Complex wurtzite ZnSe microspheres with high hierarchy and their optical properties

Complex wurtzite ZnSe microspheres with hierarchical fractal structure and showing strong quantum-size effects can be prepared easily by a mild solvothermal reaction in a diethylenetriamine (DETA)-deionized water (DIW) binary solution. The ZnSe microspheres are made up of nanosheets, each formed by the face-to-face pairing of two individual nanosheets. In addition, high-order, flowerlike hierarchical structures are formed by the attachment of flexible, uniform nanofibers to the exposed faces of each nanosheet pair. The surface morphology of the nanosheets changed as reaction time increased and the detailed phase-trans-formation and shape-evolution processes were studied. This approach could provide an effective strategy for tuning the electronic and optical properties of semiconductors, with special advantages over the traditional high-temperature approach, and could be extended to access other semiconductor materials with unusual morphologies and structures.