Abstract
A tetra Ru-substituted polyoxometalate Na10[{Ru 4O4(OH)2(H2O)4}(γ- SiW10O36)2] (Ru4POM) has been successfully immobilised onto glassy carbon electrodes and indium tin oxide (ITO) coated glass slides through the employment of a conducting polypyrrole matrix and the layer-by-layer (LBL) technique. The resulting Ru4POM doped polypyrrole films showed stable redox behavior associated with the Ru centres within the Ru4POM, whereas, the POM's tungsten-oxo redox centres were not accessible. The films showed pH dependent redox behavior within the pH range 2-5 whilst exhibiting excellent stability towards redox cycling. The layer-by-layer assembly was constructed onto poly(diallyldimethylammonium chloride) (PDDA) modified carbon electrodes by alternate depositions of Ru 4POM and a Ru(II) metallodendrimer. The resulting Ru4POM assemblies showed stable redox behavior for the redox processes associated with Ru4POM in the pH range 2-5. The charge transfer resistance of the LBL films was calculated through AC-Impedance. Surface characterization of both the polymer and LBL Ru4POM films was carried out using atomic force microscopy (AFM), X-ray photoelectron spectroscopy (XPS), and scanning electron microscopy (SEM). Initial investigations into the ability of the Ru 4POM LBL films to electrocatalytically oxidise water at pH 7 have also been conducted.
Original language | English |
---|---|
Pages (from-to) | 8022-8031 |
Number of pages | 10 |
Journal | ACS Applied Materials and Interfaces |
Volume | 6 |
Issue number | 11 |
DOIs | |
Publication status | Published - 11 Jun 2014 |
Keywords
- conducting polymer
- electrocatalysis
- immobilization
- multilayer assembly
- polyoxometalates
- water oxidation