Supercapacitive performance of hierarchical porous carbon microspheres prepared by simple one-pot method

The hierarchical porous carbon microspheres HPCMSs using furfuryl alcohol as carbon resource have been prepared by a simple one-pot method. The HPCMSs are characterized by scanning electron microscopy (SEM), transmission electron microscopy (TEM) and nitrogen adsorption/desorption isotherm at 77 K, cyclic voltammetry (CV), galvanostatic charge/discharge tests, electrochemical impedance spectroscopy (EIS) and cycle life measurements in 6 M KOH. The results show that all the HPCMSs samples, which can be fabricated by adjusting the ratio of furfuryl alcohol/tetraethyl orthosilicate, possess three-dimensionally tailored pore structures with unique micro-, meso- and macroporous systems. Particularly, the HPCMS-2 prepared at the mole ratio of 2/1 (furfuryl alcohol/tetraethyl orthosilicate) shows the largest specific surface area of 709 m² g^-1, and the HPCMS-2 electrode owns specific capacitance as high as 221 F g^-1 at the current density of 1 A g ^-1. The supercapacitor using HPCMS-2 as the active material shows high specific capacitance and excellent cycle stability, which exhibits a specific capacitance of 56 F g^-1 at the charge/discharge current density of 0.5 A g^-1. Furthermore, the HPCMS-2 supercapacitor delivers high energy densities of 6.1 Wh kg^-1 at the power density of 5000 W kg^-1, revealing a promising application in supercapacitors.