Preparation and Stored Energy Performance of Spherical Carbon Aerogels with Uniform Size

Abstract

Different pH values of sodium carbonate solution were used as catalyst for condensation of resorcinol and formaldehyde to obtain organic gels. After high temperature carbonization, the organic gels were transformed to carbon aerogels. The obtained materials were characterized by SEM, TEM and N2 adsorption desorption test. In addition, the electrochemical performance, such as cyclic voltammetry and galvanostatic charging and discharging tests, was also conducted. SEM results show that the morphologies of carbon aerogels exhibit the transformation from sole macrosomia to sphere and eventually to sole macrosomia via elevating the pH value of precursor solution. It can be noted that different forms of carbon aerogels can be obtained via regulating the pH of the precursor solution. Especially, when the pH of sodium carbonate solution is 10.49, the prepared carbon aerogels exhibit spherical structure with uniform particle size. N2 adsorption and desorption tests show that the specific surface area of the spherical carbon can up to 526.1 m 2 /g. Cyclic voltammetry and galvanostatic charging and discharging tests show that the uniformly spherical carbon aerogels expressed more superior electrochemical performance than that of resulted monolithic based carbon aerogels. The specific capacitance of the spherical carbon aerogels can reach 85.39 F/g. Meanwhile, the specific capacitance of spherical carbon aerogels based supercapacitor can get 76.72 F/g.