TY - JOUR
T1 - Peptide-Modified Electrode Surfaces for Promoting Anion Exchange Ionomer Microphase Separation and Ionic Conductivity
AU - Su, Zihang
AU - Kole, Subarna
AU - Harden, Leigh C.
AU - Palakkal, Varada M.
AU - Kim, Chuloong
AU - Nair, Greshma
AU - Arges, Christopher G.
AU - Renner, Julie N.
N1 - Funding Information:
This work by C.G.A. and his laboratory was supported by the National Science Foundation (Award No. 1703307). He also acknowledges the LSU Nanofabrication Facility for preparing the IDEs, the LSU Shared Instrumentation Facility (SIF) for use of the Renishaw in Via Reflex Raman Spectroscope, and Mr. Daniel Willis for assisting us in thermal evaporation of titanium and gold for the preparation of IDEs. C.G.A. also thanks Mr. Deepra Bhattacharya for helping prepare Figure 1. The work performed by J.N.R. and her laboratory was supported by the United States Department of Agriculture (Award No. 2018-68011-28691). J.N.R. also appreciates support from an NSF-sponsored Research Experiences for Undergraduates Award (No. 1659394). We thank the Swagelok Center for Surface Analysis of Materials located at CWRU for their work in helping obtain AFM data, and the Protein Expression Purification Crystallization and Molecular Biophysics Core at CWRU for assistance with DLS measurements.
Publisher Copyright:
Copyright © 2019 American Chemical Society.
PY - 2019/10/7
Y1 - 2019/10/7
N2 - Ionomer binders are critical materials for delivering ions to and from electrocatalyst surfaces in fuel cell and water electrolyzer technologies. Most studies examine these materials as bulk polymer electrolyte membranes, and comparatively little attention has been given to their behavior on electrode surfaces as thin films. This report demonstrates that sequence-defined peptides anchored to electrode surfaces, or the solvent vapor annealing processing, alters the microstructure configuration of anion exchange ionomers (AEIs). It is observed that moderately sized microphase-separated ionic domains of the AEI, obtained either by peptide-modified electrodes or solvent vapor annealing, give rise to a two- to three-fold increase in thin-film in-plane ionic conductivity. Interestingly, the use of peptide-modified electrodes, in conjunction with solvent vapor annealing, yields excessively large ionic grains that compromise ionic conductivity. Overall, the judicious use of sequence-defined peptides adsorbed to electrode surfaces, or solvent vapor annealing, encourage the appropriate microstructures of thin-film AEIs resulting in ameliorated ionic conductivity.
AB - Ionomer binders are critical materials for delivering ions to and from electrocatalyst surfaces in fuel cell and water electrolyzer technologies. Most studies examine these materials as bulk polymer electrolyte membranes, and comparatively little attention has been given to their behavior on electrode surfaces as thin films. This report demonstrates that sequence-defined peptides anchored to electrode surfaces, or the solvent vapor annealing processing, alters the microstructure configuration of anion exchange ionomers (AEIs). It is observed that moderately sized microphase-separated ionic domains of the AEI, obtained either by peptide-modified electrodes or solvent vapor annealing, give rise to a two- to three-fold increase in thin-film in-plane ionic conductivity. Interestingly, the use of peptide-modified electrodes, in conjunction with solvent vapor annealing, yields excessively large ionic grains that compromise ionic conductivity. Overall, the judicious use of sequence-defined peptides adsorbed to electrode surfaces, or solvent vapor annealing, encourage the appropriate microstructures of thin-film AEIs resulting in ameliorated ionic conductivity.
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U2 - 10.1021/acsmaterialslett.9b00173
DO - 10.1021/acsmaterialslett.9b00173
M3 - Article
AN - SCOPUS:85089737349
SN - 2639-4979
VL - 1
SP - 467
EP - 475
JO - ACS Materials Letters
JF - ACS Materials Letters
IS - 4
ER -