In situ synthesis of a Bi2O3/Bi2S3 composite heterojunction for the electrochemical characterization of supercapacitors†

Abstract

This study employs a two-step hydrothermal method to in situ introduce sulfur into a Bi₂O₃ matrix. The synthesized material displays a specific capacitance of 305.57 F g⁻¹ (2 A g⁻¹) and achieves a cycling stability of 94.12% (10 A g⁻¹), evidencing the enhancement of both capacitance and cycling stability attributed to the heterojunction. The existence of a built-in electric field was confirmed via theoretical calculations, highlighting the interactions between the electrode materials and ions. In addition, devices were constructed to demonstrate the practicality in real-world applications. This study proposes an effective methodology for the in situ synthesis of heterojunctions, offering fresh perspectives on the development of electrode materials for supercapacitors.