Activated Carbon Mediated Hydrothermally Synthesized CuO Thin Films for Electrochemical Supercapacitors

In this paper, we used a simple and fast hydrothermal approach to create copper oxide (CuO) nanostructured thin film electrodes for supercapacitor applications. Nanostructures and material conductivity are critical in ion transport, and short ion and electron diffusion paths give more active sites for electrochemical processes. Activated carbon enhanced the conductivity of the CuO sample (AC). The specific capacitance obtained from CV curve is 333.3 F g −1 at 20 mV s −1 while from GCD curve is 277 F g −1 at 1 mA cm −2 . The CuOAC1 electrode preserves more than 66% of capacitance when operated at a high scan rate of 100 mV s −1 . Furthermore, the sample performs well, with an energy density of 9.63 Wh kg −1 and a power density of 509.8 W kg −1 at 1 mA cm −2 current density in 1 M acq. KOH electrolyte. The CuOAC1 sample had the lowest series (∼R s = 0.9 Ω) and charge transfer resistance (∼R s = 4.0 Ω). Also, the symmetric coin cell was assembled which exhibited areal capacitance of 16.7 mF cm −2 with 2.3 μ Wh cm −2 energy density at 500 μ W cm −2 power density measured at 2 mA cm −2 current density. This paper describes a new platform for increasing the conductivity of pseudocapacitive electrode materials, resulting in a high-performance supercapacitor for future portable electronic devices.