Partnership for Research and Education on Functional and Nanostructured Materials

1. Partnership for Research and Education on Functional and Nanostructured Materials Formation of ZnO-Based Multi-functional Nanostructures Through Low-Temperature Processing Oscar M. Suarez, University of Puerto Rico at Mayaguez, DMR 0351449 Typical sol-gel routes requires a thermal treatment at high temperatures (above 700ºC in most cases) to develop the desired structure. We have proposed an alternative route that allows the synthesis of nanocrystalline ZnO in ethylhexanoic acid at 250ºC wih no need for any thermal treatment. The use of the organic acid allowed the formation of a homogeneous solution containing desired metal species. Well-crystallized ZnO-based powders and films are produced after evaporating the solvent in air. The effect of the type of solvent on the optical and magnetic properties of the oxides is under current investigation. In a related project, Ni- and Cu-doped ZnO nanocrystals (6-8nm in diameter) were produced in ethanol at ambient temperature. Under suitable processing conditions, produced nanocrystals exhibited weak but noticeable ferromagnetism at room-temperature. When Fe was used as dopant species, the ferromagnetic behavior was even stronger. ZnO nanocrystals produced in ethanol at room-temperature conditions. The inset shows a single crystal. O Perales-Perez, A Parra-Palomino, R Singhal, P M Voyles,Y Zhu, W Jia and M S Tomar. “Evidence of ferromagnetism in Zn1−xMxO (M = Ni, Cu) nanocrystals for spintronics,” Nanotechnology 18 (2007), 315606