双钙钛矿La2CoNiO6无机纳米纤维的制备及超级电容器性能

以聚乙烯吡咯烷酮/硝酸镧-乙酸钴-乙酸镍(PVP/LCN)为前驱体, 采用静电纺丝法, 经预氧化、碳化, 制得双钙钛矿La₂CoNiO₆无机纳米纤维超级电容器电极材料. 利用X射线衍射(XRD)、扫描电镜(SEM)和透射电镜(TEM)对其形貌和结构进行表征. 结果表明, 纤维由菱形结构的La₂CoNiO₆纳米颗粒相互连接而成, 呈链状空间网状结构. 循环伏安(CV)、恒流充放电(CP)和循环寿命测试表明, La₂CoNiO₆纳米纤维电极材料在三电极体系中, 电流密度为0.25 A·g^-1时, 比电容值达335.0 F·g^-1; 在对称型双电极体系中, 电流密度为0.25 A·g^-1时, 比电容值可达到129.1 F·g^-1,表现出良好的电容性能.

Preparation and Supercapacitor Properties of Double-Perovskite La2CoNiO6 Inorganic Nanofibers

A La₂CoNiO₆ inorganic nanofiber supercapacitor electrode material was successfully prepared from a polyvinylpyrrolidone/lanthanum nitrate-cobalt acetate-nickel acetate (PVP/LCN) precursor by electrostatic spinning. Its surface morphology and structure were characterized by X-ray diffraction (XRD), scanning electron microscopy (SEM), and transmission electron microscopy (TEM). We found that the fibers were connected through rhombohedral La₂CoNiO₆ nanoparticles resulting in a linear spatial network structure. The electrochemical performance of the as-prepared inorganic nanofibers was characterized by cyclic voltammetry (CV), chronopotentiograms (CP), and cycle life tests. The results show that the La₂CoNiO₆ nanofiber electrode material has good capacitor performance. For the three-electrode system the electrode achieved a respectable specific capacitance of 335.0 F·g^-1 at 0.25 A·g^-1. For the symmetrical two-electrode system the electrode achieved a specific capacitance of 129.1 F·g^-1 at the same current density.