Formation of ZnS nano- and microparticles from thiourea solutions

Effects of temperature, concentration of thiourea and reaction conditions (thermal heating and microwave irradiation) on morphological properties of ZnS particles obtained by sedimentation from 0.01, 0.1 and 1 М zinc nitrate solutions are studied. It is found that ZnS particles of two shapes are formed from thiourea solutions at a thermal heating (70–90 °С): agglomerated particles of the spherical shape with the dimensions of agglomerates 50–100 nm (particle size in agglomerates of 3–5 nm) and hexagonal columns in length up to 2 μm and diameter of 80–100 nm. At the microwave heating conditions (90 °С), irrespective of thiourea concentration formation of spherical ZnS particles with the size 0.6–1.2 μm is observed.