基于Co3O4/C复合水凝胶的全固态柔性超级电容器的研究

Construction of all-solid-state flexible supercapacitor based on Co3O4/C-incorporated hydrogel

以沸石咪唑骨架-67(ZIF-67)为前驱体,采用两步煅烧法制备了四氧化三钴/碳(Co3O4/C)纳米复合材料。利用自由基聚合法合成了Co3O4/C-聚丙烯酰胺水凝胶,进一步在水凝胶框架中原位聚合电化学活性聚吡咯颗粒,制备具有优异机械性能的柔性复合电极材料。在此基础上,将该柔性电极材料和水凝胶电解质组装成全固态柔性超级电容器;实验结果表明,Co3O4/C纳米材料与导电聚合物复合电极材料具有优异的超级电容器性能。通过恒流充放电曲线计算得到该器件具有197.83 m F/cm^2的面电容。在电化学循环10 000圈后该器件的容量仅下降9%,展示了其优异的循环稳定性;此外,该电容器具有的优异机械柔性,使其有望应用于未来柔性电子器件。

Porous Co3O4/C nano-composite is firstly synthesized by a two-step calcination method using ZIF-67 as single source precursor.Then,Co3O4/C/polyacrylamide(Co3O4/C/PAAm)composite hydrogel is fabricated by incorporating Co3O4/C composite into PAAm network through a free radical polymerization method.Polypyrrole nanoparticles with electrochemistry activity is synthesized in the as-prepared hydrogel framework by in-situ polymerization method,hence a novel kind of Co3O4/C/PAAm-PPy hydrogel electrode material is obtained.As a state-of-art demonstration,an all-solid-state flexible supercapacitor is constructed by assembling this flexible electrode material with hydrogel electrolyte.It is shown through electrochemical tests that the prepared supercapacitor exhibits excellent supercapacitor performance by delivering a specific capacitance of 197.83 m F·cm^-2that is found through galvanostatic charge-discharge curve.The capacitance of this supercapacitor declines only 9%after 10 000 electrochemistry cycles,representing a good cycling stability.Impressively,this supercapacitor shows a high mechanical flexibility under twisting and stretching deformations,which allows it to be used in powering flexible electronic appliances.