ZnO nanocones: Solvothermal synthesis and photoluminescence properties

Ellipsoidal and prism shaped ZnO nanocrystals with hexagonal cross-sections have been synthesized by a simple solvothermal process. The ellipsoidal ZnO nanocrystals possessed a unique hexagonal cross-section having two sharp pointed ends and a flattened central part. The well faceted prism like particles resembled hexagonal cones in their shape. Dimensions of the nanocrystals increased systematically with the increase in the synthesis temperature. The synthesized nanocrystals exhibited near band edge UV emission centered at ∼400 nm. An additional defect related green emission band at ∼500 nm was observed from the samples synthesized at higher temperatures.