Best Practices in Membrane Electrode Assembly for Water Electrolysis

As the demand for sustainable energy sources increases, water electrolysis has attracted huge attention in energy research fields due to its cleanliness and high purity of hydrogen generation. Electrolysis technology involves splitting water molecules into hydrogen and oxygen using electricity. The water electrolysis combined with renewable electricity makes it a key method for producing hydrogen sustainably. Herein, we present a comprehe1nsive review of water electrolysis systems for efficient hydrogen production. First, the representative components of the membrane electrode assembly (MEA) and investigations with respect to configurations of MEAs, which are categorized as catalyst-coated substrates (CCSs) and catalyst-coated membranes (CCMs), will be discussed. Then, we will introduce the state-of-the-art practices on water electrolyzers classified into alkaline water electrolyzers (AWEs), proton exchange membrane water electrolyzers (PEMWEs), and anion exchange membrane water electrolyzers (AEMWEs). Finally, critical outlooks to realize the full potential of water electrolyzers will be highlighted.