A Review on Graphitic Carbon Nitride and Conducting Polymer Nanocomposite Electrodes for Supercapacitors^†

The growing demands of next-generation electric and hybrid electric vehicles and high-power electronic devices necessitate higher power density, longer cycle life, and enhanced safety at a reduced cost. To address these challenges, supercapacitors have emerged as a potential technology offering several advantages such as higher power density, excellent cycle stability, environmental friendliness, and wide temperature-range performance. Recently, research has focused on developing nanomaterials that would improve the capacitive performance of supercapacitors. Graphitic carbon nitride (g-CN or g-C₃N₄) exhibits distinct chemical and physical characteristics that are advantageous for diverse applications including energy conversion and storage. g-CN integrates the benefits of nitrogen doping, such as increased surface polarity and better surface wettability, with the advantages of carbon compounds, such as ease of availability, abundance in nature, and cost efficiency. The considerable advance in research on g-CN has inspired the development of various g-CN nanocomposites to achieve high efficiency by eliminating certain limitations. To overcome the issues related to conductivity and specific surface area, g-CN can be composited with conducting polymers (CP) as one of the modification strategies. Recently researchers have experimented with various g-CN-conducting polymer nanocomposites as electrode materials for supercapacitors. Based on the studies conducted, g-CN-conducting polymer nanocomposites have achieved good stability, adequate conductivity, and better specific capacitance. This review provides an overview of g-CN/conducting polymer nanocomposites as supercapacitor electrode materials. It covers synthetic strategies, discusses factors affecting their electrochemical performance, and outlines future research directions for high-performance supercapacitors.