| Abstract: | The apparent redox response of Prussian blue (PB, iron(III) hexacyanoferrate(II)) within a paper matrix is similar to that found in conventional liquid electrolyte voltammetry using a PB-modified electrode; however part of the response is from PB which adsorbs onto the glassy carbon (GC) working electrode. Application of a Nafion® coating to the PB-impregnated paper matrix prevents transfer of PB to the GC surface. In contrast to the PB system, the redox response of the 1,1′-dimethyl-4,4′-bipyridilium (MV, methyl viologen) system, where both redox states examined are soluble, is confined wholly to the paper matrix. For the case of 1,1′-diheptyl-4,4′-bipyridilium (HV, heptyl viologen), the electrogenerated insoluble radical cation salt adsorbs onto the GC electrode, the KCl-impregnated paper acting simply as the electrolyte medium. PB can be electrogenerated within a paper matrix, with the possible application in monochrome electrochromic printing systems. |
