Size-tunable PbS quantum dots were synthesized using 1-thioglycerol and dithioglycerol as stabilizers via a facile one-step synthetic method. Instead of the traditional organometallic route, in which toxic precursors or solvents might be used, the wet chemical approach demonstrated in this paper is superior in terms of simplicity, use of nontoxic materials, mild synthetic condition and good reproducibility. The resultant PbS quantum dots are monodispersed with particle size ranging from 3 to 5 nanometers. Photoluminescence quantum efficiency of the as-synthetic quantum dots is up to 11.8% and can be maintained by 80% within five weeks with additional capping agents introduced into the storage vessel.

Key words: PbS quantum dot, wet chemical synthesis, photoluminescence, photoluminescence quantum efficiency