Date:

2025-04-30

Title of Paper:

Mitigating Ring-Opening to Develop Stable TEMPO Catholytes for pH-Neutral All-Organic Redox Flow Batteries

Journal:

Adv. Funct. Mater.

Summary:

Redox-active organics are highly attractive in aqueous organic redox flow batteries (AORFBs). However, the lack of capacity dense, stable organic catholytes remains a challenge to develop energy-dense, long cycle-life AORFBs. Herein, a stable organic catholyte, 4-[3-(trimethylammonium)acetylamino]-2,2,6,6-tetramethylpiperidine-1-oxyl chloride (TMAAcNHTEMPO) is developed through rational molecular engineering using connective acetamido and trimethylammonium groups. Paired with bis-(trimethylammonium) propyl viologen tetrachloride anolyte, stable AORFBs (up to 1500 cycles) with a low capacity fade rate of ca. 0.0144% h−1 are achieved. Experimental characterizations and theoretical simulations revealed that TMAAcNH-TEMPO is largely stabilized by the reduced reactivity of the nitroxyl radical moiety that mitigates a ring-opening side reaction.

Co-author:

Hao Fan, Wenda Wu, Mahalingam Ravivarma, Hongbin Li, Bo Hu, Jiafeng Lei, Yangyang Feng, Xiaohua Sun, Jiangxuan Song*, T. Leo Liu*.

Volume:

32

Page Number:

2203032

Translation or Not:

No

Date of Publication:

2022-06-09