Abstract:The carbon precursor was prepared by infiltrating the furfuryl alcohol into pores of metal-organic framework (MOF-5, Zn₄O(BDC)₃, BDC=1,4 benzendicarboxylate), which was synthesized by solvothermal method. With the direct carbonization and further activation treatment with 14.5 mol/L HNO₃, a new porous carbon material was obtained. Infrared spectrum (IR), scanning electron microscope (SEM), X-ray diffraction (XRD) and N₂ adsorption/desorption isotherm were utilized to characterize the as-prepared new porous carbon material. The results show that the oxygen-enriched functional groups on the surface of the new porous carbon material obviously increase after HNO₃ activation. Due to the combination of electric double-layer capacitance of the porous carbon material and pseudo-capacitance of the oxygen-enriched functional groups, the as-prepared new porous material shows an excellent electrochemical performance. The results based on cyclic voltammetry test demonstrate that the specific capacitance is as high as 243.3 F/g at a scanning rate of 5 mV/s in 6.0 mol/L KOH electrolyte. Furthermore, the specific capacitance of the supercapacitor using this new porous carbon as the electrode active material still keeps at 74 F/g after 5 000 cycles.

Key words: porous carbon materials; Zn₄O(OOCC₆H₄COO)₃ (MOF-5); furfuryl alcohol; supercapacitor