Quantum dot device and electronic device including the same
A quantum dot device and an electronic device including the device are provided. The quantum dot device includes a first electrode and a second electrode, a quantum dot layer disposed between the first electrode and the second electrode, and a hole auxiliary layer disposed between the quantum dot layer and the first electrode, wherein the hole auxiliary layer includes nickel oxide and a self-assembled monolayer disposed between the hole auxiliary layer and the quantum dot layer, the self-assembled monolayer including an organic compound represented by Chemical Formula 1.
1 . A quantum dot device, comprising
a first electrode and a second electrode,
a quantum dot layer disposed between the first electrode and the second electrode,
a hole auxiliary layer disposed between the quantum dot layer and the first electrode, wherein the hole auxiliary layer comprises NiO x , wherein 1.1≤x≤1.5, and
a self-assembled monolayer disposed between the hole auxiliary layer and the quantum dot layer, the self-assembled monolayer comprising an organic compound represented by Chemical Formula 1:
wherein, in Chemical Formula 1,
A is an anionic anchor group,
R a and R b are each independently hydrogen, deuterium, a C1 to C10 alkyl group, or a C1 to C10 fluoroalkyl group,
n is an integer from 0 to 3,
Cy is a substituted or unsubstituted C6 to C30 aryl group, a substituted or unsubstituted C2 to C30 heteroaryl group, a substituted or unsubstituted C3 to C30 cycloalkyl group, or a substituted or unsubstituted C2 to C30 heterocycloalkyl group, and
X is a hydrophobic substituted or unsubstituted C1 to C20 alkyl group, F, Cl, or I.
2 . The quantum dot device of claim 1 , wherein the compound represented by Chemical Formula 1 comprises an organic compound represented by Chemical Formula 1-1:
wherein, in Chemical Formula 1-1,
A is an anionic anchor group,
R a and R b are each independently hydrogen, deuterium, a C1 to C10 alkyl group, or a C1 to C10 fluoroalkyl group,
n is an integer from 0 to 3,
R c is hydrogen, deuterium, or a C1 to C6 alkyl group,
optionally, a CH of the benzene ring is replaced by N,
m is an integer from 1 to 4, and
X is a hydrophobic substituted or unsubstituted C1 to C20 alkyl group, F, Cl, or I.
3 . The quantum dot device of claim 1 , wherein the anionic anchor group A comprises a carboxyl group, a sulfonic acid group, a phosphoric acid group, a phosphonic acid group, or a salt thereof.
4 . The quantum dot device of claim 1 , wherein the hole auxiliary layer has a thickness of about 10 nanometers to about 100 nanometers.
5 . The quantum dot device of claim 1 , wherein a bandgap energy of the hole auxiliary layer is in a range of about 3.0 electronvolts to about 5.0 electronvolts.
6 . The quantum dot device of claim 1 , wherein an energy level of a valence band of the hole auxiliary layer is between a work function of the first electrode and a highest occupied molecular orbital energy level of the quantum dot layer.
7 . The quantum dot device of claim 1 , wherein an energy level of a valence band of the hole auxiliary layer is equal to or less than a highest occupied molecular orbital energy level of the quantum dot layer, and a difference between the energy level of the valence band of the hole auxiliary layer and the highest occupied molecular orbital energy level of the quantum dot layer is less than or equal to about 1.0 electronvolt.
8 . The quantum dot device of claim 1 , wherein an energy level of a conduction band of the hole auxiliary layer is less than a lowest unoccupied molecular orbital energy level of the quantum dot layer.
9 . The quantum dot device of claim 1 , wherein an energy level of a conduction band of the hole auxiliary layer is greater than a lowest unoccupied molecular orbital energy level of the quantum dot layer, and a difference between the energy level of the conduction band of the hole auxiliary layer and the lowest unoccupied molecular orbital energy level of the quantum dot layer is greater than or equal to about 0.5 eV.
10 . The quantum dot device of claim 1 , wherein a ratio of a thickness of the self-assembled monolayer to a thickness of the hole auxiliary layer 12 is in a range of about 0.01:1 to about 0.5:1.
11 . A quantum dot device, comprising
a first electrode and a second electrode,
a quantum dot layer disposed between the first electrode and the second electrode,
a hole auxiliary layer disposed between the quantum dot layer and the first electrode, wherein the hole auxiliary layer comprises nickel oxide,
a self-assembled monolayer disposed between the hole auxiliary layer and the quantum dot layer, and
an electron auxiliary layer comprising inorganic nanoparticles or an organic material,
wherein the self-assembled monolayer comprises an organic compound represented by Chemical Formula 1:
wherein, in Chemical Formula 1,
A is an anionic anchor group,
R a and R b are each independently hydrogen, deuterium, a C1 to C10 alkyl group, or a C1 to C10 fluoroalkyl group,
n is an integer from 0 to 3,
Cy is a substituted or unsubstituted C6 to C30 aryl group, a substituted or unsubstituted C2 to C30 heteroaryl group, a substituted or unsubstituted C3 to C30 cycloalkyl group, or a substituted or unsubstituted C2 to C30 heterocycloalkyl group, and
X is a hydrophobic substituted or unsubstituted C1 to C20 alkyl group or a halogen.
12 . The quantum dot device of claim 11 , wherein the inorganic nanoparticles comprise metal oxide nanoparticles represented by Zn 1-x Q x O, wherein Q is a metal other than Zn, and 0≤x<0.5.
13 . A quantum dot device, comprising
a first electrode and a second electrode,
a quantum dot layer disposed between the first electrode and the second electrode,
a first hole auxiliary layer disposed between the quantum dot layer and the first electrode, wherein the first hole auxiliary layer comprises nickel oxide,
a second hole auxiliary layer comprising an organic material between the first hole auxiliary layer and the quantum dot layer, and
a self-assembled monolayer disposed between the first hole auxiliary layer and the quantum dot layer,
wherein the self-assembled monolayer comprises an organic compound represented by Chemical Formula 1:
wherein, in Chemical Formula 1,
A is an anionic anchor group,
R a and R b are each independently hydrogen, deuterium, a C1 to C10 alkyl group, or a C1 to C10 fluoroalkyl group,
n is an integer from 0 to 3,
Cy is a substituted or unsubstituted C6 to C30 aryl group, a substituted or unsubstituted C2 to C30 heteroaryl group, a substituted or unsubstituted C3 to C30 cycloalkyl group, or a substituted or unsubstituted C2 to C30 heterocycloalkyl group, and
X is a hydrophobic substituted or unsubstituted C1 to C20 alkyl group or a halogen.
14 . The quantum dot device of claim 1 , wherein the quantum dot layer comprises a cadmium-free Group III-V semiconductor compound.
15 . An electronic device comprising the quantum dot device of claim 1 .
16 . The quantum dot device of claim 1 , wherein X is a C1 to C20 fluoroalkyl group or a C1 to C20 perfluoroalkyl group.
17 . The quantum dot device of claim 1 , wherein X is F.
18 . The quantum dot device of claim 1 , wherein X is Cl.