Soft‐template assisted preparation of hierarchically porous graphitic carbon nitride layers for high‐performance supercapacitors

Strong π–π interaction between two‐dimensional graphitic carbon nitride (CN) layers may cause the stacking phenomenon, which leads to the decrease of its surface area and thus the capacitive properties. Hard templates are usually used to avoid the stacking phenomena. However, the use of them needs redundant removing process and may cause environmental pollution. As a result, in this work, P123 was used as the soft template to expand the inter‐layer distance and create more mesopores in the CN sheets. Benefit from the synergistic effect between the unique porous structure and the high nitrogen doping level, the formed graphitic CN (P2‐g‐CN) could exhibit high specific capacitances (520.5 and 176.0 F g−1 at the current density of 0.5 and 50 A g−1), stable cyclic behavior and satisfied energy density. The superior energy storage performances and the facile synthetic approach of P2‐g‐CN indicate its promising application as high‐performance electrode for supercapacitors and other energy storage devices. By using P123 as the soft template, the hierarchically porous structure and size of graphitic carbon nitride layers could be well tuned. As a result, the product with optimized structure and composition exhibits high and stable capacitive properties when assembled as electrodes in supercapacitors.