Enhanced Field-Emission and Red Lasing of Ordered CdSe Nanowire Branched Arrays

Ordered CdSe nanowire branched arrays were designed and synthesized while merging two particular structural features within a single nanomaterial. This novel CdSe nanostructure combines a branched structure and ordered single-crystalline character. The stems and branches consist of wurtzite CdSe single crystals. When measuring field-emission properties, the CdSe novel nanostructure demonstrated a low turn-on field at 4.3 +/- 0.2 V mu m(-1) for the current densities of 10 mu A cm(-2), high field-enhancement factor (1160 +/- 50), and long emission stability. It indicates that the CdSe novel nanostructure could potentially be used as field emitters. The excellent field-emission performance is due to the unique morphology of CdSe, e.g., high structural order, branched structure, perfect single-crystallinity, and tapered nanotips. In addition, red lasing, in a range 700-720 nm, of the ordered CdSe nanowire branched arrays were demonstrated. The nature of the observed lasing emission accords with coherent random lasing behavior. A lower lasing threshold was achieved due to the homoepitaxial growth of CdSe nanowire branches on the CdSe microrods stems as well.