Porous Fe₃O₄/carbon composite electrode material prepared from metal-organic framework template and effect of temperature on its capacitance

In this paper, we report a porous Fe₃O₄/carbon composite supercapacitor electrode material possessing great temperature variation-resistive long-term cycle stability. The material is prepared via a facile one-step calcination of an iron-based metal organic framework (Fe-MOF) template and composed of porous Fe₃O₄ nanoparticles and carbon as a result of a well-controlled incomplete annealing process of the MOF template. With this material as an electrode, a specific capacitance of 139Fg^-1 at a discharging current density of 0.5Ag^-1 can be achieved. More attractively, the specific capacitance is significantly increased when the working temperature is elevated from 0 to 60°C. Furthermore, even after 4000 cycles of charge-discharge at varied temperatures, 83.3% of the capacitance of the electrode material is retained, showing excellent temperature variation-resistive long-term cycle stability of the prepared composite electrode material. © 2014 Elsevier Ltd.