Preparation of high-performance supercapacitors from waste polyurethane-based hierarchical porous carbon

The specific surface area and pore structure of carbon materials significantly impact their electrochemical performance. However, carbon materials with a uniform pore structure of micropores, mesopores, and macropores exhibit better capacitance performances. In this study, waste polyurethane was used as the carbon precursor. The polyurethane-based hierarchical porous (micropores-mesopores-macropores) carbon material was prepared by MgO template co-carbonization and KOH activation. The specific surface area and pore structure of the hierarchical porous carbon were optimized by changing the amount of magnesium acetate template and the activation temperature of KOH. The structure and composition of hierarchical porous carbon materials were characterized, and their supercapacitor performance was also tested. The results show that the hierarchical porous carbon material (PUHPC-700) has a uniform pore size distribution. Moreover, PUHPC-700 exhibited excellent supercapacitor performance, and its specific capacitance can reach 310 F g (0.5 A g). This work provides a strategy to solve the complex problem of waste polyurethane by applying it to the production of supercapacitors, which play a dual role in environmental protection.