Naslov
New insights into the mechanism of pseudocapacitance deterioration in electrodeposited MnO2 under negative potentials

Autori
Sopčić, Suzana ; Peter, Robert ; Petravić, Mladen ; Mandić, Zoran

Izvornik
Journal of power sources (0378-7753) 240 (2013); 252-257

Vrsta, podvrsta i kategorija rada
Radovi u časopisima, članak, znanstveni

Ključne riječi
MnO2 ; supercapacitors ; capacitance deterioration ; EQCM

Sažetak
The mechanism of deterioration of the capacitive response of electrodeposited MnO2 under reducing potentials has been studied by combined electrochemical and quartz crystal microbalance, XPS and SEM techniques. Cycling of the electrode towards cathodic potentials of −0.3 V vs. Ag/AgCl leads to irreversible reduction resulting in low valence manganese oxide, most probably Mn2O3. The reduction is accompanied by phase transformation with the uptake of considerable amounts of water into the layer. The capacitive behaviour of the MnO2 electrode fades with prolonged cycling with the concomitant change of charging/discharging mechanism.

Izvorni jezik
Engleski

Znanstvena područja
Kemija, Kemijsko inženjerstvo

POVEZANOST RADA