Electronic Structure and Elemental Composition of the Lead Sulfide Colloidal Quantum Dots Depending on the Types of Ligand and Post-Treatment

Journal of the Korean Chemical Society

Jeong Won Kim¹  Tae Gun Kim¹  Hyekyoung Choi¹  Sohee Jeong¹ 

关键词: Colloidal quantum dot;    Hybrid ligand;    Electronic structure;    Composition analysis;    Ozone treatment;   

DOI  :  

学科分类：化学（综合）

来源: Korean Chemical Society

【 摘 要 】

Thin films of lead sulfide colloidal quantum dots (CQDs) of 2.8 nm in diameter are fabricated and their surfaces are passivated by 3-mercaptopropionic acid (MPA) ligand or hybrid type (MPA+CdCl2) ligand, respectively. The changes in valence band electronic structure and atomic composition of each PbS CQD film upon post-treatment such as air, N2 annealing or UV/Ozone have been studied by photoelectron spectroscopy. The air annealing makes the CQD fermi level to move toward the valence band leading to “p-type doping” regardless of ligand type. The UV/Ozone post-treatment generates Pb(OH)2, PbSOx and PbO on both CQD surfaces. But the amount of the PbO has been reduced in hybrid type ligand case, especially. That is probably because the extra Pb cations in (111) surface are additionally passivated by Cl2 ligand, which limits the reaction between the Pb cation and ozone.

【 授权许可】

Unknown