A biomimetic photoelectrochemical device from a molecular heterometallic sodium-manganese water splitting catalyst

A photoelectrochemical device for water splitting has been fabricated from a new water stable molecular [Na2Mn4] complex that acts as an in situ precursor towards NaMn2Ox nanoparticles under catalytic conditions when immobilized within a conductive PEDOT : PSS/Nafion composite film for optimal electron transport. The optimized photoanode architecture of ITO/TiO2/Ru/60% PEDOT : PSS/Na2Mn4/Nafion resulted in a water oxidation onset potential of 1.35 V (vs. RHE) and achieved a maximum current density of 1.31 mA cm(-2) (initial) and 0.80 mA cm(-2) (stabilized) at 1.8 V (vs. RHE) at pH 6.5.