Suppose if the temperature is very high (1000 °C), then it leads to the fast escapism of the decomposed gas. It has been illustrated that the P-doping play a dual behaviour such as dopant as well as gas expanding agent and the P-doped porous carbon takes up protons to suppress the decomposition of water to a certain limit which is advantageous for the EDLC nature. Hence it has been interpreted that enhanced content of phosphorus function as electron donor for carbon, making the conduction band to migrate from the Fermi level, thereby promoting the electrolyte ions to be adsorbed.