Evaluating the potential of Pr2O3/C18H6Cu3O12 composites as positrodes with sustainable energy-power density for battery-supercapacitor hybrids

Hybrid supercapacitors (HSCs), incorporating the benefits of batteries and supercapacitors (SCs), have drawn significant research attention. In this regard, metal oxides and metal–organic frameworks (MOFs) have emerged as standout contenders for electrode materials because of their varying oxidation states, redox-active nature and immensely high porosity along with large active site ratios. Here, we fabricated praseodymium sesquioxide (Pr₂O₃) in combination with C₁₈H₆Cu₃O₁₂ MOF and compared their composites in different weight ratios. Through three-electrode characterizations, the composite with the same weight ratio revealed a remarkable specific capacity of 2046 C g⁻¹, showing enhanced performance because of the proper utilization of C₁₈H₆Cu₃O₁₂ porosity and the chemical activity of Pr₂O₃. This composite (Pr₂O₃/C₁₈H₆Cu₃O₁₂) was subsequently combined with activated carbon in a hybrid device, and numerous electrochemical characterizations were further performed. Based on the outcomes, the device demonstrated a maximum specific capacity of 310 C g⁻¹, along with energy and power densities of 67 W h kg⁻¹ and 6114 W kg⁻¹, respectively, and a capacity retention of 98%. After careful evaluation of the device, two different models were applied to estimate the approximate capacitive and diffusive contributions of the device. These findings highlight the potential of the study for future usage in battery-supercapacitor systems.