Ultra‐Stable Zn Anode Enabled by Fiber‐Directed Ion Migration Using Mass‐Producible Separator. (28th November 2022)

• Record Type: Journal Article
• Authors: Yao, Lu; Hou, Chenxin; Liu, Mingqiang; Chen, Haibiao; Zhao, Qinghe; Zhao, Yan; Wang, Yuetao; Liu, Lele; Yin, Zu‐Wei; Qiu, Jimin; Li, Shunning; Qin, Runzhi; Pan, Feng
• Is Part Of: Advanced functional materials. Volume 33:Number 5(2023)
• Page Start: n/a
• Page End: n/a
• Publication Date: 2022-11-28
• Subjects: aqueous zinc‐ion batteries -- separators -- zincophilicity functional groups -- Zn anodes -- Zn dendrite growths; Materials -- Periodicals; Chemical vapor deposition -- Periodicals; 620.11
• DOI: 10.1002/adfm.202209301
• Languages: English
• ISSNs: 1616-301X

Abstract

Abstract: Aqueous zinc‐ion battery (AZB) is a promising candidate for next‐generation energy storage owing to inherent safety and low cost. However, AZBs are currently plagued by Zn dendrite growth and undesirable side‐reactions, leading to poor cycling stability and premature failure. To restrain the uncontrollable Zn growth, a unique separator is developed based on polyacrylonitrile/graphene oxide (abbreviated as PG) composite nanofibers, which contain abundance of zincophilicity functional groups to regulate the migration and distribution of Zn 2+ ions in the separator. It is demonstrated that the cyano ligands on PG not only facilitate the dehydration of solvated Zn 2+ ions prior to deposition, but also form fast lanes to enable homogenous scattering of deposition spots. Benefiting from these features, the PG separator offers a high ionic conductivity of 7.69 mS cm ‐1 and a transference number of 0.74 for Zn 2+ . The Zn||Zn symmetrical cells with PG separators achieve an ultra‐stable cycle life over 13 000 h. Zn||Zn0.27 V2 O5 full batteries with PG separators retain 71.5% of the original capacity after 2800 cycles at a high current density of 2 A g ‐1 . This study offers future research directions toward the design of multifunctional separators to overcome the limits of Zn metal anode in AZBs. Abstract : A unique polyacrylonitrile/graphene oxide composite separator is fabricated using advanced needle‐less electrospinning technology, which directs the migration of Zn 2+ along the nanofibers with abundant zincophilicity functional groups. Fiber‐directed Zn 2+ migration promotes uniform planar plating/stripping of Zn and effectively suppresses dendrite growth, thereby significantly improving the stability of metallic Zn anodes in aqueous zinc‐ion batteries.