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Air Breathing Cathodes for Microbial Fuel Cell using Mn-, Fe-, Co- and Ni-containing Platinum Group Metal-free Catalysts

View Article: PubMed Central - PubMed

ABSTRACT

PGM-free catalysts were synthesized using sacrificial support method.

Catalysts were made with Fe, Co, Mn and Ni as metal center and AAPyr as precursor.

Fe-catalysts showed highest performance for ORR in microbial fuel cell.

Increase in solution conductivity led to a maximum power of 482 ± 5 μWcm−2

Increase in solution conductivity led to a maximum power of 482 ± 5 μWcm−2

No MeSH data available.


Cathode potentials measured before LSVs (a) and LSV in potassium phosphate buffer (0.1 M) (b).
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fig0020: Cathode potentials measured before LSVs (a) and LSV in potassium phosphate buffer (0.1 M) (b).

Mentions: Three separate linear sweep voltammetries of the air breathing cathodes containing M-AAPyr catalysts were run in K-PB (0.1 M) and 0.1 M KCl (Fig. 4). This investigation was done in order to study the electrocatalytic activity of Fe-AAPyr, Co-AAPyr, Mn-AAPyr and Ni-AAPyr catalysts in neutral media and “clean” conditions. After leaving the cathode exposed to the electrolyte for over 15 hours, it can be determined the open circuit potential of the different cathodes (Fig. 4.a). Particularly, Fe-AAPyr had the highest open circuit potential (0.307 ± 0.001 V vs Ag/AgCl) followed by Mn-AAPyr (0.252 ± 0.004 V vs Ag/AgCl), Co-AAPyr (0.233 ± 0.004 V vs Ag/AgCl), Ni-AAPyr (0.226 ± 0.002 V vs Ag/AgCl) while AC had the lowest open circuit potential that was 0.203 ± 0.004 V (vs Ag/AgCl). These results demonstrated that the utilization of PGM-free catalysts lowers the activation losses compared to AC. Unfortunately, the activation overpotential were still high in the range of 0.28-0.36 V compare to the theoretical value. Fe-AAPyr had the highest electrocatalytic activity followed by Co-AAPyr, Ni-AAPyr, and Mn-AAPyr. AC had the lowest electrocatalytic activity among the material investigated (Fig. 4.b). The current density of 1400 μAcm−2 was reached at a potential of −0.142 ± 0.004 V for Fe-AAPyr, −0.162 ± 0.011 for Co-AAPyr, at −0.196 ± 0.005 V for Ni-AAPyr, at −0.216 ± 0.009 V for Mn-AAPyr and at a potential of −0.268 ± 0.002 V for AC. From those results, it can be determined that Fe-AAPyr had the highest open circuit voltage at current and the highest potential at a measured current. Standard deviation detected was low indicating reproducibility in manufacturing the materials. These results follows the RDE trend (Fig. 3) except Ni-AAPyr and Mn-AAPyr in which the performances are versed when integrated into the cathode.


Air Breathing Cathodes for Microbial Fuel Cell using Mn-, Fe-, Co- and Ni-containing Platinum Group Metal-free Catalysts
Cathode potentials measured before LSVs (a) and LSV in potassium phosphate buffer (0.1 M) (b).
© Copyright Policy - CC BY
Related In: Results  -  Collection

License
Show All Figures
getmorefigures.php?uid=PMC5384433&req=5

fig0020: Cathode potentials measured before LSVs (a) and LSV in potassium phosphate buffer (0.1 M) (b).
Mentions: Three separate linear sweep voltammetries of the air breathing cathodes containing M-AAPyr catalysts were run in K-PB (0.1 M) and 0.1 M KCl (Fig. 4). This investigation was done in order to study the electrocatalytic activity of Fe-AAPyr, Co-AAPyr, Mn-AAPyr and Ni-AAPyr catalysts in neutral media and “clean” conditions. After leaving the cathode exposed to the electrolyte for over 15 hours, it can be determined the open circuit potential of the different cathodes (Fig. 4.a). Particularly, Fe-AAPyr had the highest open circuit potential (0.307 ± 0.001 V vs Ag/AgCl) followed by Mn-AAPyr (0.252 ± 0.004 V vs Ag/AgCl), Co-AAPyr (0.233 ± 0.004 V vs Ag/AgCl), Ni-AAPyr (0.226 ± 0.002 V vs Ag/AgCl) while AC had the lowest open circuit potential that was 0.203 ± 0.004 V (vs Ag/AgCl). These results demonstrated that the utilization of PGM-free catalysts lowers the activation losses compared to AC. Unfortunately, the activation overpotential were still high in the range of 0.28-0.36 V compare to the theoretical value. Fe-AAPyr had the highest electrocatalytic activity followed by Co-AAPyr, Ni-AAPyr, and Mn-AAPyr. AC had the lowest electrocatalytic activity among the material investigated (Fig. 4.b). The current density of 1400 μAcm−2 was reached at a potential of −0.142 ± 0.004 V for Fe-AAPyr, −0.162 ± 0.011 for Co-AAPyr, at −0.196 ± 0.005 V for Ni-AAPyr, at −0.216 ± 0.009 V for Mn-AAPyr and at a potential of −0.268 ± 0.002 V for AC. From those results, it can be determined that Fe-AAPyr had the highest open circuit voltage at current and the highest potential at a measured current. Standard deviation detected was low indicating reproducibility in manufacturing the materials. These results follows the RDE trend (Fig. 3) except Ni-AAPyr and Mn-AAPyr in which the performances are versed when integrated into the cathode.

View Article: PubMed Central - PubMed

ABSTRACT

PGM-free catalysts were synthesized using sacrificial support method.

Catalysts were made with Fe, Co, Mn and Ni as metal center and AAPyr as precursor.

Fe-catalysts showed highest performance for ORR in microbial fuel cell.

Increase in solution conductivity led to a maximum power of 482 ± 5 μWcm−2

Increase in solution conductivity led to a maximum power of 482 ± 5 μWcm−2

No MeSH data available.