Morphology Control Of Cuprous Oxide And Their Photocatalytic Properties For Hydrogen Evolution Under Visible Light

In recent years, numerous studies are focused on the formation of heterogeneous structures by rational growing supported metal nanoparticles on the polyhedron metal oxides. Because metal oxides can not only serve as a support for a better dispersibility of metal nanoparticles, but also enhance the catalytic abilities by interacting with the metal nanoparticles. However, the deposition of metal nanoparticles on a particular crystal face is great significance for studying on catalytic reaction and understanding the relationship between the crystal surface and catalytic properties. Recent years, people have mastered synthesis technology and theory, we can successfully synthesize a lot of Cu₂O crystals with a special crystal plane, Therefore, Cu₂O becomes a representation of semiconductors.In this paper, we first studied the synthesis methods of Cu₂O polyhedron Cu₂O crystals with different morphologies were prepared by using glucose, H4N2.H2 O and hydroxylamine hydrochloride as the reducing agent. We analyzed the factors of morphology evolution, and obtained the optimal systhesis method by using H2NOH·HCl as a reducing agent.Secondly, in order to study the photocatalytic properties of hydrogen production for water splitting under visible light,we prepared a lot of cuboctahedra, cubes and octahedra Cu₂O crystals. Thephotocatalytic hydrogen production performances of different morphologies Cu₂O were tested under visible light. We explain some interesting phenomena and put forward a novel transfer model of photo-generated electrons and holes as well as a kinetic redox mechanism under illumination.In addition, we synthesized cuboctahedra Pt-Cu₂O composite photocatalyst by photodeposition in order to further improve the photocatalytic hydrogen production performance under visible light. The structure characterization and performance tests of Pt-Cu₂O composite photocatalysts were carried out. However, we found the selective deposition of Pt nanoparticles in the photodeposition process, we explained the reasons. Moreover, the stability of Pt-Cu₂O composite photocatalyst under visible light was also discussed.