BSc in Chemical Engineering from UTN (Argentina), MSc in Chemical Engineering and PhD and MBA from Technion – Israel Institute of Technology. In 1998 he joined Rafael Ltd., where he led 50 researchers in the area of high temperature batteries. In 2007 Prof. Dekel co-found CellEra, where as VP for R&D he led 15 researchers to develop the Anion Exchange Membrane Fuel Cell technology. In 2015 Prof. Dekel joined the Technion, where he heads the TEEM Lab (Technion Electrochemical Energy based on Membranes), leading the largest worldwide research group on AEMFCs. Prof. Dekel hold more than 50 patents and papers on battery and FC technologies. He currently holds about $4M government and company research grants from Israel, Europe and USA.
Authors: Nansi Gjineci, Sinai Aharonovich, Dario R. Dekel, Charles E. Diesendruck
Anion-exchange membrane fuel cells (AEMFCs) have attracted the attention of the scientific community during the past years, mostly because of the potential for eliminating the need for using costly platinum catalysts in the cells. However, the broad commercialization of AEMFCs is hampered by the low chemical stability of the cationic functional groups in the anion-conducting membranes required for the transportation of hydroxide ions in the cell. Improving the stability of these groups is directly connected with the ability to recognize the different mechanisms of the OH– attack. In this work, we have synthesized eight different carbazolium cationic model molecules and investigated their alkaline stability as a function of their electronic substituent properties. Given that N,N-diaryl carbazolium salts decompose through a single-electron-transfer mechanism, the change in carbazolium electron density leads to a very significant impact on their chemical stability. Substituents with very negative Hammett parameters demonstrate unparalleled stability toward dry hydroxide. This study provides guidelines for a different approach to develop stable quaternary ammonium salts for AEMFCs, making use of the unique parameters of this decomposition mechanism.