蒲公英基三维分级多孔炭的制备及电化学性能

Preparation and Electrochemical Properties of Dandelion-based Three-dimensional Hierarchical Porous Carbon

以大连地区采集的新鲜蒲公英冠毛为碳源,通过清洗、活化、炭化过程制备了新颖的相互连通的三维分级多孔结构活性炭。采用热重分析仪、X射线衍射(XRD)仪、扫描电子显微镜(SEM)、拉曼光谱仪和电化学工作站对其物理性质、微观结构和电化学性能进行了表征,研究了活化温度和活化剂配比对炭电极电化学性能的影响。结果表明,活化温度为800℃、活化剂配比为2∶1的炭电极性能最优,5 A/g电流密度下电极的比电容为163 F/g,循环10000次电容无衰减,表现出极佳的稳定性。这可归因于其独特的三维互通的多孔网络结构,这种结构有利于电解液进入活性炭的内部空间,从而最大程度地增大了材料与电解液的接触面积,增大了双电层储存电荷密度,进而提升了活性炭的电化学性能。

A novel three-dimensional hierarchical porous carbon material was in the process of cleaning,activating and carbonizating of fresh dandelion pappus collected in Dalian area.Their physical properties,microstructures and electrochemcial properties were characterized by thermogravimetric analyzer,X-ray diffraction(XRD)analyzer,scanning electron microscope(SEM),Raman spectrometer and electrochemical workstation.The effects of activation temperature and ratio of activator on the electrochemical properties of carbon materials were studied.As the result,the activated carbon electrode had the best performance at 800℃and 2∶1 ratio of activator,the specific capacitance of the electrode was 163 F/g at a current density of 5 A/g with no capacitance loss after 10000 cycles,showing excellent stability.This could be attributed to its unique three-dimensional interoperable porous network architecture,which was conducive to the electrolyte into the internal space of activated carbon,thereby maximizing the contact area between the material and the electrolyte,which increased the charge density of double-layer storage and improved the electrochemical performance of activated carbon.