Sinteza şi proprietăţile optice ale soluţiilor coloidale de nanocristalele de PbS

Abstract

The peculiarities of photoluminescence (PL) and optical absorption spectra of PbS nanocrystals (NC) were investigated. The PbS NCs were obtained in chloroform as well as aqueous colloidal solutions using different technologic conditions. PL spectrum consists of relatively narrow excitonic band with maximum located at 0.85 – 1.3 eV in dependence on the NCs size. It was shown that the Stokes shift in PL and optical absorption spectra increases from 30 meV to 225 meV at decreasing of NCs size from 5.1 nm to 2.9 nm.