Formic acid oxidation supporting electrolytes

As already mentioned, also for the other oxygenated Cl compounds, i.e. formaldehyde [118, 138-147] and methanol [148-154], as well as for larger organic molecules, dynamic instabilities are reported. Many of them are compiled in Ref. [154], for formaldehyde oxidation on Rh and Pt [147] and methanol oxidation on Pt [155] the oscillations could be clearly identified as HN-NDR type oscillations. However, in view of the number of reaction steps involved in these oxidation reactions and of the possible complexity of the interaction of the supporting electrolyte with the dynamics even in the much simpler formic acid oxidation, it is not astonishing that any quantitative considerations should still be missing. There are some attempts to qualitatively explain the observed phenomena with reaction mechanisms that go beyond the simple dual-path model described above. However, at the time being, they are quite speculative. Therefore I shall not discuss them in more detail in this article. A summary of these works can be found in [156],... 

PANI-NTs synthesized by a template method on commercial carbon cloth have been used as the catalyst support for Pt particles for the electro-oxidation of methanol [501]. The Pt-incorporated PANl-NT electrode exhibited excellent catalytic activity and stabUity compared to 20 wt% Pt supported on VulcanXC 72R carbon and Pt supported on a conventional PANI electrode. The electrode fabrication used in this investigation is particularly attractive to adopt in solid polymer electrolyte-based fuel cells, which arc usually operated under methanol or hydrogen. The higher thermal stabUity of y-Mn02 nanoparticles-coated PANI-NFs on carbon electrodes and their activity in formic acid oxidation pomits the realization of Pt-free anodes for formic acid fuel cells [260]. The exceUent electrocatalytic activity of Pd/ PANI-NFs film has recently been confirmed in the electro-oxidation reactions of formic acid in acidic media, and ethanol/methanol in alkaline medium, making it a potential candidate for direct fuel cells in both acidic and alkaline media [502]. 

The adsorption and oxidation of the Ci molecules methanol, formaldehyde, and formic acid over a carbon-supported Pt/C fuel cell catalyst under continuous electrolyte flow have been investigated in a quantitative, comparative online DBMS study. 

Hu G, Nitze F, Barzegar HR, Sharifi T, Mikolajczuk A, Tai CW, Borodzinski A, Wagberg T (2012) Palladium nanocrystals supported on helical carbon nanofibers for highly efficient electro-oxidation of formic acid, methanol and methanol in alkaline electrolytes. J Power Sources 209 236-242... 

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