Rechargeable Zn-air batteries have drawn strong recent interest because theoretically they can combine rechargeability with the high specific energy (energy stored per unit mass) of fuel cell systems. Part of the high specific energy is due to the cathode active material (i.e. oxygen) being drawn from the surrounding air and not stored in any form in the cell like traditional rechargeable batteries (the other reason is the use of a highly condensed “fuel” in the form of an oxidizable zinc metal as the anode). However, the reactions in the air electrode are kinetically challenged, resulting in a significant lowering of the round-trip efficiency. Effective catalysts are needed to reduce the high overpotentials in these reactions, i.e. oxygen reduction reaction (ORR) during discharge process and oxygen evolution reaction (OER) during recharge process. While catalysts based on the platinum group metals (PGM) have a long developmental history and some success with fuel cells and water electrolyzers, their prohibitively high cost is disincentive to any large-scale deployment (which is however the target market for rechargeable Zn-air batteries). The need for non-PGM catalyst alternatives is therefore clear and present.
The thesis presents several designs of non-PGM electrocatalysts which have shown high activity for the oxygen reactions in alkaline solution. (Abstract shortened by UMI.)
|School:||National University of Singapore (Singapore)|
|Department:||Chemical and Biomolecular Engineering|
|School Location:||Republic of Singapore|
|Source:||DAI-B 77/06(E), Dissertation Abstracts International|
Copyright in each Dissertation and Thesis is retained by the author. All Rights Reserved
The supplemental file or files you are about to download were provided to ProQuest by the author as part of a
dissertation or thesis. The supplemental files are provided "AS IS" without warranty. ProQuest is not responsible for the
content, format or impact on the supplemental file(s) on our system. in some cases, the file type may be unknown or
may be a .exe file. We recommend caution as you open such files.
Copyright of the original materials contained in the supplemental file is retained by the author and your access to the
supplemental files is subject to the ProQuest Terms and Conditions of use.
Depending on the size of the file(s) you are downloading, the system may take some time to download them. Please be