Preparation , Characterization and Electrochemical Properties of Mesoporous Biomass Carbon Derived from Corn Stalk

Corn stalk was used as raw material to prepare mesoporous biomass carbon using CaCl2 as activator. The mesoporous biomass carbon was characterized by means of X-ray diffraction (XRD), Raman spectroscopy, scanning electron microscopy (SEM), transmission electron microscopy (TEM) and N-2 adsorption-desorption analysis. The electrochemical properties of the mesoporous biomass carbon were analyzed and the formation mechanism of the mesoporous structure was explored. For the sample that calcined at 600 degrees C, the specific surface area was 370.6 m(2)/g, the average pore size was 9.65 nm. When it was applied as the anode material of lithium ion battery, the discharge capacity of the sample was 783 mA . h/g at 0.2C rate after 100 cycles. Even at 10C rate, the electrode demonstrated an excellent high rate capability of 347 mA . h/g after 1000 cycles. The sample showed good rate performance and excellent cycle stability due to the large specific surface area, which can improve the permeability of electrolyte and increase the reactive sites. Moreover, the porous structure increased the free movement space for lithium ions and charges, which was conducive to the improvement of electrochemical performance.