Fabrication and characterization of solid PbI₂ nanocrystals

Abstract

Lead iodide nanoparticles are synthesized in reverse micelle solution of AOT/H2O/n-heptane. Optical absorption spectra and TEM analysis indicated the formation of crystalline particles with an average radius of 1.5 nm, which is less than the Bohr radius of the exciton (1.9 nm) in bulk PbI2. Using theoretical models and optical spectra of quantum confined PbI2 nanoparticles, a radius of 1.5 nm and a thickness of 1.7 nm was calculated, which are in full agreement with the TEM results. Particles were isolated from the dispersed medium and were analysed by powder XRD and Raman spectroscopy, indicating the formation of a predominantly 2H-PbI2 polytype. This work presents the first case of fully isolated, fully characterized solid nanoparticles of PbI2. It also presents XRD and Raman spectrum for the first time for PbI2 nanoparticles of intermediate quantum confinement.

A review of polytypism in lead iodide

“…Indeed, it is a model system for general inquiries involving nanotechnology research [13]. Finally, the synthesis and characterization of solid nanoparticles of PbI2 has been reported [22].…”

“…Crystal growth conditions are very important [18]. The great variety of ways of preparing PbI2 can be found elsewhere [19,22,39,40, and references therein].…”

Correction: A review of polytypism in lead iodide

“…Indeed, it is a model system for general inquiries involving nanotechnology research [13]. Finally, the synthesis and characterization of solid nanoparticles of PbI 2 has been reported [22].…”

Points to Ponder in the Study of Cadmium Iodide

“…Recently, Kasi et.al. [2] has reported the fabrication and characterization of PbI 2 nanocrystals. They have reported 2H polytype and some presence of 4H.…”