Self-assembly of ligand-free PbS nanocrystals into nanorods and their nanosculpturing by electron-beam irradiation

Journal article

A novel method for removing the surface-capping ligand, oleic acid, from PbS nanocrystals synthesized in solution was reported. PbS nanocrystals were prepared at elevated temperatures using oleic acid as a surfactant and octadecene as a noncoordinative high boiling point solvent. All reactions were conducted in a nitrogen atmosphere to minimize the effect of oxygen. 0.76 g of lead acetate 10 mL of octadecene, and 2 mL of oleic acid were heated to 260°C and stirred for 30 minutes to form a clear lead acetate precursor solution. The sulfur precursor solution was added to the lead solution using a glass syringe. The solution turned black, indicating the formation of PbS nanocrystals and was left to react for 10 mm. Transmission electron microscopy (TEM) of the PbS nanocrystals revealed a relatively uniform size distribution with a mean size of 7 nm. Confirmation that the nanocrystals were PbS with the rock-salt crystal structure was obtained from selected-area electron diffraction (SAED).

Authors: Warner, J

• Journal: Advanced Materials
• Volume: 20
• Issue: 4
• Pages: 784-787
• Publication date: 2008-02-18
• DOI: 10.1002/adma.200701799
• EISSN: 1521-4095
• ISSN: 0935-9648
• Language: English