ZnO Tetrakaidecahedrons with Coexposed {001}, {101}, and {100} Facets: Shape-Selective Synthesis and Enhancing Photocatalytic Performance

The active crystal plane determines the activity of the inorganic metal oxide-based photocatalyst, especially for the degradation of organic pollutants. The ZnO tetrakaidecahedron with different crystal faces ({001}, {101}, and {100}) is efficiently synthesized with tetramethylammonium hydroxide (TMAH) as an additive. The exposed surface of the ZnO tetrakaidecahedron can be controlled by changing the reaction concentration and reaction time. The tetradecahedral ZnO (ZnO-1, ZnO-2) nanoparticles were systematically investigated by various characterizations. On the basis of the experimental results, we speculated the possible formation mechanism of ZnO tetrakaidecahedron. In addition, the photocatalytic activity of the ZnO-1 tetrakaidecahedron is better than that of ZnO-2 nanoparticles in the photodegradation methylene blue (MB) and rhodamine B (Rh B), which is ascribed to more exposed active crystal faces, large photocurrent density, and large specific surface area.