ChemElectroChem
                          Supporting Information


Less is More: A Comprehensive Study on the Effects of the
Number of Gas Diffusion Layers on Air–Cathode Microbial
Fuel Cells
Pilar Sánchez-Peña, Jesús Rodriguez, Raquel Montes, Juan Antonio Baeza,* David Gabriel,
Mireia Baeza, and Albert Guisasola
Author Contributions

P.S.-P. Conceptualization:Equal; Data curation:Lead; Investigation:Lead; Methodology:Equal; Writing – original
draft:Lead; Writing – review & editing:Equal
J.R. Data curation:Supporting; Formal analysis:Supporting; Investigation:Supporting; Methodology:Supporting; Vali-
dation:Supporting; Writing – review & editing:Supporting
R.M. Data curation:Supporting; Formal analysis:Supporting; Investigation:Supporting; Methodology:Supporting;
Writing – review & editing:Supporting
J.B. Conceptualization:Equal; Data curation:Supporting; Formal analysis:Supporting; Funding acquisition:Lead; Inves-
tigation:Equal; Methodology:Equal; Project administration:Lead; Resources:Equal; Software:Equal; Supervision:Eq-
ual; Validation:Supporting; Visualization:Supporting; Writing – original draft:Supporting; Writing – review & editin-
g:Equal
D.G. Conceptualization:Supporting; Data curation:Supporting; Formal analysis:Supporting; Investigation:Supporting;
Methodology:Supporting; Resources:Supporting; Supervision:Equal; Validation:Supporting; Writing – original draft:-
Supporting; Writing – review & editing:Supporting
M.B. Conceptualization:Equal; Data curation:Supporting; Formal analysis:Supporting; Investigation:Equal; Methodo-
logy:Supporting; Supervision:Equal; Writing – review & editing:Supporting
A.G. Conceptualization:Equal; Data curation:Equal; Formal analysis:Equal; Investigation:Equal; Methodology:Equal;
Resources:Supporting; Supervision:Equal; Validation:Supporting; Visualization:Supporting; Writing – original draft:-
Supporting; Writing – review & editing:Equal
Figure S1. SEM images: a) cathode with GDL-1 and b) cathode with GDL-4.




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Figure S2. SEM images. Cathode thickness with different number of GDL.




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Figure S3. SEM Mapping of a cross-section cathode with a different number of GDL

coating. The first column shows the cross-section, the second column shows the fluorine

distribution and the third column shows the Pt distribution.




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