Nano Science and Technology InstituteNano Science and Technology Institute
Nano Science and Technology Institute 2005 NSTI Nanotechnology Conference & Trade Show
Nanotech 2005
Bio Nano 2005
Business & Investment
Nano Impact Workshop
Index of Authors
Index of Keywords
Keynote Presentations
Confirmed Speakers
Participating Companies
Industry Focus Sessions
Nanotech Expo
Special Symposia
Venue 2005
Press Room
Site Map
Nanotech 2005 At A Glance
Nanotech Proceedings
Nanotechnology Proceedings
Global Partner
nano tech
Supporting Organizations
Nanotech 2005 Supporting Organization
Media Sponsors
Nanotech 2005 Medias Sponsors
Event Contact
696 San Ramon Valley Blvd., Ste. 423
Danville, CA 94526
Ph: (925) 353-5004
Fx: (925) 886-8461

Room-Temperature Synthesis and Characterization of Highly Monodisperse Transition Metal-Doped ZnO Nanocrystals

S.P. Singh, O. Perales-Perez, M.S. Tomar, A. Parra-Palomino and A. Ruiz-Mendoza
University of Puerto Rico, PR

room-temperature synthesis, characterization, monodisperse, nanocrystals, doped-ZnO

We present here the results of our current efforts on size-controlled synthesis of bare and Mn- and Co-doped ZnO nanocrystals. Stable suspensions of these materials were produced in ethanol solutions at room-temperature. XRD characterization of the products verified the fast formation of ZnO nanocrystals. The actual incorporation of Mn and Co into the ZnO host was suggested by XRD analyses; however, their presence delayed the formation of the host structure. HRTEM analyses revealed the high monodispersity of the 5-8 nm nanocrystals. UV-visible and photoluminescence measurements evidenced not only the nanocrystalline nature of the samples but also the continuous growth of the nanocrystals when aged in their mother liquors. The estimated band gap energy of non-aged ZnO nanocrystals was 3.72eV and decreased down to 3.46eV after 48 hours of aging, when no further growth was observed. The UV-visible analyses also confirmed the inhibition of crystal growth when the nanocrystals were coagulated by n-heptane and redispersed in fresh ethanol. SQUID measurements indicated that as-synthesized doped ZnO nanocrystals were paramagnetic at room-temperature in contrast with the diamagnetic nature of bare ZnO. The effect of thermal treatment of nanocrystals and the dependence of magnetic properties with crystal size will also be discussed.

Back to Program

Sessions Sunday Monday Tuesday Wednesday Thursday Authors

Nanotech 2005 Conference Program Abstract

Gold Sponsors
Nanotech Gold Sponsors
Silver Sponsors
Nanotech Silver Sponsors
Gold Key Sponsors
Nanotech Gold Key Sponsors
Nanotech Ventures Sponsors
Nanotech Ventures Sponsors
Nanotech Sponsors
News Headlines
NSTI Online Community

© Nano Science and Technology Institute, all rights reserved.
Terms of use | Privacy policy | Contact