核壳结构锰掺杂ZIF67纳米复合材料的溶剂热法合成及其超电容特性研究

Solvothermal Synthesis of Mn-ZIF67 Core-Shell Structured Nanocomposites for Enhanced Supercapacitor

利用溶剂热法可控制备出了具有核壳结构的锰掺杂ZIF67纳米复合材料(Mn-ZIF67),通过扫描电子显微镜(FESEM)和透射电子显微镜(TEM)研究了其微观形貌和元素组成,利用X射线衍射(XRD)、傅里叶红外光谱(FT-IR)、X射线光电子能谱(XPS)分析了样品的物相组成以及元素价态.电化学测试结果表明Mn-ZIF67拥有优异的超电容特性和循环稳定性,在1A·g^(-1)的电流密度下的比电容可达257F·g^(-1),是ZIF67比电容的十几倍,并且在10000圈的充放电后仍保持着95.3%的比容量.卓越的电化学性能归因于二维的片状结构可以缩短离子的传输路径,并且提供了更多的活性位点,有利于电荷的快速转移.

Mn-ZIF67 nanocomposites with 2D nanosheet shell structure were prepared by hydrothermal method.Its micro-morphology and element composition were studied by scanning electron microscopy (FESEM) and transmission electron microscopy (TEM).The phase composition and element valence were analyzed by X-ray diffraction (XRD), Fourier infrared spectroscopy (FT-IR) and X-ray photoelectron spectroscopy (XPS).The results show that Mn-ZIF67 has excellent supercapacitance and cyclic stability.The specific capacitance of Mn-ZIF67 can reach 257 F·g^-1 at current density of 1 A·g^-1 , which is more than ten times the specific capacitance of ZIF67.Moreover, The specific capacity of Mn-ZIF67 remains 95.3% after 10 000 cycles of charge and discharge.The excellent electrochemical performance is attributed to the two-dimensional structure, which can shorten the ion transport path, provide more active sites and accelerate charge transferring.