Non-Injection and Low-Temperature Approach to Colloidal Photoluminescent PbS Nanocrystals with Narrow Bandwidth

Abstract

Colloidal photoluminescent (PL) PbS nanocrystals have attracted a lot of attention in various applications such as bioimaging and optical telecommunications due to their tunable bandgap in the near-infrared region of the electromagnetic spectrum. Hot-injection processes seem to be the best to engineer high-quality PbS nanocrystals. However, there is a limited body of literature documented on the syntheses, with little information on synthetic parameters affecting the optical properties of the product. Moreover, small PbS nanocrystals with large bandgap greater than 1.38 eV (ca. 900 nm) and narrow bandwidth are rarely reported, due to the fact that high-temperature growth in hot-injection processes leads to large nanocrystals rapidly. This manuscript deals with our noninjection and low temperature approach to small PbS nanocrystal ensembles with bandgap in wavelength shorter than 900 nm and with narrow bandwidth; the growth temperature can be as low as room temperature. For our noninjection approach, syste...