Homogeneous-catalytic synthesis of tetrapodlike ZnO nanocrystals and their photoluminescence properties

High-quality tetrapodlike ZnO nanocrystals (T-ZnONCs) were synthesized on ZnO catalyzed Si substrate through a modified vapor transport process, in which zinc carbonates was used as a zinc source to yield supersaturated zinc vapor. The T-ZnONCs were self-assembled by a tetrahedral core and four cylindrical nanorods (arms) with the diameter of 60–80 nm. Three luminescence bands, namely UV band at 380 nm, violet band at 440 nm and green emission at 506 nm, were identified in their photoluminescence spectrum. The strengthened UV emission implied that the cylindrical (rather than needlelike) arms improved the lattice integrity of the T-ZnONCs.