Synthesis and Electrochemical Characterizations of Nanostructured Cupric Oxide (CuO) Prepared Via a Simple One-Step Thermal Decomposition Method
Abstract
In this work, nanocrystalline cupric oxide (CuO) was successfully prepared via a simple one-step thermal decomposition method. In the synthesis process, cupric nitrate trihydrate Cu(NO3)2.3H2O was heated in a box oven at 700 oC for 1.5 hour under ambient conditions. X-ray diffraction (XRD) pattern of the prepared material approves the formation of highly pure monoclinic CuO which is supported by energy-dispersive X-ray spectroscopy (EDX) and Fourier transform infrared spectroscopy (FTIR) analysis. Scanning electron microscopy (SEM) and UV-Visible analysis confirms the formation of the nanoparticles of CuO material. The cauliflower-like morphology enhances the interactions between the electrode and electrolyte ions which is confirmed by the hydrophilic nature of the electrode surface. The direct band gap evaluated from the Tauc plot was found to be 3.23 eV. Prepared nanocrystalline CuO material shows good pseudocapacitive properties. The highest assessed value of specific capacitance (SC) was 50.0 Fg-1 at 5 mVs-1 scan rate in 1 M aqueous KOH electrolyte and that from the galvanostatic charge-discharge (GCD) analysis was 47.08 Fg-1 at current density 3 mAcm-2. Electrochemical impedance spectroscopy (EIS) shows low charge transfer resistance which helps for faster electron transport during charging and discharging.