Details

Autor(en) / Beteiligte

• Xu, Jianqi
• Ma, Guixin
• Wang, Ning
• Zhao, Simin
• Zhou, Jisheng

Titel

Borderline Metal Centers on Nonporous Metal‐Organic Framework Nanowire Boost Fast Li‐Ion Interfacial Transport of Composite Polymer Electrolyte

Ist Teil von

• Small (Weinheim an der Bergstrasse, Germany), 2022-10, Vol.18 (40), p.e2204163-n/a

Ort / Verlag

Weinheim: Wiley Subscription Services, Inc

Erscheinungsjahr

2022

Quelle

Wiley-Blackwell Journals

Beschreibungen/Notizen

• Metal‐organic frameworks (MOFs) fillers are emerging for composite polymer electrolytes (CPEs). Enhancing Lewis acid–base interaction (LABI) among MOFs, polymer and Li‐salt is expected to promote Li+‐transport. However, it is unclear how to customize a strong LABI interface. The large surface‐area of classical MOFs also interferes with clarifying the LABI influence on Li+‐transport. Herein, Bi3+ as metal centers to design colloidal‐dispersed nonporous MOFs (Bi/HMT‐MOFs) nanowire with a surface‐area of only 17.13 m2 g−1 to prepare polyethylene oxide (PEO)‐based CPEs (BMCPE) is chosen. The nonporous feature can exclude the surface‐area effect on Li+‐transport. More interestingly, Bi3+ is a typical borderline acid, which can interact with both hard‐basic PEO and soft‐basic Li‐salt anion. Accordingly, Bi/HMT‐MOFs are uniformly dispersed in the BMCPE to form a strong LABI interface with PEO and Li‐salt, promoting Li‐salt dissociation and providing rapid Li+‐transport channels. Despite the ultralow surface‐area of Bi/HMT‐MOFs, BMCPE exhibits significantly enhanced ion‐conductivity and Li+ transference number, which completely rival traditional MOFs‐filled CPEs. BMCPE also enables symmetric and full cells with excellent high‐rate performance and long‐term cycling stability. In contrast, when Bi3+ sites are obscured, electrochemical performances are obviously decreased. Therefore, employing borderline metal centers will be an effective strategy to construct a LABI interface for high‐performance MOFs‐filled CPEs. Colloidal‐dispersed Bi/HMT‐MOFs nanowires are designed as multifunctional fillers to prepare a PEO‐based composite solid electrolyte with a strong Lewis acid–base interaction interface. A strong interface can effectively promote the mobility of PEO chain and dissociation of Li‐salt to achieve rapid Li+ transport, so the electrolyte films in both symmetrical and full cells exhibit excellent performances.