Unravelling kinetic and thermodynamic effects on the growth of gold nanoplates by liquid transmission electron microscopy.
The growth of colloidal nanoparticles is simultaneously driven by kinetic and thermodynamic effects that are difficult to distinguish. We have exploited in situ scanning transmission electron microscopy in liquid to study the growth of Au nanoplates by radiolysis and unravel the mechanisms influencing their formation and shape. The electron dose provides a straightforward control of the growth rate that allows quantifying the kinetic effects on the planar nanoparticles formation. Indeed, we demonstrate that the surface-reaction rate per unit area has the same dose-rate dependent behavior than the concentration of reducing agents in the liquid cell. Interestingly, we also determine a critical supply rate of gold monomers for nanoparticle faceting, corresponding to three layers per second, above which the formation of nanoplates is not possible because the growth is then dominated by kinetic effects. At lower electron dose, the growth is driven by thermodynamic and the formation and shape of nanoplates are directly related to the twin-planes formed during the growth.
†Laboratoire Matériaux et Phénomènes Quantiques, UMR 7162 CNRS/Université Paris - Diderot, 10 rue Alice Domon et Léonie Duquet, 75013 Paris, France.
Damien
D
Alloyeau
†Laboratoire Matériaux et Phénomènes Quantiques, UMR 7162 CNRS/Université Paris - Diderot, 10 rue Alice Domon et Léonie Duquet, 75013 Paris, France.
Walid
W
Dachraoui
†Laboratoire Matériaux et Phénomènes Quantiques, UMR 7162 CNRS/Université Paris - Diderot, 10 rue Alice Domon et Léonie Duquet, 75013 Paris, France.
Yasir
Y
Javed
‡Interfaces Traitements Organisation et Dynamique des Systèmes, UMR7086 CNRS/Université Paris - Diderot, 15, rue Jean-Antoine de Baïf, 75013 Paris, France.
Hannen
H
Belkahla
†Laboratoire Matériaux et Phénomènes Quantiques, UMR 7162 CNRS/Université Paris - Diderot, 10 rue Alice Domon et Léonie Duquet, 75013 Paris, France.
Guillaume
G
Wang
‡Interfaces Traitements Organisation et Dynamique des Systèmes, UMR7086 CNRS/Université Paris - Diderot, 15, rue Jean-Antoine de Baïf, 75013 Paris, France.
Hélène
H
Lecoq
‡Interfaces Traitements Organisation et Dynamique des Systèmes, UMR7086 CNRS/Université Paris - Diderot, 15, rue Jean-Antoine de Baïf, 75013 Paris, France.
Souad
S
Ammar
∥Institut de Physique et Chimie des Matériaux de Strasbourg (IPCMS, UMR 7504 CNRS-UDS), 23 rue du Loess BP 43 F-67034, Strasbourg Cedex 2, France.
Ovidiu
O
Ersen
⊥Department of Chemistry and CeNS, Ludwig-Maximilians-University, Butenandtstrasse 11, 81377 Munich, Germany.
Andreas
A
Wisnet
§Laboratoire Matières et Systèmes Complexes, UMR 7057 CNRS/Université Paris - Diderot, 10 rue Alice Domon et Léonie Duquet, 75013 Paris, France.
Florence
F
Gazeau
†Laboratoire Matériaux et Phénomènes Quantiques, UMR 7162 CNRS/Université Paris - Diderot, 10 rue Alice Domon et Léonie Duquet, 75013 Paris, France.
Christian
C
Ricolleau
Gold nanoplates; dose rate; growth; in situ liquid transmission electron microscopy; kinetic effects; twinning