Abstract：Hierarchical porous carbon foam, using liquid foam as soft template and water-soluble phenolic resin as carbon source and isocyanate as curing agent, was fabricated by microwave activation method. The structure and electrochemical properties of the carbon foam were characterized. The results show that the microwave activation technology can improve the rapid evolution of H2O molecules on the liquid foam film to form a large number of nanopores on the carbon foam wall to lead to the increased specific surface area,but do not change the average pore size. The specific surface area of the activated sample is 378.2m2/g and its specific capacitance at 1A/g current density is 123.7F/g, which is about 94% higher than that of the unactived sample.And the internal resistance of the sample is reduced due to the improvement of the pore structure by microwave activation.
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