In Situ Optical and X-ray Spectroscopy Reveals Evolution toward Mature CdSe Nanoplatelets by Synergetic Action of Myristate and Acetate Ligands

The growth of two-dimensional platelets of the CdX family (X = S, Se, or Te) in an organic solvent requires the presence of both long- and short-chain ligands. This results in nanoplatelets of atomically precise thickness and long-chain ligand-stabilized Cd top and bottom surfaces. The platelets show a bright and spectrally pure luminescence. Despite the enormous interest in CdX platelets for optoelectronics, the growth mechanism is not fully understood. Riedinger et al. studied the reaction without a solvent and showed the favorable role for short-chain carboxylates for growth in two dimensions. Their model, based on the total energy of island nucleation, shows favored side facet growth versus growth on the top and bottom surfaces. However, several aspects of the synthesis under realistic conditions are not yet understood: Why are both short- and long-chain ligands required to obtain platelets? Why does the synthesis result in both isotropic nanocrystals and platelets? At which stage of the reaction is there bifurcation between isotropic and 2D growth? Here, we report an in situ study of the CdSe nanoplatelet reaction under practical synthesis conditions. We show that without short-chain ligands, both isotropic and mini-nanoplatelets form in the early stage of the process. However, most remaining precursors are consumed in isotropic growth. Addition of acetate induces a dramatic shift toward nearly exclusive 2D growth of already existing mini-nanoplatelets. Hence, although myristate stabilizes mini-nanoplatelets, mature nanoplatelets only grow by a subtle interplay between myristate and acetate, the latter catalyzes fast lateral growth of the side facets of the mini-nanoplatelets.

Medienart:

E-Artikel

Erscheinungsjahr:

2022

Erschienen:

2022

Enthalten in:

Zur Gesamtaufnahme - volume:144

Enthalten in:

Journal of the American Chemical Society - 144(2022), 18 vom: 11. Mai, Seite 8096-8105

Sprache:

Englisch

Beteiligte Personen:

van der Bok, Johanna C [VerfasserIn]
Prins, P Tim [VerfasserIn]
Montanarella, Federico [VerfasserIn]
Maaskant, D Nicolette [VerfasserIn]
Brzesowsky, Floor A [VerfasserIn]
van der Sluijs, Maaike M [VerfasserIn]
Salzmann, Bastiaan B V [VerfasserIn]
Rabouw, Freddy T [VerfasserIn]
Petukhov, Andrei V [VerfasserIn]
De Mello Donega, Celso [VerfasserIn]
Vanmaekelbergh, Daniel [VerfasserIn]
Meijerink, Andries [VerfasserIn]

Links:

Volltext

Themen:

0I3V7S25AW
Acetates
Cadmium Compounds
Journal Article
Ligands
Myristates
Myristic Acid
Research Support, Non-U.S. Gov't
Selenium Compounds
Solvents

Anmerkungen:

Date Completed 12.05.2022

Date Revised 16.07.2022

published: Print-Electronic

Citation Status MEDLINE

doi:

10.1021/jacs.2c00423

funding:

Förderinstitution / Projekttitel:

PPN (Katalog-ID):

NLM340109017