Anion-Exchange Membrane–Photoelectrochemical Water Splitting Using Porous Hematite Photoanodes
Dewangga Oky Bagus Apriandanu, Rizki Marcony Surya, Kosuke Beppu, Fumiaki Amano
Abstract
The requirement for liquid electrolytes to maintain their ionic conductivity hinders the practical implementation of photoelectrochemical (PEC) systems. Here, a membrane electrode assembly was fabricated by incorporating porous α-Fe 2 O 3 (hematite)-based photoanodes with an anion-exchange membrane (AEM). AEM–PEC water splitting was demonstrated in pure water without supporting electrolytes over porous hematite photoanodes under visible-light irradiation. This PEC system was operational even under low conductivity and near-neutral conditions (∼1 mS/m and pH ∼ 9). Action spectral analysis confirmed a visible-light response extending up to 600 nm, surpassing that of previously reported photoelectrodes with solid-electrolyte membranes.