Photodissociation of water by p - and n -type polycrystalline iron oxides by using visible light (≤2.7 eV) in the absence of external potential

Abstract

A polycrystalline p/n diode assembly, consisting of pressed magnesium- and silicon-doped iron oxide powders, has been shown to photodissociate water by using visible light in the absence of any external potential. In the investigated pH range (8-14) the device produces hydrogen catalytically in amounts that are readily detectable by gas chromatography. The relatively low-power conversion efficiency of 0.05% is believed to be due to the poor change-transfer properties of the p-type iron oxide used.