10.1021/acsenergylett.7b01302.s001
Camden DeBruler
Camden
DeBruler
Bo Hu
Bo
Hu
Jared Moss
Jared
Moss
Jian Luo
Jian
Luo
T. Leo Liu
T. Leo
Liu
A Sulfonate-Functionalized Viologen Enabling Neutral
Cation Exchange, Aqueous Organic Redox Flow Batteries toward Renewable
Energy Storage
American Chemical Society
2018
SPr
sulfonate-functionalized viologen molecule
Sulfonate-Functionalized Viologen Enabling Neutral Cation Exchange
AORFB
2 V
Aqueous Organic Redox Flow Batteries
efficiency
RFB
cycling
mA
cation charge-transfer mechanism
cation exchange membrane
energy storage
KI
redox flow batteries
performance
Renewable Energy Storage Redox flow batteries
2018-02-13 00:00:00
Journal contribution
https://acs.figshare.com/articles/journal_contribution/A_Sulfonate-Functionalized_Viologen_Enabling_Neutral_Cation_Exchange_Aqueous_Organic_Redox_Flow_Batteries_toward_Renewable_Energy_Storage/5900797
Redox flow batteries
using synthetically tunable and resource abundant
organic molecules have gained increasing attention for large-scale
energy storage. Herein we report a sulfonate-functionalized viologen
molecule, 1,1′-bis(3-sulfonatopropyl)-4,4′-bipyridinium, <b>(SPr)</b><sub><b>2</b></sub><b>V</b>, as an anolyte
in neutral aqueous organic redox flow batteries (AORFBs) functioning
through a cation charge-transfer mechanism. Demonstrated <b>(SPr)</b><sub><b>2</b></sub><b>V</b>/KI AORFBs manifested high
current performance from 40 to 100 mA/cm<sup>2</sup> with up to 71%
energy efficiency. In extended cycling studies, the <b>(SPr)</b><sub><b>2</b></sub><b>V</b>/KI redox flow battery delivered
stable cycling performance at 60 mA/cm<sup>2</sup>, up to 67% energy
efficiency, and 99.99% capacity retention per cycle. Density functional
theory modeling of the electrostatic charge surface of <b>(SPr)</b><sub><b>2</b></sub><b>V</b> and its charged state, <b>[(SPr)</b><sub><b>2</b></sub><b>V]</b><sup><b>–1</b></sup>, suggests charge repulsion and size exclusion enable their
compatibility with a cation exchange membrane. The present findings
expand the battery design of neutral viologen AORFBs and represent
an attractive RFB technology for sustainable and benign renewable
energy storage.