钠盐改性的N掺杂多孔碳的制备及其电容性能

Fabrication of N-Doped Porous Carbon Modified by Sodium Salt and Investigation on Its Capacitive Properties

杂原子掺杂是改善多孔碳材料电化学性能的有效策略之一。以壳聚糖为碳源、三聚氰胺为氮源、碳酸钠为活化剂,通过两步碳化法成功制备了一种氮掺杂多孔碳材料。采用扫描电子显微镜、透射电子显微镜、N_(2)吸附/脱附、X-射线粉末衍射、拉曼光谱、光电子能谱等方法对碳材料的微观形貌、比表面积、孔道结构和元素组成进行了分析。结果显示CMNa-1(壳聚糖预碳化产物、三聚氰胺、碳酸钠质量比为1:1:1)具有比表面积高(781.3 m^(2)/g),氮含量丰富(原子数分数5.25%)等特点。此外,在电流密度为0.5 A/g时,比电容高达333.0 F/g,同时具有优异的倍率性能(0.5~10 A/g,电容保持率为65.4%)与高稳定性(8 000次循环后比电容保持率为96.9%)。综上,所制备的钠盐改性氮掺杂多孔碳材料具有优异的电容性能,为发展绿色能源提供了新思路。

Heteroatom doping is one of the effective strategies to improve the electrochemical performance of porous carbon materials.In this work,a N-doped porous carbon material was successfully prepared by a twostep carbonization method using chitosan,melamine and sodium carbonate as a carbon source,a nitrogen source,and an activator,respectively.Subsequently,the morphology,surface area,pore structure and elemental composition of the samples were characterized by scanning electron microscopy,transmission electron microscopy,N_(2) adsorption-desorption,X-ray powder diffraction,Raman spectroscopy,and photoelectron spectroscopy.Corresponding tests demonstrate that the CMNa-1 displays characteristics of high specific surface area(781.3 m^(2)/g)and rich N content(atomic fraction 5.25%).In addition,the specific capacitance of CMNa-1 is up to 333.0 F/g at a current density of 0.5 A/g.Meanwhile,it exhibits excellent rate performance(0.5-10 A/g,capacitance retention rate of 65.4%)and high stability(specific capacitance retention rate is 96.9%after 8000 cycles).In conclusion,the as-prepared N-doped porous carbon materials modified by sodium salt demonstrate excellent capacitive performance,providing a new approach for the development of green energy.