@article{Boldrin:2021:10.1016/j.apcatb.2021.120169,
author = {Boldrin, P and Malko, D and Mehmood, A and Kramm, UI and Paul, S and Weidler, N and Kucernak, A},
doi = {10.1016/j.apcatb.2021.120169},
journal = {Applied Catalysis B: Environmental},
pages = {1--12},
title = {Deactivation, reactivation and super-activation of Fe-N/C oxygen reduction electrocatalysts: gas sorption, physical and electrochemical investigation using NO and O2},
url = {http://dx.doi.org/10.1016/j.apcatb.2021.120169},
volume = {292},
year = {2021}
}

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TY  - JOUR
AB  - We show that gaseous nitric oxide (NO) and oxygen (O2) are useful molecular probes to uncover complex surface processes in Fe-N/C catalysts. We unravel the difference between using gaseous NO in a temperature programmed desorption experiment and using NO (and progenitors) in an electrochemical experiment. Gas phase O2 adsorption is almost exclusively desorbed as CO2, and continued exposure to oxygen increases the amount of chemisorbed oxygen species on the surface. The oxidation state of the carbon surface is an important activity determining factor, and under normal “electrochemical” conditions many of the active sites are blocked. Only by treatment at 600 °C in Ar can we free those sites for oxygen adsorption, however under atmospheric storage, and especially during the oxygen reduction reaction (ORR), the surface quickly becomes deactivated with chemisorbed oxygen species and water. We demonstrate that the material can be super-activated by reductive electrochemical treatment, both in an electrochemical three electrode cell and in a fuel cell. The energy gained following the treatment is significantly larger than the energetic cost.
AU  - Boldrin,P
AU  - Malko,D
AU  - Mehmood,A
AU  - Kramm,UI
AU  - Paul,S
AU  - Weidler,N
AU  - Kucernak,A
DO  - 10.1016/j.apcatb.2021.120169
EP  - 12
PY  - 2021///
SN  - 0926-3373
SP  - 1
TI  - Deactivation, reactivation and super-activation of Fe-N/C oxygen reduction electrocatalysts: gas sorption, physical and electrochemical investigation using NO and O2
T2  - Applied Catalysis B: Environmental
UR  - http://dx.doi.org/10.1016/j.apcatb.2021.120169
UR  - https://www.sciencedirect.com/science/article/pii/S0926337321002952?via%3Dihub
UR  - http://hdl.handle.net/10044/1/87903
VL  - 292
ER  - 

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