Size Determination in Chemically Grown PbS Nano Particles Using Different Theoretical Approach

Chemical bath method is adopted for growth of lead sulfide nano particles in methanolic solution of Pb(No-3)(2). Sulfur exchange is achieved by the controlled reaction of Na2S. The optical absorption studies have been done for obtained colloidal solution. The prepared particles are characterized by UV/Visible absorption spectra in the range 700-250 nm and the corresponding energy band gaps have been calculated assuming the effective masses of the electrons and holes in the nano particles to be same as that of bulk. The particle size has been determined by using the Wang Mahler and Brus L.E. Theoretical approaches. It is found that without using any capping agent the band gap of the compound gradually increases as the size of the particle decreases.

Automated summary

The chemical bath method is used to grow lead sulfide nanoparticles in a methanolic solution of Pb(NO3)2, and sulfur exchange is achieved through the controlled reaction of Na2S. The optical absorption of the obtained colloidal solution is studied. The prepared particles are characterized by UV/Visible absorption spectra, and the energy band gaps are calculated based on assuming the same effective masses of electrons and holes in the nanoparticles as in bulk. The particle size is determined using theoretical approaches. It is found that the band gap of the compound gradually increases as the particle size decreases without using any capping agent.