Overpotential

Electrolyte

Physical chemistry

Inorganic chemistry

Ion exchange

Engineering

Chemical engineering

Polymer

Alkaline fuel cell

Biochemistry

Ionomer

Nanotechnology

Electrode

Organic chemistry

Membrane

Copolymer

Chemistry

Materials science

Fuel cells

Electrochemistry

Proton exchange membrane fuel cell

Electrocatalyst

Chemical Reviews

Alkaline anion-exchange membrane (AAEM) fuel cells have attracted significant interest in the past decade, thanks to the recent developments in hydroxide-anion conductive membranes. In this article, we compare the performance of current state of the art AAEM fuel cells to proton-exchange membrane (PEM) fuel cells and elucidate the sources of various overpotentials. While the continued development of highly conductive and thermally stable anion-exchange membranes is unambiguously a principal requirement, we attempt to put the focus on the challenges in electrocatalysis and interfacial charge transfer at an alkaline electrode/electrolyte interface. Specifically, a critical analysis presented here details the (i) fundamental causes for higher overpotential in hydrogen oxidation reaction, (ii) mechanistic aspects of oxygen reduction reaction, (iii) carbonate anion poisoning, (iv) unique challenges arising from the specific adsorption of alkaline ionomer cation-exchange head groups on electrocatalysts surfaces, an...

Alkaline Anion-Exchange Membrane Fuel Cells: Challenges in Electrocatalysis and Interfacial Charge Transfer