Quantum dot and preparation method therefor, quantum dot light-emitting device, and display apparatus
Disclosed are a quantum dot and a preparation method therefor, a quantum dot light-emitting device, and a display apparatus. The quantum dot includes a core structure and a shell structure that surrounds the core structure, wherein the material of the outermost shell in the shell structure includes an electron transport material and a hole transport material.
1 . A quantum dot, comprising a core structure and a shell structure surrounding the core structure, wherein a material of an outermost shell in the shell structure comprises an electron transport material and a hole transport material, and the outermost shell constitutes an outermost layer of the quantum dot;
wherein the outermost shell comprises a plurality of electron transport material grains and a plurality of hole transport material grains, and the electron transport material grains and the hole transport material grains are dispersed and spaced with each other.
2 . The quantum dot according to claim 1 , wherein the shell structure comprises the outermost shell and an inner shell located between the outermost shell and the core structure.
3 . The quantum dot according to claim 2 , wherein a material of the inner shell comprises a binary compound semiconductor material.
4 . The quantum dot according to claim 3 , wherein the material of the inner shell comprises one or a combination of ZnS, ZnSe, CdS or CdSe.
5 . The quantum dot according to claim 1 , wherein the electron transport material is an inorganic material, and/or, the hole transport material is an inorganic material.
6 . The quantum dot according to claim 5 , wherein when the electron transport material is the inorganic material, the electron transport material comprises one or a combination of ZnO, Al 2 O 3 , TiO 2 , ZrO 2 , SnO 2 , Nb 2 O 5 , or In 2 O 3 ; and/or,
when the hole transport material is the inorganic material, the hole transport material comprises one or a combination of nickel oxide, tungsten oxide, molybdenum oxide, vanadium oxide, or chromium oxide.
7 . The quantum dot according to claim 1 , wherein a thickness of the outermost shell is 1 nm to 100 nm.
8 . A quantum dot, comprising a core structure and a shell structure surrounding the core structure, wherein a material of an outermost shell in the shell structure comprises an electron transport material and a hole transport material; the outermost shell comprises a plurality of electron transport material grains and a plurality of hole transport material grains, and the electron transport material grains and the hole transport material grains are dispersed and spaced with each other.
9 . A quantum dot light-emitting device, comprising an anode, a hole injection layer, a quantum dot light-emitting layer and a cathode arranged sequentially in a stacked mode, wherein the quantum dot light-emitting layer comprises the quantum dot according to claim 8 .
10 . The quantum dot light-emitting device according to claim 9 , wherein the hole injection layer is in direct contact with the quantum dot light-emitting layer.
11 . A display apparatus, comprising the quantum dot light-emitting device according to claim 9 .
12 . A preparation method for the quantum dot according to claim 8 , comprising:
providing an original quantum dot comprising the core structure and an original shell surrounding the core structure; and
processing the original shell to form the shell structure surrounding the core structure; wherein the material of the outermost shell in the shell structure comprises the electron transport material and the hole transport material; the outermost shell comprises the plurality of electron transport material grains and the plurality of hole transport material grains, and the electron transport material grains and the hole transport material grains are dispersed and spaced with each other.
13 . The preparation method according to claim 12 , wherein the processing the original shell to form the shell structure surrounding the core structure comprises:
partially oxidizing the original shell to form an oxide shell on a surface of the original shell, and an inner shell located between the oxide shell and the core structure; and
performing partial ion exchange on the oxide shell to form the outermost shell with the material comprising the electron transport material and the hole transport material.
14 . The preparation method according to claim 13 , wherein the performing partial ion exchange on the oxide shell comprises:
introducing an exchange reagent of a cation and a ligand into a solution of the quantum dot comprising the oxide shell to achieve partial ion exchange through strength of a coordination capability between the ligand and the cation.
15 . The quantum dot according to claim 8 , wherein the shell structure comprises the outermost shell and an inner shell located between the outermost shell and the core structure.
16 . The quantum dot according to claim 15 , wherein a material of the inner shell comprises a binary compound semiconductor material.
17 . The quantum dot according to claim 16 , wherein the material of the inner shell comprises one or a combination of ZnS, ZnSe, CdS or CdSe.
18 . The quantum dot according to claim 8 , wherein the electron transport material is an inorganic material, and/or, the hole transport material is an inorganic material.
19 . The quantum dot according to claim 18 , wherein when the electron transport material is the inorganic material, the electron transport material comprises one or a combination of ZnO, Al 2 O 3 , TiO 2 , ZrO 2 , SnO 2 , Nb 2 O 5 , or In 2 O 3 ; and/or,
when the hole transport material is the inorganic material, the hole transport material comprises one or a combination of nickel oxide, tungsten oxide, molybdenum oxide, vanadium oxide, or chromium oxide.
20 . The quantum dot according to claim 8 , wherein a thickness of the outermost shell is 1 nm to 100 nm.