Effect of the microstructure of carbon xerogels by using CTAB as template on their electrochemical performance

Low-cost resorcinol formaldehyde xerogels were prepared by using resorcinol and formaldehyde as precursors, Na₂CO₃ as catalyst, and  hexadecyltrimethy ammonium bromide as template through sol-gel process and ambient pressure drying without organic solvent replacement. The hexadecyltrimethy ammonium bromide template, which can be ablated completely when resorcinol formaldehyde xerogels were pyrolysised at 1000 °C, plays a role in generating pores. And the CO₂ activation process was used to further dredge micropores in the carbon xergels. The high specific surface area and high density of carbon xerogels can be obtained, which are important factors for carbon xerogels to reserve high specific capacitance. The effect of the microstructure of carbon xerogels on their electrochemical performance is a more important factor that should be considered in practical applications. With the highest specific surface area of 2796 m² g⁻¹, the specific capacitance of carbon xerogels is 181 F g⁻¹ at the scan rate of 10 mV/s by cyclic voltammetry, however, the carbon xerogel with the specific surface area of 1139 m² g⁻¹ has the largest specific capacitance of 211 F g⁻¹ at the same scan rate.