Abstract

PORTILLO-MORENO, O. et al. Growth of doped PbS:Co²⁺ nanocrystals by Chemical Bath. Rev. mex. fis. [online]. 2016, vol.62, n.5, pp.456-460. ISSN 0035-001X.

Nanocrystalline PbS films grown by chemical bath at T = 40 ± 2 oC onto glass slides were modified by in situ Co2+ -doping and their structural and optical properties were examined. By FT-IR spectra, a sharp stretching mode can be seen at ~1384 cm-1 due to the vibration mode of $\mathrm{C}{\mathrm{O}}_3^2$ ions. XRD patterns shown the growth on the zinc blende crystalline face. The grain size was determined by using X-rays diffractograms and was found at ~28 nm and ~13 - 25 nm for undoped and doped samples, respectively. Optical absorption spectra was used for calculating the energy band gap, and displayed a shift in the ~1:21 - 2:21 eV range, associated with quantum confinement effect. Raman peaks at ~ 210, 271, and 451 cm-1, corresponding to a 1LO phonon mode, a two-phonon process, and a 2LO phonon mode respectively were also recorded. The surface and grain size of the films were measured by AFM studies.

Keywords : Thin films; nanocrystals; quantum; confinement effect; doping.

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