Recent progress in polypyrrole and its composites with carbon, metal oxides, sulfides and other conducting polymers as an emerging electrode material for asymmetric supercapacitors

The necessity for rechargeable energy sources has been brought to light by the rising need for portable electronics with reduced size. Supercapacitors (SCs) have stood out among the alternatives as potential contenders to store energy efficiently. High power density (PD), prolonged cycle life, and a space between batteries and traditional capacitors are all provided by SCs. Due to a unique combination of features, SCs are an attractive solution for energy storage applications, which has attracted considerable study. Their capacity to resist several charge-discharge cycles and produce high power output makes them ideal energy devices for a variety of sectors. In order to fulfill the needs of contemporary electronic gadgets, SCs performance and efficiency improvement is the focus of research and development. They have a high capacitance and heightened cycle stability, polypyrrole (PPy) asymmetric supercapacitors (ASCs) as prospective solutions for energy storage, have attracted a lot of interest. The design, production, and performance of PPy-based ASCs are thoroughly reviewed in this work. The combination of PPy as the positive electrode with a complimentary substance, like activated carbon or transition metal oxides, as the negative electrode results in the asymmetrical arrangement. The asymmetric design, which boosts the SCs energy density (ED), allows for a wider voltage window. The PPy ASCs with customized morphologies and enhanced electrochemical characteristics have been created using a variety of synthesis techniques, such as electrochemical deposition, chemical polymerization and template-assisted approaches. An indepth discussion is also given relating to the impact of electrode material, electrolytes, overall performance of the SCs and device design. The paper also emphasizes current developments in PPy-based ASCs that have improved their capacity for energy storage, such as the use of nanomaterials and hybrid electrode architectures. The difficulties and potential outcomes for PPy ASCs are finally discussed, including scalability, costeffectiveness and integration into real-world uses. As an expert in engineering and science who wish to develop and enhance PPy ASCs. This assessment is a valuable resource for upcoming energy storage technologies.