Grym, J.Fernández Sánchez, PalomaPiqueras De Noriega, Francisco Javier2023-06-202023-06-202005-060957-448410.1088/0957-4484/16/6/051https://hdl.handle.net/20.500.14352/51112© 2005 IOP Publishing Ltd. This work was supported by MCYT (Project MAT2003-00455), by CAM(ProjectMAT/0630/2004) and by EU project HPMT-CT-2001-00215. JG acknowledges the Marie Curie fellowship in the framework of this project (Grant HPMT-GH-01-0021503).Sintering of ZnO pressed powder under Ar flow at temperatures between 1250 and 1300 degrees C leads to the formation of elongated microstructures and nanostructures, with different morphologies, on the sample surface. Rods and needles with cross-sectional dimensions ranging from tens of nanometres to several tens of microns and up to hundreds of microns in length are obtained. In an advanced stage of growth, nanoneedles are frequently arranged in bundles, forming the walls of tubes with different cross-sectional dimensions. In addition, microcombs and microfeathers consisting of well oriented nanoneedles are observed. Cathodoluminescence (CL) in the scanning electron microscope (SEM) has been used to characterize the structures grown. The formation of the elongated structures causes spectral changes, in particular an enhancement of the green-orange luminescence. High CL emission from the internal surface of the tubes has been observed.engjournal articlehttp://dx.doi.org/10.1088/0957-4484/16/6/051http://iopscience.iop.orgopen access538.9Optical-PropertiesZinc-OxideRoom-TemperaturePhotoluminescenceNanowiresMechanismsNanorodsPowdersFísica de materiales