A photoanode based on ZnO nanorod array film has been successfully synthesised on zinc foil by a simple approach in the NaOH aqueous solution, without the assistance of any catalyst, templates or high temperature and its implementation as photoanode in photoelectrochemical cells for hydrogen generation from water splitting was studied. In this approach, zinc foil was used not only as a substrate but also as a zinc ion source for the direct growth of ZnO nanorod arrays. ZnO nanorod array films were characterised by scanning electron microscopy (SEM) and energy dispersive X-ray spectroscopy (EDX). The resulting ZnO nanorod showed a diameter of about 70–90 nm and the average length is estimated to be in the range of 0·5–2·0 μm. The good photoresponse of this ZnO nanorod array films have wide applications in the photoelectrochemical field. Therefore, these results suggest substantial potential of ZnO nanorod films in photoelectrochemical water splitting applications.
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