| As a liquid, air independent and reliable fuel cell with high energy density, direct borohydride/peroxide fuel cell (DBHFC) is considered as one of the best candidates for portable power systems for space and submarine application. Currently the main challenge of DBHFC is hydrogen formation from borohydride hydrolysis instead of electro-oxidation. To solve this problem, catalysts with high activity for borohydride electrochemical oxidation but low activity for borohydride hydrolysis is required.Nanoporous gold is capable to electrochemically oxidize borohydride and theoretically generate 8 electrons transfer. What's more, as non-particle catalyst, the appearance of isolate catalyst particle can be fully avoided.This paper demonstrates a new and facile approach to fabricate NPG with uniform bi-continuous structure of gold and porousity from 100nm Au/Ag alloy film. Not involving strong acid or additional electrochemical equipment, the method simply employ Fe3+ to selective dissolute Ag content from the initial Au/Ag alloy with the help of Cl- which apparently reduce the redox potential of silver. Ammonia is then used to clean up AgCl and NPG is obtained. The electrochemical property and application of the as-prepared NPG in DBHFC has been investigated. A peak power density of 175mW cm-2 was obtained without any optimization of the cell by NPG fabricated by our method, which is much higher than the peak power of 82mW cm-2 obtained in the cell using NPG by traditional method of concentrated nitric acid.
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