Shape Effects of Cu2O Polyhedral Microcrystals on Photocatalytic Activity

• Published in: Journal of physical chemistry. C 2010-03, Vol.114 (11), p.5073-5079
• Main Authors: Zhang, Ying, Deng, Bin, Zhang, Tierui, Gao, Daming, Xu, An-Wu
• Format: Article
• Language: English
• Subjects: C: Surfaces, Interfaces, Catalysis
• ISSN: 1932-7447; 1932-7455
• DOI: 10.1021/jp9110037

Perfect mixed 26-facet and 18-facet polyhedra of Cu2O microcrystals were successfully synthesized by a hydrothermal process with use of stearic acid as a structure-directing agent. Cu2O octahedra and cubes were also prepared under hydrothermal conditions. The obtained microstructures were characterized by X-ray diffraction (XRD), transmission electron microscopy (TEM), high-resolution TEM (HRTEM), and UV−vis spectrum. The adsorption and photocatalytic activity of as-prepared 26-facet and 18-facet Cu2O polyhedra for decomposition of methyl orange were investigated and compared to that of octahedra and cubes. The results show that mixed 26-facet and 18-facet polyhedra with dominant {110} facets have a higher adsorption and photocatalytic activity than Cu2O octahedra with dominant {111} surfaces and cubes with {100} surfaces. A higher surface energy and a greater density of the “Cu” dangling bonds on {110} facets of 26-facet and 18-facet polyhedra may be ascribed to its higher catalytic activity. Moreover, as compared with octahedra and cubes, mixed 26-facet and 18-facet polyhedra have more edges and corners, which could improve photocatalytic activity. This simple one-pot synthetic route could provide a good starting point for the research of morphology construction and shape-dependent catalytic properties of other materials.