am8b21273_si_001.pdf (791.42 kB)
Deliberate Modification of Fe3O4 Anode Surface Chemistry: Impact on Electrochemistry
journal contribution
posted on 2019-05-01, 00:00 authored by Lei Wang, Lisa M. Housel, David C. Bock, Alyson Abraham, Mikaela R. Dunkin, Alison H. McCarthy, Qiyuan Wu, Andrew Kiss, Juergen Thieme, Esther S. Takeuchi, Amy C. Marschilok, Kenneth J. TakeuchiFe3O4 nanoparticles (NPs) with an average
size of 8–10 nm have been successfully functionalized with
various surface-treatment agents to serve as model systems for probing
surface chemistry-dependent electrochemistry of the resulting electrodes.
The surface-treatment agents used for the functionalization of Fe3O4 anode materials were systematically varied to
include aromatic or aliphatic structures: 4-mercaptobenzoic acid,
benzoic acid (BA), 3-mercaptopropionic acid, and propionic acid (PA).
Both structural and electrochemical characterizations have been used
to systematically correlate the electrode functionality with the corresponding
surface chemistry. Surface treatment with ligands led to better Fe3O4 dispersion, especially with the aromatic ligands.
Electrochemistry was impacted where the PA- and BA-treated Fe3O4 systems without the −SH group demonstrated
a higher rate capability than their thiol-containing counterparts
and the pristine Fe3O4. Specifically, the PA
system delivered the highest capacity and cycling stability among
all samples tested. Notably, the aromatic BA system outperformed the
aliphatic PA counterpart during extended cycling under high current
density, due to the improved charge transfer and ion transport kinetics
as well as better dispersion of Fe3O4 NPs, induced
by the conjugated system. Our surface engineering of the Fe3O4 electrode presented herein, highlights the importance
of modifying the structure and chemistry of surface-treatment agents
as a plausible means of enhancing the interfacial charge transfer
within metal oxide composite electrodes without hampering the resulting
tap density of the resulting electrode.
History
Usage metrics
Categories
Keywords
Fe 3 O 4 dispersioncharge transfer4- mercaptobenzoic acidElectrochemistry Fe 3 O 4 nanoparticlessurface chemistry-dependent electrochemistrysurface-treatment agentsaliphatic PA counterpartFe 3 O 4 anode materialsFe 3 O 4SHion transport kineticsFe 3 O 4 Anode Surface ChemistryFe 3 O 4 NPsFe 3 O 4 electrodeBA-treated Fe 3 O 4 systems