The photoelectrochemical (PEC) activity of hematite for water oxidation is hindered by sluggish charge-carrier transport and high electron-hole recombination rates. To address these issues, this study fabricated a Ti-doped Fe2O3/WO3 heterojunction photoanode on a three-dimensional (3D) Ti felt substrate via a hydrothermal process yielding Ti-doped Fe2O3 followed by WO3 growth. Characterization by XRD, Raman spectroscopy, and FESEM confirmed the composite, consisting of spherical Ti─Fe2O3 particles and irregular WO3 nanorods. The Ti─Fe2O3/WO3 heterojunction demonstrated improved PEC activity, achieving a current density of 0.106 mA cm−2 at 1.23 V versus RHE, representing approximately a threefold enhancement over the pristine Ti─Fe2O3 photoanode. This enhanced performance is attributed to effective band engineering induced by WO3 modification. Photoelectron yield and x-ray photoelectron spectroscopy indicated that the formation of the heterojunction shifted the valence and conduction band positions of Fe2O3 by 0.5 and 0.6 V, respectively, to more negative potentials. Electrochemical impedance spectroscopy and Mott–Schottky analyses confirmed that the reduced charge-transfer resistance and a high donor density (ND = 5.6 × 1021 cm−3), consistent with the enhanced PEC performance. This fabrication strategy leverages a well-engineered heterojunction on a 3D substrate to enable efficient solar-driven water oxidation. © 2026 Wiley-VCH GmbH.