Electron Microscopy Study of Metal Sulfide Nanocrystals Formed in Langmuir–Blodgett Films

Abstract

The morphology and crystal structure of CdS, ZnS, CdZnS, and PbS nanocrystals formed by sulfidation and the subsequent annealing of the films of behenates of the respective metals using the Langmuir–Blodgett method have been investigated by high-resolution electron microscopy. It has been found that the crystal size is independent of the initial behenate film thickness. The average lateral nanocrystal size ranges from 2 to 4 nm at a film thickness of 2–14 monolayers. It has been shown that annealing in different atmospheres leads to an increase in the average nanocrystal size, morphology variation, and oxidation at the characteristic temperatures. It has been established by analyzing the interplanar spacings that the nanocrystals have hexagonal and/or cubic crystal lattices characteristic of each investigated material.