Browsing by Author "Mayr, F"

Now showing 1 - 1 of 1
  • No Thumbnail Available
    Item
    Charge transport kinetics in flower like α-MnO2 nano-sheet and α-MnO2 nanowire based supercapacitors
    (ELSEVIER SCIENCE SA) Kiymaz, D; Kiymaz, A; Tekoglu, S; Mayr, F; Dincalp, H; Zafer, C
    In a supercapacitor, determining the cells' internal dynamics and limiting factors on the efficiency is essential for device designs. In this context, electrochemical impedance spectroscopy is a powerful tool in investigating device kinetics. This study explained the performance improvement in nanostructured MnO2 electrodes from a diffusion perspective. Firstly, we reported morphological features of flower-like nanosheet MnO2 and nanowire MnO2 with identical crystal structure (alpha-MnO2 phase) and capacitance-voltage properties. Then, the factors limiting the bias voltage-dependent capacitance efficiency were explained via electrochemical impedance spectroscopy by setting up a three-electrode system. Both resistance and capacitance vs. frequency plots provided important information on ion diffusion and charge transfer mechanisms.