The influence of acetone and isopropanol crossover on the direct isopropanol fuel cell
Dominik Venus, Moritz Valeske, Matthew Brodt, Peter Wasserscheid, Simon Thiele
Abstract
Liquid organic hydrogen carriers (LOHC) offer a promising option to store and release hydrogen on demand within existing infrastructure. The direct isopropanol fuel cell (DIFC) uses the electrochemical acetone/isopropanol LOHC couple and combines the advantages of high fuel energy density at ambient conditions with CO 2 -free direct electricity production. Like other alcohol fuel cells, the DIFC combines two kinetically slow reactions, the isopropanol oxidation reaction (IOR) and the oxygen reduction reaction (ORR), requiring considerable overpotentials to drive the reactions. Accordingly, deconvoluting kinetic characteristics in the full cell is difficult. Therefore, this work uses the electrolytic electrochemical dehydrogenation unit (EDU), consisting of the IOR and the kinetically fast hydrogen evolution reaction in acidic media. This EDU then serves as an IOR full-cell model to get insights on the DIFC. Correspondingly, the demonstrated work is a comparison study investigating in-house fabricated catalyst-coated membrane electrode assemblies as hydrogen fuel cells, DIFC, and EDU. It investigates characteristic features of the DIFC and demonstrates how the acetone and isopropanol crossover affect the cathode of the DIFC.