Journal article
Electrochemical promotion of NO reduction by hydrogen on a platinum/polybenzimidazole catalyst
The electrochemical promotion of catalytic NO reduction by hydrogen was studied using a (NO, H-2, Ar), Pt polybenzimidazole (PBI)-H3PO4\Pt, (H-2, Ar) fuel cell at 135degreesC. A mixture of NO/H-2/Ar was used as the working mixture at one electrode and a mixture of H-2/Ar was used as reference and counter gas at the other electrode.
Products of NO reduction (N-2 and H2O) were analyzed by an on-line mass spectrometer. At high NO+H-2+Ar flow rate (17 mL/min; 17 and 354 mL/min, respectively, at atmospheric pressure) the maximum rate enhancement ratio was 4.65. At low NO+H-2+Ar flow rate (17 mL/min; 17 and 140 mL/min, respectively), NO reduction increased 20 times even without polarization compared to the high gas flow rate.
The electrochemical promotion effect occurs at positive polarization with a maximum increase at approximately 0.08 V and with 1.5 times the zero polarization value. The promotion at the negative polarization can be attributed to the electrochemical production of the promoters. At low gas flow rates, a charge-induced change of the strength of chemisorptive bonds can take place.
Language: | English |
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Publisher: | The Electrochemical Society |
Year: | 2003 |
Pages: | D87 |
ISSN: | 19457111 and 00134651 |
Types: | Journal article |
DOI: | 10.1149/1.1566413 |
ORCIDs: | Petrushina, Irina , Bjerrum, Niels and Li, Qingfeng |