Nanocomposites and Nanomaterials

ZnO nanopowders: synthesis approaches and properties 
Ivanov O.V.1, Fesych I.V.1, Voitenko T.A.1, Nedilko S.A.1, Dziazko O.G.1, Zelenko M.A.1, Chukova O.V.1, Nedilko S.G.1, Liedienov N.A.2,3, Pashchenko A.V.2,3,4,5, Levchenko G.G.2,3
1 Taras Shevchenko National University of Kyiv, Lva Tolstoho Street, 12, Kyiv, 01033, Ukraine.
E-mail: voitana@ukr.net
2 State Key Laboratory of Superhard Materials, International Center of Future Science of Jilin University, 130012 Changchun, China.
3 Donetsk Institute for Physics and Engineering named after O. O. Galkin, NASU,
03028 Kyiv, Ukraine.
4 Institute of Magnetism of NASU and MESU,
03142 Kyiv, Ukraine.
5 Donetsk National University of Economy and Trade named after Michael Tugan - Baranovsky, MESU, 50005 Kryvyi Rih, Ukraine.

ZnO nanopowders are widely used in optics, electronics, medicine, pharmaceutics, solar cells, photocatalysis, food, cosmetic and chemical industry etc, due to the unusual semiconducting properties of this metal oxide.
In this paper, we investigated the synthesis approaches and conditions, physical and chemical properties of ZnO nanopowders in natural polymer enviropment.
ZnO nanopowders were obtained by sol-gel technique with agar as a complexing agent. The zinc nitrate solution was added to the agar solution in calculated proportions. Produced ZnO nanopowders have been studied by FTIR, XRD, SEM and DTA/TG. X-ray studies show that all samples are crystallized in a hexagonal phase with a wurtzite structure, space group (P63mc) with high crystallinity. According to SEM results, size and morphology of ZnO nanopowders have been analyzed. Crystallite sizes and lattice strains were studied by using Williamson-Hall method. The estimated crystallite size in obtained samples ranged from 22 to 100 nm. The particles size and the crystals structure defects are influence to the X-Ray peak broadening.
The luminescence properties of prepared nanoparticles were investigated.