Determination of band alignment of core/shell colloidal CdSe/CdS quantum dots, by optical and X-ray photo-electron spectroscopies
Optical properties of multilayer semi-conductor nano-emitters are crucially dependent on the relative energy levels of their different components. For core/shell quantum dots, the relative energy difference between conduction band edge of core and shell materials induces, depending on its value, eit...
Saved in:
| Main Authors: | , , , , , , , , , |
|---|---|
| Format: | Article |
| Language: | English |
| Published: |
Elsevier
2025-03-01
|
| Series: | Materials Today Quantum |
| Subjects: | |
| Online Access: | http://www.sciencedirect.com/science/article/pii/S2950257825000022 |
| Tags: |
Add Tag
No Tags, Be the first to tag this record!
|
| Summary: | Optical properties of multilayer semi-conductor nano-emitters are crucially dependent on the relative energy levels of their different components. For core/shell quantum dots, the relative energy difference between conduction band edge of core and shell materials induces, depending on its value, either a confinement of the electron within the core or a delocalization of its wave function within the whole quantum dot. This results in drastic consequences on the energy and the oscillator strength of the transitions. Surprisingly, the literature currently lacks a definitive value for this energy difference, called offset, between the conduction band edge of CdSe and CdS materials. Here, we develop a theoretical model expressing energy levels and considering quantum dot dimension, core/shell interface pressure, ligands and allowing to reliably determine the conduction band offset. Its value is determined experimentally using our model and both optical and X-ray photoelectron (XPS) spectroscopies. |
|---|---|
| ISSN: | 2950-2578 |