Understanding the journey of dopant copper ions in atomically flat colloidal nanocrystals of CdSe nanoplatelets using partial cation exchange reactions

Manoj Sharma, Murat Olutas, Aydan Yeltik, Yusuf Kelestemur, Ashma Sharma, Savas Delikanli, Burak Guzelturk, Kivanc Gungor, James R. McBride, Hilmi Volkan Demir

Research output: Contribution to journalArticleResearchpeer-review

51 Citations (Scopus)

Abstract

Unique electronic and optical properties of doped semiconductor nanocrystals (NCs) have widely stimulated a great deal of interest to explore new effective synthesis routes to achieve controlled doping for highly efficient materials. In this work, we show copper doping via postsynthesis partial cation exchange (CE) in atomically flat colloidal semiconductor nanoplatelets (NPLs). Here chemical reactivity of different dopant precursors, reaction kinetics, and shape of seed NPLs were extensively elaborated for successful doping and efficient emission. Dopant-induced Stokes-shifted and tunable photoluminescence emission (640 to 830 nm) was observed in these Cu-doped CdSe NPLs using different thicknesses and heterostructures. High quantum yields (reaching 63%) accompanied by high absorption cross sections (>2.5 times) were obtained in such NPLs compared to those of Cu-doped CdSe colloidal quantum dots (CQDs). Systematic tuning of the doping level in these two-dimensional NPLs provides an insightful understanding of the chemical dopant based orbital hybridization in NCs. The unique combination of doping via the partial CE method and precise control of quantum confinement in such atomically flat NPLs originating from their magic-sized vertical thickness exhibits an excellent model platform for studying photophysics of doped quantum confined systems.

Original languageEnglish
Pages (from-to)3265-3275
Number of pages11
JournalChemistry of Materials
Volume30
Issue number10
DOIs
Publication statusPublished - 22 May 2018
Externally publishedYes

Cite this