Photocatalytic activity of Ca3Ti2O7 layered-perovskite doped with Rh under visible light irradiation

The photocatalytic activities of layered-perovskite Ca3Ti2O7 doped with Rh were investigated with visible light irradiation. Although the Rh-doped Ca3Ti2O7 as prepared showed low activity after an induction period, the photocatalytic activity was highly enhanced by treating the samples in reducing atmosphere without the need for an induction period. The rate of H2 evolution from an aqueous methanol solution by 3 mol% Rh-doped Ca3Ti2O7 after the reduction treatment was about 5 times higher than that before the reduction. The layered photocatalytic compounds, Ca3Ti2 − xRhxO7, showed higher stability in air than CaTi1 − xRhxO3, which consists of a simple perovskite structure.