2013
Volume 13, Number 3, pp. 85–89
Effect of anions and medium pH on the formation of ZnS micro- and nanoparticles from thiourea solutions
D.S. Sofronov,1 N.N. Kamneva,1 A.V. Bulgakova,1 P.V. Mateychenko,2 V.N. Baumer,1 K.N. Belikov,1 V.A. Chebanov,1, 3 S.N. Lavrynenko4 and A.G. Mamalis5
1 Chemistry of Functional Materials Division, SSI “Institute for Single Crystals”, National Academy of Sciences of the Ukraine
2 Institute for Single Crystals, National Academy of Sciences of the Ukraine
3 V.N. Karazin Kharkiv National University, Ukraine
4 National Technical University “Kharkov Polytechnic Institute”, Ukraine
5 Project Centre for Nanotechnology and Advanced Engineering (NCSR) “Demokritos”, Athens, Greece
The effect of anion type of a Zn salt precursor and medium pH on the morphology and phase composition of ZnS particles obtained by precipitation from thiourea solutions was studied. Spherical ZnS particles from chloride and nitrate solutions crystallize in sphalerite modifications, regardless of pH. Formation of the wurtzite phase from sulfate solutions is observed only at pH 12. Decreasing pH and thiourea concentration results in the formation of mainly platelike objects. The smallest spherical agglomerates (100–200 nm) are formed by precipitation from chloride solutions at pH 12 and a thiourea:Zn2+ ratio of 4:1. Regardless of precipitation conditions ZnO is the main impurity phase.