Electrochemical utilization of PANI-supported Bi₂Se₃-Sm₂O₃ composite for advanced supercapacitor electrode material

Highly efficient energy storage devices are considered emerging alternative energy-saving technologies to avoid using fossil fuels. Herein, we employ a hydrothermal route to synthesize a polyaniline (PANI)-supported ternary Bi₂Se₃-Sm₂O₃/PANI composite and investigate its physical and electrochemical properties, along with pristine Bi₂Se₃ and Sm₂O₃ for supercapacitor applications. The composite exhibited pseudocapacitive behavior with an enhanced specific capacitance of 633 Fg⁻¹ at 1 Ag⁻¹ and delivered an energy density of 7.92 Wh Kg⁻¹ at a power density of 0.074 KW Kg⁻¹ in 1 M KOH electrolyte higher than pure materials as well as coulombic efficiency of 98 % and high charge transfer reduction with low Rs ~785 mΩ. The stability test demonstrates excellent electrochemical retention (9.25 % loss) after the 5000 CV cycles, which suggests its long-term application for supercapacitors. The combinative effects of conducting polymer PANI with metal oxide and metal selenide nanostructures are beneficial for designing and advancing composite electrodes for energy storage and next-generation supercapacitor applications.