Relationship between size of cadmium sulfide nanoparticles and water pool diameter in reverse micelles

Abstract

Preparation of CdS nanoparticles in water sodium bis(2-ethylhexyl) sulfosuccinate isooctane reverse micelles with various water contents is studied. A direct correlation between the water pool diameter in the reverse micelles and the mean size of CdS nanoparticles is found. DOI: 10.1134/S1070427207090212 Recently a great interest has been attracted to prep- aration and characterization of nanomaterials (1). Reverse micelles in hydrocarbon solvents proved to be appropriate systems for nucleation and growth of nanoparticles. Water droplets (pools) in surfactant- based micelles act not only as microreactors, but also as steric inhibitors of aggregation of atoms and mole- cules. Micellar synthesis was used to prepare various nanomaterials, among them CdS (see review (2)). Cadmium sulfide is a semiconductor used as a work- ing medium in lasers and also as a material for fab- rication of photoresistors, photodiodes, and solar bat- teries. The advantages of the synthesis of nanopar- ticles in reverse micelles are, first, in mild conditions of the process (no high temperature and pressure is required) and, second, in that the size and shape of nanoparticles can be controlled by the micelle struc- ture and dynamics. Presently, in this research field, the major focus is on preparation and characterization of nanoparticles, but not on properties of the dispersions. Particularly, it remains to be understood whether the properties of the micelles and microemulsions are different in the course of synthesis of nanoparticles.