Rational engineering of Cu-BTC/Al2S3@PPy with improved charge transport and interfacial properties for energy storage and the hydrogen evolution reaction

Abstract

Currently, energy storage devices are essential to the existing energy landscape, and one promising modern energy storage solution is a supercapacitor, characterized by high cycling stability, longevity, and ever-increasing working voltage. In the current study, Cu-BTC/Al₂S₃@PPy was prepared by the hydrothermal method, and its electrochemical properties were widely studied. Characterization techniques were used to confirm the successful fabrication of this nanohybrid electrode. The crystalline structure was confirmed by X-ray diffraction (XRD) examination, and a well-developed morphology was revealed by scanning electron microscopy (SEM). Fourier transform infrared spectroscopy (FTIR) described functional groups present in the hybrid material, and Brunauer–Emmett–Teller (BET) analysis confirmed that the hybrid material has a high specific surface area (SSA). Cu-BTC/Al₂S₃@PPy was systematically investigated for its electrochemical performance in a two- and three-electrode configuration with 3.0 M KOH as an alkaline electrolyte. The results confirm that the obtained Cu-BTC/Al₂S₃@PPy//AC electrode has energy storage possibilities. Galvanostatic charge discharge (GCD) characterization shows that this hybrid electrode attains a specific capacity (Q_s) of 1450 C g⁻¹ and an energy density (E_d) of 81.8 Wh kg⁻¹ and a power density (P_d) of 1600 W kg⁻¹, far beyond those of the as-synthesized Cu-BTC and Al₂S₃. The results confirm that the Cu-BTC/Al₂S₃@PPy electrode can serve as a promising supercapacitor hybrid material with superb performance and a broad range of applications in energy storage systems with the HER.