book of abstracts - IM2NP

A B S T R A C T S WEDNESDAY, JUNE 30 N A N O S E A 2 0 1 0
2 – Abstract
We report on the occurrence of enhanced photoluminescence and room temperature ferromagnetism in Codoped
ZnO nanoparticles (NPs). Doping is performed by ball milling of 3 wt% of Co mixed with ZnO
nanopowders (commercial) for durations of 2-8 hrs. X-ray diffraction data and high resolution transmission
electron microscopy (HRTEM) confirm the absence of metallic Co clusters or any other phase different from
würtzite-type ZnO. The field dependence of magnetization (M–H curve) measured at room temperature
exhibited the clear ferromagnetic characteristic with saturation magnetization (Ms) and coercive field (Hc) of
, respectively. Post-
-visible absorption
spectra show red-shift in the absorption peaks in the Co doped ZnO NPs indicating incorporation of Co
atoms in ZnO lattice. Room temperature photoluminescence studies show enhanced near-band-edge
emission at 378 nm in the doped NPs as compared to the undoped ZnO NPs indicating negligible presence of
defects in the doped ZnO crystals. This work demonstrates the feasibility of large scale production of
ferromagnetic semiconductors that are potentially useful for building nanoscale spintronic devices.
3 – Conclusion
We have achieved Co doping of ZnO nanoparticles by planetary ball milling technique. Structural analysis
confirm the absence of metallic Co clusters or any other phase different from würtzite-type ZnO. We
observed clear room temperature ferromagnetism with saturation magnetization (Ms) and coercive field (Hc)
of the order o
systematically and it is concluded that defects do not play any significant role in the FM of CoZnO. We also
observed enhanced PL emission in the Co doped ZnO NPs.
12H20-12H40
Study of Composition, Structure and Optical Properties of Nano-structured
ZnS:Mn Thin Films Prepared by Chemical Deposition Method.
Alireza Goudarzia, Reza Sahraeib ,Chang-Sik Hac,* (aDept.of Polymer Engineering, Golestan
University,Gorgan,Iran.,bDept.of Chemistry, University of Ilam, Ilam, cPolymer Science and Engineering Pusan
National University, Busan 609-735,Republic of Korea) csha@pusan.ac.kr
1 – Introduction:
Zinc sulfide is a semiconductor suitable for use as a host matrix for a wide variety of dopants on account of
its wide energy band gap. The luminescent properties of this material doped with Mn have proven to be
suitable for electroluminescence applications. Manganese is generally incorporated as Mn2+ ion in the
substitutional sites of the ZnS lattice. ZnS:Mn films, however, have been usually prepared by expensive and
difficult (strict) methods. Doping zinc sulfide with manganese is usually made by thermal diffusion of Mn
salt at high temperature, such as, for example, spray pyrolysis method1,2. In this work, we report the
preparation of Mn2+ doped ZnS thin films by chemical bath deposition (CBD) method at different
temperatures and Mn2+ concentrations. The CBD method is simple, convenient and cost effective because it
is normally carried out at atmospheric pressure (usually in air) and near ambient temperatures. It has the
advantage of not requiring vacuum systems and is compatible with large area deposition.
2 – Abstract
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