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Transient absorption spectroscopy on subpicosecond to second time scales is used to investigate photogenerated charge carrier recombination in Si-doped nanostructured hematite (α-Fe₂O₃) photoanodes as a function of applied bias. For unbiased hematite, this recombination exhibits a 50% decay time of ∼6 ps, ∼10³ times faster than that of TiO₂ under comparable conditions. Anodic bias significantly retards hematite recombination dynamics, and causes the appearance of electron trapping on ps−μs time scales. These ultrafast recombination dynamics, their retardation by applied bias, and the associated electron trapping are discussed in terms of their implications for efficient water oxidation.