Abstract

Nanocrystalline ZnO powders were synthesized by precipitation method. The npropylamine was used as capping agent. The crystallite size of ZnO powders depended on the npropylamine concentration. ZnO powders exhibited as agglomerated spherical shape. The optical band gap of ZnO powders were varied in a range of 3.204-3.219 eV. The photocatalytic efficiency of ZnO powders for degradation of methylene blue (MB) increased as a function of UV irradiation time and the photocatalytic efficiency was over 80% after UV irradiating for 1 h. The highest photocatalytic efficiency was 96% after UV irradiating for 1 h obtained from nanocrystalline ZnO powders modified with 0.025 mol of n-propylamine (R = 1). Nanocrystalline ZnO powders caused more damage to Staphylococcus aureus (S. aureus) than Escherichia coli (E. coli). © (2014) Trans Tech Publications, Switzerland.