(PAM-PVA)水凝胶,将该水凝胶浸泡在6mol/L的KOH溶液中不同时间,制备凝胶聚合物电解质,并组装成双电层超级电容器。采用循环伏安、恒流充放电、交流阻抗等电化学测试技术对组装的超级电容器进行全面的性能研究,采用蓝电监测系统测试组装的超级电容器的稳定性。结果表明,以2.0g聚乙烯醇和10.0g丙烯酰胺反应制得的凝胶基体在吸收72h电解质溶液后组装的超级电容器性能最优,其比电容可达230F·g~(-1),5 000次充放电之后其循环保持率仍高达98%。

Synthesis of Three-dimensional Polyacrylamide/Poly(vinyl alcohol) Hydrogel and Its Application in Supercapacitor

The polyacrylamide/poly(vinyl alcohol) (PAM-PVA) hydrogels with three-dimensional network structure were synthesized, taking ammonium persulfate (APS) and N-N dimethylbisacrylamide (NMBA) as initiators and crosslinkers, respectively. The gel polymer electrolyte was prepared by immersing the obtained hydrogel in 6 mol/L KOH solution for different duration, and the gel polymer electrolyte was adopted to assemble supercapacitor. The electrochemical performance of the assembled supercapacitor was studied by electrochemical techniques including cyclic voltammetry, constant current charge-discharge and AC impedance. The stability of the assembled supercapacitor was evaluated by blue electric monitoring system. The results showed that the supercapacitor with the best performance was prepared via the gel polymer electrolyte obtained from the reaction of 2.0 g PVA with 10.0 g acrylamide and further 72 h electrolyte solution absorption. Its specific capacitance can reach 230 F/g and the capacitance retention rate kept 98% after 5 000 cycles.