Integration of gradient-doped BiVO4 with single and double junction amorphous silicon photovoltaic elements provides sufficient voltage for driving overall water splitting. (a) Schematic illustration of the device structure created by van de Krol and co-workers, (b) current density as a function of applied potential showing the operational point defined by the current matching conditon for the single and double junction device, (c) chronoamperometric characteristation of the devices shown in (b), with stable solar-to-hydrogen efficiencies approaching 5% achieved for BiVO4 integrated with double junction amorphous silicon photovoltaic elements. Reprinted by permission from Springer Nature: Nature Communications.89 Copyright 2013 Nature Publishing Group.
