کد مقاله | کد نشریه | سال انتشار | مقاله انگلیسی | نسخه تمام متن |
---|---|---|---|---|
6469720 | 1423982 | 2017 | 5 صفحه PDF | دانلود رایگان |
- Systematic kinetics study on PGM-free catalysts in neutral media.
- Mn-, Fe-, Co-, Ni- AAPyr were used as PGM-free catalysts.
- Fe-AAPyr had higher current densities and an apparent 4eâ transfer mechanism.
- Mn-, Co-, Ni- AAPyr seems to follow a 2Â ÃÂ 2eâ mechanism.
- Fe-AAPyr was cycled 10,000 times with minimal degradation.
Platinum group metal-free (PGM-free) catalysts based on M-N-C types of materials with M as Mn, Fe, Co and Ni and aminoantipyrine (AAPyr) as N-C precursors were synthesized using sacrificial support method. Catalysts kinetics of oxygen reduction reaction (ORR) was studied using rotating ring disk electrode (RRDE) in neutral pH. Results showed that performances were distributed among the catalysts as: Fe-AAPyr > Co-AAPyr > Mn-AAPyr > Ni-AAPyr. Fe-AAPyr had the highest onset potential and half-wave potential. All the materials showed similar limiting current. Fe-AAPyr had an electron transfer involving 4eâ with peroxide formed lower than 5%. Considering H2O2 produced, it seems that Co-AAPyr, Mn-AAPyr and Ni-AAPyr follow a 2 Ã 2eâ mechanism with peroxide formed during the intermediate step. Durability test was done on Fe-AAPyr for 10,000 cycles. Decrease of activity was observed only after 10,000 cycles.
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Journal: Electrochemistry Communications - Volume 75, February 2017, Pages 38-42