A new Pb( iv )-based photocathode material Sr 2 PbO 4 with good light harvesting ability

Crystalline plumbate Sr 2 PbO 4 has been synthesized by a high temperature flux method and characterized by X-ray powder diffraction analysis, UV-vis spectroscopy, theoretical studies and SEM analysis. The results show that Sr 2 PbO 4 has indirect optical transitions with an energy of about 1.75 eV which can be assigned to the electron transfer from the state of O-2p to the mixed states of O-2p and Pb-6s. The photoelectrochemical properties of Sr 2 PbO 4 were studied for the first time, indicating that this material has p-type conductivity. The measured current density at an intensity of 47 μA cm −2 makes Sr 2 PbO 4 a promising photocathode material for visible-light-driven water splitting.