Electrochemical Seebeck coefficient of Fe2+/Fe3+ in acetone–methanol mixed solution

Abstract

The electrochemical Seebeck coefficient (α) of Fe2+/Fe3+ in acetone–methanol (MeOH) mixed solution was systematically investigated against the acetone molar ratio (n) and molar ratio of Fe3+ to Fe (n Fe3+). At n Fe3+ = 0.75, α monotonously increases with increase in n from 0.3 mV K−1 at n = 0.00 to 3.4 mV K−1 at n = 1.00. At n Fe3+ = 0.50 and 0.25, we found anomalous dip structures in the n−α plot at n ≈ 0.9 and 0.4, respectively. Based on a spectroscopic investigation, we interpreted the observed dip structures in terms of the transition state between the FeCl4-active and FeL 6-active regions.