Üner, Osman; Aslan, Naim; Sarıoğlu, Akın; Semerci, Fatih; Koç, Mümin Mehmet

In this work, a facile method to prepare Bi2O3 decorated activated carbon (Bi2O3@AC) composites with high pseudocapacitive properties was presented. The inorganic–organic composites synthesized using commercial Bi2O3 and active carbon with different weight ratio. The composites were assessed using spectroscopic, microscopic, and diffractive techniques. Our assessments confirmed that active carbons were successfully doped with commercial Bi2O3 nanoparticles with different dopant rates. The electrochemical performance of as-prepared materials was researched by cyclic voltammetry, chronopotentiometry, and electrochemical impedance spectroscopy in 6 M KOH electrolyte. Higher specific capacitance was achieved for increased Bi2O3 nanoparticle in composites. The 20%-Bi2O3@AC had a maximum specific capacitance of 565 F/g at a current density of 1 A/g. In addition, the symmetrically assembled supercapacitor delivers a high energy density (23.0 Wh kg−1). Moreover, 67% of the initial capacitance is maintained after 1500 cycles at 200 mV/s, suggesting good cycling stability. Due to the synergistic effect of compositing a promising electrochemical performance was observed that was not obtained by bare AC or Bi2O3. As a result, the electrochemical properties of 20%-Bi2O3@AC composite is promising and it may be used as potential electrode for supercapacitor.

AtıfScopus29·WoS27

İncele

Yetim, Nurdan Kurnaz; Aslan, Naim; Sarıoğlu, Akın; Sarı, Nurşen; Koç, Mümin Mehmet

In this work, structural, electrochemical and optical properties of the flower-like Co3O4, NiO and CuO nanostructures were investigated. Co3O4, NiO and CuO nanoflowers were prepared using hydrothermal method. Fourier transform infrared spectroscopy was used in the confirmation of the chemical composition of the nanostructures. X-ray diffraction (XRD) was used in the analysis of crystal structures that peaks observed in the XRD analysis confirms good crystallinity of the nanoflowers. Scanning electron microscopy analysis was used to illustrate the flower-like structure of the nanostructures. Cyclic voltammetry (CV) was used in the assessment of the electrochemical properties. It was seen that flower-like Co3O4, NiO and CuO nanostructures have enhanced electrochemical properties. Using CV results, redox reaction processes of the Co3O4, NiO and CuO nanoflowers were determined. Diffusion constants were determined and NiO nanoflowers found to have the highest diffusion constant among those. Nyquist and Bode diagrams were evaluated. Energy band gaps of Co3O4, NiO, CuO nanoflowers were calculated which were found to be 2.10 eV, 2.25 eV and 3.71 eV, respectively.

AtıfScopus42·WoS40·OpenAlex46

İncele