Integration of Functional Groups to Enhance the Solubility and Stability of Viologen in Aqueous Organic Redox Flow Batteries.
ACS Appl Mater Interfaces
; 16(22): 28645-28654, 2024 Jun 05.
Article
in En
| MEDLINE
| ID: mdl-38787734
ABSTRACT
The chemical stability and energy density of redox couples are crucial factors in enhancing the durability and cost competitiveness of aqueous flow batteries. This study proposed integrating functional groups to viologen anolyte to increase its solubility and, consequently, energy density and stability for prolonged performance. Specifically, sulfonate and ester groups were selectively incorporated at the nitrogen sites of viologen to enhance solubility, leveraging their asymmetry and double hydrophilicity. Furthermore, an alpha-methyl group was introduced between the bipyridine and ester groups to enhance the chemical stability by preventing stacking and dimerization that can lead to irreversible degradation. The modified viologen demonstrated a remarkable solubility of 3.0 M in deionized water, corresponding to a volumetric capacity of 80.404 Ah L-1. Additionally, the designed viologen exhibits outstanding retention of 92.4% after 200 cycles with a minimal capacity fading rate of 0.055% per cycle in a 0.1 M flow cell test.
Full text:
1
Collection:
01-internacional
Database:
MEDLINE
Language:
En
Journal:
ACS Appl Mater Interfaces
/
ACS appl. mater. interfaces (Online)
/
ACS applied materials & interfaces (Online)
Journal subject:
BIOTECNOLOGIA
/
ENGENHARIA BIOMEDICA
Year:
2024
Document type:
Article
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