We report the synthesis of self-organized nanoporous iron (III) oxide (haematite) viapotentiostatic anodization of iron foil. Dependent upon the applied potential andelectrolytic composition, the pore diameters range from 50 to 250 nm with a pore depth ofapproximately 500 nm. We examine the effect of electrolytic composition, anodization bathtemperature and applied potential on the dimensions of the as-synthesized nanoporousstructure. Crystallization and structural retention of the synthesized structure areachieved upon annealing the initial amorphous sample in a nitrogen atmosphere at400 °C.The crystallized nanoporous film, having a 2.2 eV bandgap, exhibited a net photocurrent density of0.51 mA cm−2 in0.5 M H2O2+1 M NaOH at 0.6 V versus Ag/AgCl under simulated AM 1.5 sunlight. Factors limiting thephotoresponse and strategies of improvement are discussed.