Co-catalyst free SrTiO3 nano-cube for efficient photocatalytic hydrogen production

Co-catalyst free SrTiO3 was prepared by hydrothermal method and it’s calcinated by different temperatures such as 300, 500, 700, and 900 °C to improve the photocatalytic hydrogen production. The SrTiO3 exhibits a cubic crystal structure which was revealed through X-ray diffraction (XRD) analysis. Scanning electron microscopy (SEM) images show the combination of nano spherical-needle morphology changed into nano-cubic morphology when the temperature varied from 300 to 900 °C. Further, transmission electron microscopy (TEM) result also confirms the nano-cubic crystal structure with well-resolved edges. The elemental mapping analysis shows the Sr, Ti, O elements were distributed uniformly in the prepared SrTiO3. The X-ray photoelectron spectroscopy (XPS) confirms the presence of chemical compositions and valance state of Sr, Ti, O elements in SrTiO3. The self-trapped excitons recombination of SrTiO3 was analyzed by photoluminescence (PL) analysis. The Electrochemical Impedance Spectroscopy (EIS) analysis of SrTiO3-900 °C shows the lowest electron transfer resistance which promotes effective charge separation. Among the different catalysts, SrTiO3-900 °C gives 6.8 mmol g−1 h−1 of hydrogen under Ultra-Violet irradiation.