TY - JOUR
T1 - Orthogonal colloidal quantum dot inks enable efficient multilayer optoelectronic devices
AU - Lee, Seungjin
AU - Choi, Min Jae
AU - Sharma, Geetu
AU - Biondi, Margherita
AU - Chen, Bin
AU - Baek, Se Woong
AU - Najarian, Amin Morteza
AU - Vafaie, Maral
AU - Wicks, Joshua
AU - Sagar, Laxmi Kishore
AU - Hoogland, Sjoerd
AU - de Arquer, F. Pelayo García
AU - Voznyy, Oleksandr
AU - Sargent, Edward H.
N1 - Publisher Copyright:
© 2020, The Author(s).
PY - 2020/12/1
Y1 - 2020/12/1
N2 - Surface ligands enable control over the dispersibility of colloidal quantum dots (CQDs) via steric and electrostatic stabilization. Today’s device-grade CQD inks have consistently relied on highly polar solvents: this enables facile single-step deposition of multi-hundred-nanometer-thick CQD films; but it prevents the realization of CQD film stacks made up of CQDs having different compositions, since polar solvents redisperse underlying films. Here we introduce aromatic ligands to achieve process-orthogonal CQD inks, and enable thereby multifunctional multilayer CQD solids. We explore the effect of the anchoring group of the aromatic ligand on the solubility of CQD inks in weakly-polar solvents, and find that a judicious selection of the anchoring group induces a dipole that provides additional CQD-solvent interactions. This enables colloidal stability without relying on bulky insulating ligands. We showcase the benefit of this ink as the hole transport layer in CQD optoelectronics, achieving an external quantum efficiency of 84% at 1210 nm.
AB - Surface ligands enable control over the dispersibility of colloidal quantum dots (CQDs) via steric and electrostatic stabilization. Today’s device-grade CQD inks have consistently relied on highly polar solvents: this enables facile single-step deposition of multi-hundred-nanometer-thick CQD films; but it prevents the realization of CQD film stacks made up of CQDs having different compositions, since polar solvents redisperse underlying films. Here we introduce aromatic ligands to achieve process-orthogonal CQD inks, and enable thereby multifunctional multilayer CQD solids. We explore the effect of the anchoring group of the aromatic ligand on the solubility of CQD inks in weakly-polar solvents, and find that a judicious selection of the anchoring group induces a dipole that provides additional CQD-solvent interactions. This enables colloidal stability without relying on bulky insulating ligands. We showcase the benefit of this ink as the hole transport layer in CQD optoelectronics, achieving an external quantum efficiency of 84% at 1210 nm.
UR - http://www.scopus.com/inward/record.url?scp=85091370471&partnerID=8YFLogxK
U2 - 10.1038/s41467-020-18655-7
DO - 10.1038/s41467-020-18655-7
M3 - Article
C2 - 32968078
AN - SCOPUS:85091370471
SN - 2041-1723
VL - 11
JO - Nature Communications
JF - Nature Communications
IS - 1
M1 - 4814
ER -