A uniform array of Aurivillius phase perovskite PbBi2Nb 2O9 photocatalyst in a nanorod configuration is fabricated on a conducting glass as a photoelectrode for a photo-electrochemical water oxidation. Dramatically improved photoactivity is demonstrated for the nanorod electrode compared to a PbBi2Nb2O9 particulate electrode. Directional electron transport in crystalline nanorods is faster than percolation through a random polycrystalline particle network.