A STUDY ON THE DIFFUSION OF QUINHYDRONE IN POLYMER ELECTROLYTE

The diffusion coefficients (D) of quinhydrone were estimated in polyme r electrolytes by using non-steady-state chronoamperometry and steady- state current voltammetry. The D values have been estimated in polyeth ylene glycol (PEG) containing different concentrations, and cations of supporting electrolytes, and in different solvents over a range of te mperatures. The dependencies of electroactive probe diffusion coeffici ents on temperature, supporting electrolyte concentration and polymer chain length are discussed. The results show that D increases with inc reasing temperature and decreasing concentration of supporting electro lyte. The diffusion coefficient depends strongly on the length of poly mer chain and decreases sharply with increasing polymer chain length. The contribution of electron self-exchange has been explored and it se ems to be negligible here. (C) 1998 Elsevier Science S.A.