High-capacity zinc-iodine flow batteries enabled by a polymer-polyiodide complex cathode

doi:10.1039/d1ta03905a

CORC > 金属研究所 > 中国科学院金属研究所

	High-capacity zinc-iodine flow batteries enabled by a polymer-polyiodide complex cathode
	Yang, Jing 1,2; Song, Yuxi 1; Liu, Qinghua 3; Tang, Ao 1
刊名	JOURNAL OF MATERIALS CHEMISTRY A
	2021-06-25
页码	6
ISSN号	2050-7488
DOI	10.1039/d1ta03905a
通讯作者	Tang, Ao(a.tang@imr.ac.cn)
英文摘要	Consuming one-third of iodide to stabilize the iodine for reversible I-/I-3(-) reactions is the major challenge for zinc-iodine flow batteries (ZIFBs) to realize high volumetric capacity. In this study, we report a polymer-polyiodide complex cathode to boost the iodide capacity of ZIFBs. By adding polyvinylpyrrolidone (PVP) to KI, electrochemical tests show that the formation of a polyiodide complex significantly promotes the oxidation of I- to I-3(-) by enabling an enhanced solubility of the I-2 film through interactions between PVP and I-2. Materials characterization and theoretical calculation further prove that the lone-pair electrons of oxygen from the carbonyl group of monomer NVP facilitate the formation of an I-O bond and result in the breaking of the I-I bond in I-2, creating an intermediate structure of NVP center dot 2I(-). Subsequently, the iodide in NVP center dot 2I(-) can further complex with oxidized I-2 forming soluble NVP-2I(3)(-), which facilitates the dissolution of the I-2 film and effectively frees up 1/3 iodide ions. Benefitting from the polyiodide complex, a ZIFB demonstrates a superior discharge capacity of 115 A h L-1 for up to 6 M I-, significantly unlocking the capacity of iodine. For long-term operation, the ZIFB with PVP in 6 M I- can continuously run for 600 cycles, affording a stable energy efficiency of 70%.
资助项目	Natural Science Foundation of Liaoning Province[2020-MS-012] ; Institute of Metal Research, Chinese Academy of Sciences
WOS研究方向	Chemistry ; Energy & Fuels ; Materials Science
语种	英语
出版者	ROYAL SOC CHEMISTRY
WOS记录号	WOS:000672933200001
资助机构	Natural Science Foundation of Liaoning Province ; Institute of Metal Research, Chinese Academy of Sciences
内容类型	期刊论文
源URL	[http://ir.imr.ac.cn/handle/321006/160043]
专题	金属研究所_中国科学院金属研究所
通讯作者	Tang, Ao
作者单位	1.Chinese Acad Sci, Inst Met Res, Shenyang, Peoples R China 2.Univ Sci & Technol China, Nano Sci & Technol Inst, Suzhou, Peoples R China 3.Natl Inst Clean & Low Carbon Energy, Beijing, Peoples R China
推荐引用方式 GB/T 7714	Yang, Jing,Song, Yuxi,Liu, Qinghua,et al. High-capacity zinc-iodine flow batteries enabled by a polymer-polyiodide complex cathode[J]. JOURNAL OF MATERIALS CHEMISTRY A,2021:6.
APA	Yang, Jing,Song, Yuxi,Liu, Qinghua,&Tang, Ao.(2021).High-capacity zinc-iodine flow batteries enabled by a polymer-polyiodide complex cathode.JOURNAL OF MATERIALS CHEMISTRY A,6.
MLA	Yang, Jing,et al."High-capacity zinc-iodine flow batteries enabled by a polymer-polyiodide complex cathode".JOURNAL OF MATERIALS CHEMISTRY A (2021):6.