TY - JOUR
AU - Jakes, Peter
AU - Cohn, Gil
AU - Ein-Eli, Yair
AU - Scheiba, Frieder
AU - Ehrenberg, Helmut
AU - Eichel, Rüdiger-A.
TI - Limitation of Discharge Capacity and Mechanisms of Air-Electrode Deactivation in Silicon-Air Batteries
JO - ChemSusChem: chemistry & sustainability, energy & materials
VL - 5
IS - 11
CY - Weinheim
PB - Wiley-VCH
M1 - FZJ-2012-00349
SP - 2278–2285
PY - 2012
AB - The electrocatalytical process at the air cathode in novel silicon–air batteries using the room-temperature ionic liquid hydrophilic 1-ethyl-3-methylimidazolium oligofluorohydrogenate [EMI⋅2.3 HF⋅F] as electrolyte and highly doped silicon wafers as anodes is investigated by electrochemical means, X-ray photoelectron spectroscopy (XPS), and electron paramagnetic resonance (EPR) spectroscopy. The results obtained by XPS and EPR provide a model to describe the limited discharge capacity by means of a mechanism of air-electrode deactivation. In that respect, upon discharge the silicon-air battery′s cathode is not only blocked by silicon oxide reduction products, but also experiences a major modification in the MnO2 catalyst nature. The proposed modification of the MnO2 catalyst by means of a MnF2 surface layer greatly impacts the Si–air performance and describes a mechanism relevant for other metal–air batteries, such as the lithium–air. Moreover, the ability for this deactivation layer to form is greatly impacted by water in the electrolyte.
LB - PUB:(DE-HGF)16
UR - <Go to ISI:>//WOS:000311056800026
DO - DOI:10.1002/cssc.201200199
UR - https://juser.fz-juelich.de/record/127349
ER -