Kiymaz, DKiymaz, ATekoglu, SMayr, FDincalp, HZafer, C2024-07-182024-07-180040-60901879-2731http://akademikarsiv.cbu.edu.tr:4000/handle/123456789/8110In 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.EnglishIMPEDANCEMNO2ELECTROLYTESSTATESPECTROSCOPYPERFORMANCENANOSHEETSREDOXArticle