【摘要】 以泡沫镍（NF）为基底,采用恒电位沉积法制备了MnO₂电极材料,以聚乙烯醇PVA-Na₂SO₄为凝胶聚合物电解质组装了二电极体系,并以H₂O-Na₂SO₄水系体系为对比进行了电化学性能研究.采用扫描电子显微镜（SEM）、透射电子显微镜（TEM）和X-射线衍射（XRD）对电极材料的形貌和结构进行表征,用循环伏安法（CV）、恒电流充放电（GCD）和交流阻抗（EIS）对电极材料及MnO₂//H2O-Na₂SO₄//MnO₂和MnO₂//PVA-Na₂SO₄//MnO₂体系的电化学性能进行测试.结果表明,MnO₂在NF上形成疏松多孔的二维纳米片网络结构;1 A·g^-1电流密度时单电极比电容可达435F·g^-1;在水系二电极体系中和899.99 W·kg^-1的功率密度下,能量密度可达1.50 W·h·kg^-1,当组建为固态体系时,499.98 W·kg^-1的功率密度下,能量密度可达1.92 W·h·kg^-1,在具有良好的循环稳定性的同时,固态体系相比于水系体系具有更大的工作电压.更多还原

【Abstract】 A nickel foam（NF） as a substrate,MnO₂ is prepared by potentiostatic deposition.Two electrode systems are assembled using PVA-Na₂ SO₄ as gel polymer electrolyte,and the electrochemical performance are studied by comparing H₂ O-Na₂ SO₄.The morphology and structure of depositied MnO₂ are characterized by scanning electron microscopy（SEM）,transmission electron microscopy（TEM） and Xray diffraction（XRD）.Electrochemical properties are examined by cycle voltammetry（CV）,galvanostatic charge-discharge（GCD） and electrochemical impedance spectroscopy（EIS） of MnO₂,MnO₂//H₂ ONa₂ SO₄//MnO₂ and MnO₂//PVA-Na₂ SO₄//MnO₂ systems.The results display that MnO₂ forms porous two-dimensional nanosheet network structure and specific capacitance is up to 435 F·g^-1 at the current density of 1 A·g^-1 in single electrode system.The energy density can reach 1.50 W·h·kg^-1 at a power density of 899.99 W·kg^-1 in the aqueous electrolyte and 1.92 W·h·kg^-1 at a power density of 499.98 W·kg^-1 in the solid system.Due to excellent cycle stability,the solid system has greater operating voltage than the aqueoussystem.更多还原