Published online by Cambridge University Press: 19 April 2012
We investigated the temperature dependence of the Stokes shift of PbS quantum dots (diameter 4.7 nm) deposited from solution on glass using a specially designed apparatus. By measuring the thermal alteration of the optical absorbance and photoluminescence in the range of 5 K – 300 K, we demonstrate that the Stokes shift shrinks from 135 meV at 5 K to 62 meV at 300 K. Extrapolation of the data presented predict an elimination temperature of the Stokes shift of about 460 K, corresponding to the thermal energy of the sum of prominent PbS phonon energies.