Anodic deposition of metal-organic framework coatings for electrochemical applications

UoM administered thesis: Phd

  • Authors:
  • Stephen Worrall

Abstract

The electrochemical growth of metal-organic framework (MOF) coatings, utilising the anodic dissolution method, has been investigated as a means of preparing MOF coated electrodes for various electrochemical applications. A mechanistic understanding of the formation of the electrode coatings has been further developed. This understanding has been utilised to expand the scope of this technique; to allow for the electrochemical formation of Zn and Co zeoliticimidazolate framework (ZIF) coatings which was hitherto not believed to bepossible.Electrodes coated with Co and Zn ZIFs via this methodology were assessed for their capacitive behaviour and the Co ZIFs exhibited the highest, pure MOF areal capacitance values reported to date. This was attributed to the method of coating formation, which provides well adhered coatings of MOF particles integrated into the electrode surface providing a good electrical connection between the coating and the electrode. Incorporation of GO, via electrophoretic deposition during the coating growth, is shown to improve this capacitance still further. Thecorresponding Zn ZIFs exhibited resistances orders of magnitude higher than their Co analogues; modelling can explain this behaviour with the Co analogue of a given ZIF calculated to have a greater metal contribution to its LUMO leading to a more delocalised electronic structure.Electrodes coated with the Cu MOF HKUST-1 have enabled for the first time the use of MOFs as a template for the electrodeposition of anisotropic metal nanostructures. Such MOF encapsulated metal nanostructures are demonstrated to have applications in surface enhanced Raman spectroscopy (SERS). In addition the same MOF has been discovered to display a redox based hysteresis which allows for the rewritable storage of small amounts of electrically accessible data.

Details

Original languageEnglish
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Award date1 Aug 2017