Surface depletion effects in bromide-ligated colloidal cadmium selenide nanoplatelets: toward efficient emission at high temperature
The colloidal semiconductor nanoplatelet (NPL) with broad ligand-semiconductor interface is an ideal system for surface science investigation, but the study regarding depletion effects in NPLs remains lacking. Herein we explore such effects in colloidal CdSe NPLs through Br ligation. Apart from im...
Saved in:
Main Authors: | , , , , , , |
---|---|
Other Authors: | |
Format: | Article |
Language: | English |
Published: |
2022
|
Subjects: | |
Online Access: | https://hdl.handle.net/10356/156909 |
Tags: |
Add Tag
No Tags, Be the first to tag this record!
|
Institution: | Nanyang Technological University |
Language: | English |
Summary: | The colloidal semiconductor nanoplatelet (NPL) with broad ligand-semiconductor interface is an ideal system for surface science investigation, but the study regarding
depletion effects in NPLs remains lacking. Herein we explore such effects in colloidal CdSe
NPLs through Br ligation. Apart from improved brightness and red-shifted optical features, we
also experimentally observed abnormal negative thermal quenching phenomena in bromideligated CdSe NPLs over 200 K under a cryogenic environment and up to 383 K under an
ambient environment, which was absent in pristine NPLs. We speculate that the surface
depletion effect shall account for these anomalous phenomena due to the susceptibility of the
surface depletion region on photoexcited carrier concentration and surface condition. The
existence of the depletion layer in NPLs is also validated quantitatively with k·p simulation.
Besides offering an alternative explanation on the red-shifted optical properties of CdSe NPLs
by Br-ligation, our findings pave the new route toward solution-processed NPLs-based
optoelectronics with boosted thermal resistance. |
---|