Most metal-organic frameworks(MOFs)hardly maintain their physical and chemical properties after exposure to acidic,neutral,or alkaline aqueous solutions,resulting in insufficient stability,therefore limiting their applications.Thus,the design and synthesis of stable size/morphology-controlled MOF nanocrystals is critical but challenging.In this study,dual-ligand and hard-soft-acid-base strategies were used to fabricate a variety of 3D pillared-layer[Ni(thiophene-2,5-dicarboxylate)(4,4'-bipyridine)]n MOF nanocrystals(1D nanofibers,2D nanosheets and 3D aggregates)with controllable morphology by varying the concentration of 4,4'-bipyridine and thus controlling the crystal growth direction.Owing to the shorter ion diffusion length,enhanced electron/ion transfer and strong interactions between thiophene-2,5-dicarboxylate and 4,4'-bipyridine,the 2D nanosheets showed much larger specific capacitance than ID nanofibers and 3D aggregates.A single device with an output voltage as high as 3.0 V and exceptional cycling performance(95％of retention after 5000 cycles at 3 mA cm-2)was realized by configuring two aqueous asymmetric supercapacitive devices in series.The excellent cycling property and charge-discharge mechanism are consistent with the hard-soft-acid-base theory.

Shasha Zheng;Yan Sun;Huaiguo Xue;Pierre Braunstein;Wei Huang;Huan Pang

School of Chemistry and Chemical Engineering,Yangzhou University,Yangzhou 225009,China;Institut de Chimie UMR 7177,Universite'de Strasbourg,CNRS,Strasbourg 67081,France;State Key Laboratory of Organic Electronics and Information Displays,and Institute of Advanced Materials(IAM),Nanjing University of Posts and Telecommunications,Nanjing 210023,China;Frontiers Science Center for Flexible Electronics(FSCFE),MIIT Key Laboratory of Flexible Electronics(KLoFE),Northwestern Polytechnical University,Xi'an 710072,China

国家科学评论（英文版）

[1]Shasha Zheng;Yan Sun;Huaiguo Xue;Pierre Braunstein;Wei Huang;Huan Pang-.Dual-ligand and hard-soft-acid-base strategies to optimize metal-organic framework nanocrystals for stable electrochemical cycling performance)[J].国家科学评论（英文版）,2022(07):81-89

configuring

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