The Preparation And Electrochemical Tests Of Carbon Foam

Carbon foams are a new class of porous lightweight carbon materials with certain features such as light weight, high temperature tolerance, high strength, large external surface area with open cell structure, and adjustable thermal and electrical conductivity. The potential applications of carbon foam include such diverse areas as high-temperature thermal insulation, high thermally conductive heat sinks, electrodes for energy storage, energy absorption material, catalyst supports and filters, etc. Therefore, many practical potential uses are laid in carbon foams. However, few of references on carbon foams were reported, most of which are patents, It is obviously important for us to carry on this research, which will be much better if it can be put into industry.Phenolic resin foam was prepared by employing phenol formaldehyde resin as precursor which was obtained from the Synthesis of phenol and formaldehyde. Carbonize the phenolic resin foams by Embedded sintering method and the carbon foams were characterized, the main research work and conclusions are as follow:(1) Determine the structure of the phenolic resin by infrared spectroscopy. The phenolic resin foam were prepared by the phenolic resin precursor mixed with pentane and Tween -80. The result of the single factor experiment indicated that the optimum technology was that the volume ratio of Appropriate preparation conditions were V_{酚醛树脂}:V_{正戊烷}:V_{吐温-80}=10:2:1, reaction temperature at 50⁶0℃, agitate speed of 1200rpm.(2) Select suitable carbonization process by the TG.. The phenolic resin foams were carbonized by Embedded sintering method at 1000℃and the carbon foams were obtained.The morphology, crystalloid structure and surface area of the resultant carbon foams were characterized by scanning electron microscope(SEM), X-ray diffraction(XRD) and surface area measurement(BET).The results indicate that as-prepared carbon foams are porous amorphous carbon materials with very light bulk density, uniform foam, complete holes and microstructure were connected with each other. The surface areas of the carbon foams were ranging from 350 to 750m²/g. The carbon foams change from the amorphous structure to the structural of graphite with the carbonization temperature increasing. (3) The low cost carbon electrode was prepared by carbon foam, and then assembled to aqueous capacitors. The electrochemical properties of the capacitors were investigated systematically by constant current charge/discharge measurement, cyclic voltammetry and electrochemical impedance spectroscopy measurement. The result indicate that the sample have basic electrochemical characteristic of capacitors.