Hierarchically Structured Composite Materials for the Photocatalytic Splitting of Water with Visible Light

  • Dr Leon van de Water, The University of Sydney, Australia
  • Mr Vincent Lau, The University of Sydney, Australia
  • A/Prof Anthony Masters, The University of Sydney, Australia
  • Prof Thomas Maschmeyer, The University of Sydney, Australia

    • In this contribution we report the synthesis, characterization and photocatalytic performance of a range of composite materials that have been designed to utilize the visible part of the solar spectrum for the photocatalytic water splitting reaction. Nanoscopic cadmium sulfide (CdS) has been synthesized by controlled precipitation of Cd2+ and S2- precursors in the presence of ionic liquids (ILs). The resulting well-defined nanoparticles were subsequently immobilised inside the pores of SBA 15-(CH2)3SH, a mesoporous silica material modified with propyl thiol groups. The photocatalytic activity of the composite materials, thus prepared, was found to be substantially higher than that of highly crystalline (Wurtzite structure) commercial bulk CdS reference materials.

    Figure Hydrogen formation rates of Pt-CdS-(IL)-SBA-15-(CH2)3-SH catalysts, compared to a commercial CdS-bulk sample. Inset: TEM image of Pt-CdS-(TBA-Gly)-SBA-15-(CH2)3-SH, showing the presence of CdS nanoparticles inside the channels of the SBA-15 host.