• 文献标题:   Charge percolation in metal-organic framework (HKUST-1)-graphene nanocomposites
  • 文献类型:   Article
  • 作  者:   SAFY MEA, HAIKAL RR, ELSHAZLY B, HAMDY A, ALI F, MAAROUF AA, ALKORDI MH
  • 作者关键词:   mof conductivity, mofgraphene composite, charge percolation, supercapacitor
  • 出版物名称:   APPLIED MATERIALS TODAY
  • ISSN:   2352-9407
  • 通讯作者地址:   Zewail City Sci Technol
  • 被引频次:   1
  • DOI:   10.1016/j.apmt.2020.100604
  • 出版年:   2020

▎ 摘  要

Modulating the conductivity of microporous metal-organic frameworks (MOFs) through formulation of composites with graphene (G), as the conductive element, is demonstrated, without being limited to a particular MOF composition or topology. The synthesis allows for varying G content within the composite systematically, resulting in highly electrically conductive composites beyond 30 wt% G. The charge percolation model can effectively be utilized to describe the macroscopic electrical conductivity of the synthesized composites. Starting from a non-conductive MOF (HKUST-1, sigma = 2*10(-8) S m(-1)), enhanced conductivity can be accessed through increasing the G wt%, reaching more than nine orders of magnitude increase in conductivity up to 23.3 S m(-1) for the composite containing 59.4 wt% G. A charge percolation threshold of 30 wt% G was observed, where sufficient G-G contacts were established within the composite. The ab initio DFT calculations on Cu-paddlewheel@G model indicated several non-covalent interactions, including OH center dot center dot center dot pi and pi-pi interactions, governing the deposition of the MOF on top of G (range of-101.3 kJ/mol to-113.8 kJ/mol). This approach is potentially transferable to the vast majority of MOFs, as surface functionalization of the conductive filler is not a prerequisite for the attainment of bottom-up assembly of the MOF@G. (C) 2020 Elsevier Ltd. All rights reserved.