Selected-control solution-phase route to multiple-dendritic and cuboidal structures of PbSe

Well-crystalline PbSe multiple-dendritic hierarchical structures have been prepared through a facile hydrothermal process in an alkaline glycerol/water solution system using SeO2 as selenium source and hydrous hydrazine as reducing agent at 160 degrees C for 12 h. The obtained products were characterized by X-ray powder diffraction, field emission scanning electron microscopy and transmission electron microscopy, which showed that the obtained products were face-centered cubic PbSe multiple-dendritic superstructures with length of each dendrite ranging from 1.0 to 1.5 mu m. Additionally, cuboidal PbSe microcrystals with different concave faces can be obtained through a similar process except for using Se powders instead of SeO2 as selenium source and without hydrous hydrazine. The edge lengths of these cuboidal microcrystals range from 1.0 to 2.5 mu m observed by field emission scanning electron microscopy. The influencing factors for the formation of the two kinds of PbSe microstructures were discussed and the possible growth mechanisms were proposed from the point of crystallographic and kinetic views. The studies on the corresponding photoluminescence (PL) properties of the two kinds of PbSe structures are also carried out. (c) 2005 Elsevier Inc. All rights reserved.