Photoelectrochemical water splitting performance of vertically aligned hematite nanoflakes deposited on FTO by a hydrothermal method

In this report, vertically aligned hematite nanoflakes were deposited on fluorine-doped tin oxide (FTO) substrate by facile one step hydrothermal method for efficient photoelectrochemical water splitting. Further, the annealing effect on the PEC performance of α-Fe2O3 nanoflakes was studied. The α-Fe2O3 nanoflakes annealed at 300 °C yielded a high charge carrier density, lower flat band potential and enhanced photocurrent density of 2 mA/cm2 at 2.2 V vs RHE, which is higher than that of as-deposited and annealed at 600 °C hematite nanoflakes. The enhancement in photocurrent density is mainly attributed to the improved crystalline quality, high surface roughness and existence oxygen vacancy upon annealing process.