Efficient direct seawater electrolysers using selective alkaline NiFe-LDH as OER catalyst in asymmetric electrolyte feeds

Abstract

Direct seawater electrolysis faces fundamental catalytic and process engineering challenges. Here we demonstrate a promising seawater electrolyser configuration using asymmetric electrolyte feeds. We further investigated the faradaic O2 efficiency of NiFe-LDH in alkalinized Cl-containing electrolytes in comparison to commercial IrOx-based catalysts. Other than IrOx, NiFe-LDH prevents the oxidation of Cl- and appears highly selective for the oxygen evolution reaction in alkalinized seawater even at cell potentials beyond 3.0 Vcell.