Progress in active material synthesis  for EDLC and PEM Electrodes 

In EDLCs, increasing the surface area of the active material enhances capacitance due to their working mechanism. The flowchart above outlines the steps to achieve higher accessible surface area and capacitance. Additionally, introducing heteroatoms like N, S, P, and B into the carbon structure is an effective method to further boost capacitance. These heteroatoms can function as n/p-type dopants, improving electron mobility (conductivity) and enhancing the pseudo-capacitance properties of EDLCs. Fuel cells, on the other hand, require rare and expensive noble metals like Pt and Pd as electrocatalysts, especially for the cathode. However, heteroatom-doped carbon materials can serve as Non-Precious Metal Catalysts (NPMCs) by acting as electroactive centers for the oxygen reduction reaction (ORR) in the PEM cathode.