TY - JOUR
T1 - Comparison of cathode catalyst binders for the hydrogen evolution reaction in microbial electrolysis cells
AU - Ivanov, Ivan
AU - Ahn, Yong Tae
AU - Poirson, Thibault
AU - Hickner, Michael A.
AU - Logan, Bruce E.
N1 - Funding Information:
This research was supported by National Renewable Energy Laboratory (NREL), project no. ZFA-5-52002-01, and Award KUS-I1-003-13 from the King Abdullah University of Science and Technology (KAUST).
Publisher Copyright:
© 2017 Hydrogen Energy Publications LLC
PY - 2017/6/15
Y1 - 2017/6/15
N2 - Nafion is commonly used as a catalyst binder in many types of electrochemical cells, but less expensive binders are needed for the cathodes in microbial electrolysis cells (MECs) which are operated in neutral pH buffers, and reverse electrodialysis stacks (RED),which use thermolytic solutions such as ammonium bicarbonate. Six different binders were examined based on differences in ion exchange properties (anionic: Nafion, BPSH20, BPSH40, S-Radel; cationic: Q-Radel; and neutral: Radel, BAEH) and hydrophobicity based on water uptake (0%, Radel; 17–56% for the other binders). BPSH40 had similar performance to Nafion based on steady-state polarization single electrode experiments in a neutral pH phosphate buffer, and slightly better performance in ammonium bicarbonate. Three different Mo-based catalysts were examined as alternatives to Pt, with MoB showing the best performance under steady-state polarization. In MECs, MoB/BPSH40 performed similarly to Pt with Nafion or Radel binders. The main distinguishing feature of the BPSH40 was that it is very hydrophilic, and thus it had a greater water content (56%) than the other binders (0–44%). These results suggest the binders for hydrogen evolution in MECs should be designed to have a high water content without sacrificing ionic or electronic conductivity in the electrode.
AB - Nafion is commonly used as a catalyst binder in many types of electrochemical cells, but less expensive binders are needed for the cathodes in microbial electrolysis cells (MECs) which are operated in neutral pH buffers, and reverse electrodialysis stacks (RED),which use thermolytic solutions such as ammonium bicarbonate. Six different binders were examined based on differences in ion exchange properties (anionic: Nafion, BPSH20, BPSH40, S-Radel; cationic: Q-Radel; and neutral: Radel, BAEH) and hydrophobicity based on water uptake (0%, Radel; 17–56% for the other binders). BPSH40 had similar performance to Nafion based on steady-state polarization single electrode experiments in a neutral pH phosphate buffer, and slightly better performance in ammonium bicarbonate. Three different Mo-based catalysts were examined as alternatives to Pt, with MoB showing the best performance under steady-state polarization. In MECs, MoB/BPSH40 performed similarly to Pt with Nafion or Radel binders. The main distinguishing feature of the BPSH40 was that it is very hydrophilic, and thus it had a greater water content (56%) than the other binders (0–44%). These results suggest the binders for hydrogen evolution in MECs should be designed to have a high water content without sacrificing ionic or electronic conductivity in the electrode.
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U2 - 10.1016/j.ijhydene.2017.05.089
DO - 10.1016/j.ijhydene.2017.05.089
M3 - Article
AN - SCOPUS:85020082942
SN - 0360-3199
VL - 42
SP - 15739
EP - 15744
JO - International Journal of Hydrogen Energy
JF - International Journal of Hydrogen Energy
IS - 24
ER -