Xu Liu, Chaoyu Bao, Zengrong Wang, Chenjing Liu, Xuri Zhang, Shuran Yang, Ya-Ke Li, Gao-Lei Hou, Ni Yan, Gang He
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引用次数: 0
Abstract
The aqueous organic redox flow batteries (AORFBs) are recognized as the most promising large-scale storage technology for long-duration energy storage (LDES). Although viologen derivatives are widely used as anolyte materials for AORFBs, their practical application is strongly limited by weak conjugation and unstable radicals. Here, we present a novel thienoviologen derivative, [(NPr)2SV]Cl4, achieved utilizing a meta-substitution approach based on the pristine viologen derivatives ( [(NPr)2V]Cl4). Compared to other ortho- and para-substitution methods, this strategy features a locked plane configuration (0.14°), effectively regulating π-π interactions and suppressing reactivity between radical and oxygen, which is confirmed via X-ray single-crystal structural analyses, spectroscopy techniques, molecular dynamics simulation accompanied by linear ion trap mass spectrometry experiments. Additionally, the meta-substituted [(NPr)2SV]Cl4 significantly improves water solubility (2.39 M), enhances aromaticity, and extends radical lifetime compared with para-substituted [(NPr)2TV]Cl4. Consequently, the cycling stability of the [(NPr)2SV]Cl4-based AORFB over 2500 cycles is 4.1 times higher than that of [(NPr)2TV]Cl4. Furthermore, the 0.5 M battery delivers an impressive 99.83% capacity retention during 200 cycles and a power density of 147 mW cm-2.
期刊介绍:
Energy Storage Materials is a global interdisciplinary journal dedicated to sharing scientific and technological advancements in materials and devices for advanced energy storage and related energy conversion, such as in metal-O2 batteries. The journal features comprehensive research articles, including full papers and short communications, as well as authoritative feature articles and reviews by leading experts in the field.
Energy Storage Materials covers a wide range of topics, including the synthesis, fabrication, structure, properties, performance, and technological applications of energy storage materials. Additionally, the journal explores strategies, policies, and developments in the field of energy storage materials and devices for sustainable energy.
Published papers are selected based on their scientific and technological significance, their ability to provide valuable new knowledge, and their relevance to the international research community.