A High Quantum Efficiency Preserving Approach to Ligand Exchange on Lead Sulfide Quantum Dots and Interdot Resonant Energy Transfer

作者：Lingley Zachary; Lu Siyuan; Madhukar Anupam^*

来源：Nano Letters, 2011, 11(7): 2887-2891.

DOI：10.1021/nl201351f

• Quantum dot
• ligand exchange
• energy transfer
• lead sulfide
• quantum efficiency

We present a new approach to ligand exchange on lead sulfide (PbS) quantum dots (QDs) in which the QDs are reacted with preformed Pb cation-ligand exchange units designed to promote reactions that replace surface Pb and oleate groups on the as-grown QDs. This process introduces negligible surface defects as the high quantum efficiency (similar to 55%) of the as-grown QDs is maintained. Infrared spectroscopy and electron microscopy are used to confirm the replacement of ligands and time-resolved photoluminescence to demonstrate the expected inverse sixth power dependence of the nonradiative resonant energy transfer rate on inter-QD spacing.

• 出版日期2011-7