Quantum dot, composition for preparing quantum dot composite, quantum dot composite, and display panel
A quantum dot, a quantum dot composite including the quantum dot, a composition for preparing the quantum dot composite, a display panel including the quantum dot composite, and an electronic apparatus including the display panel. The quantum dot includes a semiconductor nanocrystal core including indium and phosphorus, the semiconductor nanocrystal core having an emission peak wavelength from about 600 nm to about 650 nm, or an emission peak wavelength from about 500 nm to about 550 nm, and an area of a peak from about 400° C. to about 500° C. is 0.17 times to 0.5 times relative to an area of a peak from about 200° C. to about 300° C. in a thermogravimetric analysis (TGA) graph as determined with a differential scanning calorimeter (DSC).
1 . A quantum dot comprising
a semiconductor nanocrystal core comprising indium and phosphorus,
the quantum dot having an emission peak wavelength from about 600 nm to about 650 nm, or an emission peak wavelength from about 500 nm to about 550 nm,
wherein the quantum dot exhibits an area of a peak from about 400° C. to about 500° C. that is about 0.17 times to about 0.5 times relative to an area of a peak from about 200° C. to about 300° C. in a thermogravimetric analysis graph as determined with a differential scanning calorimeter.
2 . The quantum dot of claim 1 , wherein in the thermogravimetric analysis graph of the quantum dots, an area of a peak from about 200° C. to about 400° C. is greater than or equal to about 40% of a total peak area of the thermogravimetric analysis graph.
3 . The quantum dot of claim 1 , wherein the quantum dot further comprise a semiconductor nanocrystal shell disposed on the semiconductor nanocrystal core, the nanocrystal shell comprising zinc and selenium.
4 . The quantum dot of claim 3 , wherein the semiconductor nanocrystal shell further comprises sulfur.
5 . The quantum dot of claim 4 , wherein the semiconductor nanocrystal shell comprises a first semiconductor nanocrystal shell disposed on the semiconductor nanocrystal core, the first semiconductor nanocrystal shell comprising zinc and selenium; and a second semiconductor nanocrystal shell disposed on the first semiconductor nanocrystal shell, the second semiconductor nanocrystal shell comprising zinc and sulfur.
6 . The quantum dot of claim 1 , wherein the quantum dot further comprises an organic compound disposed on a surface of the quantum dot, wherein the organic compound comprises a carboxyl group and/or a thiol group bound to the surface of the quantum dot.
7 . The quantum dot of claim 6 , wherein the portion of the organic compound bound to the surface of the quantum dot is the carboxyl group, and the organic compound is represented by RCOOH, RCOOR′, or a combination thereof, wherein R and R′ are each independently a substituted or unsubstituted C1 to C30 saturated or unsaturated aliphatic hydrocarbon group, a substituted or unsubstituted C3 to C30 saturated or unsaturated alicyclic hydrocarbon group, a substituted or unsubstituted C6 to C30 aromatic hydrocarbon group, or a combination thereof.
8 . The quantum dot of claim 6 , wherein the organic compound comprises a thiol group bound to the surface of the quantum dot at a terminal end; the organic compound including an organic group of a substituted or unsubstituted C1 to C30 saturated or unsaturated aliphatic hydrocarbon group, a substituted or unsubstituted C3 to C30 saturated or unsaturated alicyclic hydrocarbon group, a substituted or unsubstituted C6 to a C30 aromatic hydrocarbon group, or a combination thereof, at another terminal end; and —{(C n H 2n ) a —O}— wherein n and a are each independently an integer of greater than or equal to 1; and optionally —(C═O)O—, a substituted or unsubstituted C1 to C30 alkylene group, or a combination thereof, disposed between the thiol group and the organic group.
9 . The quantum dot of claim 6 , wherein the portion of the organic compound bound to the surface of the quantum dot is a thiol group, and the organic compound is represented by Chemical Formula 1:
R—O—{(C n H 2n ) a O} b —(C n H 2n ) c —(O) d —(C═O) e —(O) f —(C n H 2n ) g —(CHSH) h —(C n H 2n ) i —[(C═O)O{(C n H 2n ) j O} k R] l —(SH) m Chemical Formula 1
wherein, in Chemical Formula 1,
R is a substituted or unsubstituted C1 to C30 saturated or unsaturated aliphatic hydrocarbon group, a substituted or unsubstituted C3 to C30 saturated or unsaturated alicyclic hydrocarbon group, a substituted or unsubstituted C6 to C30 aromatic hydrocarbon group, or a combination thereof,
n is an integer of greater than or equal to 1,
a, b, c, g, i, j, and k are each independently an integer of greater than or equal to 0,
d, e, f, h, l, and m are all 0 or 1, provided that h and m are not both 0,
when h and m are both 1, l is 0, and
when h and l are both 1, m is 0.
10 . The quantum dot of claim 6 , wherein the organic compound in which the portion bound to the surface of the quantum dots is the thiol group is represented by one or more of Chemical Formula 1-1 to Chemical Formula 1-6:
wherein, in Chemical Formula 1-1 to Chemical Formula 1-6,
R 1 to R 7 are each independently a substituted or unsubstituted C1 to C10 alkyl group or a substituted or unsubstituted C6 to C20 aryl group,
L 1 to L 16 are each independently a substituted or unsubstituted C1 to C10 alkylene group, and
n1 to n7 are each independently an integer of 0 to 10.
11 . The quantum dot of claim 3 , wherein a weight ratio of a weight of zinc to a weight of indium is from about 10:1 to about 30:1, and a weight ratio of a weight of selenium to a weight of indium is from about 2.9:1 to about 20:1.
12 . A composition for preparing a quantum dot composite, comprising
the quantum dot of claim 1 , and at least one of a polymerizable monomer comprising a carbon-carbon unsaturated bond and a dispersant.
13 . The composition of claim 12 , further comprising a thiol compound having at least one thiol group at a terminal end, metal oxide particulates, or a combination thereof.
14 . The composition of claim 12 , wherein
the dispersant is an organic compound comprising a carboxyl group, and
the dispersant comprises
a combination of monomers including a first monomer having a carboxyl group and a carbon-carbon double bond, a second monomer having a carbon-carbon double bond and a hydrophobic moiety and not having a carboxyl group, and optionally, a third monomer having a carbon-carbon double bond and a hydrophilic moiety and not having a carboxyl group, or a copolymer thereof;
a multi-aromatic ring-containing polymer having a backbone in which two aromatic rings in a main chain are bonded to quaternary carbon atoms that are constituent atoms of other cyclic moieties, and having a carboxyl group; or
a combination thereof.
15 . The composition of claim 13 , wherein the metal oxide particulates comprise TiO 2 , SiO 2 , BaTiO 3 , Ba 2 TiO 4 , ZnO, or a combination thereof.
16 . The composition of claim 13 , wherein the thiol compound comprises a compound represented by Chemical Formula 2:
wherein, in Chemical Formula 2,
R 1 is hydrogen; a substituted or unsubstituted C1 to C30 linear or branched alkyl group; a substituted or unsubstituted C6 to C30 aryl group; a substituted or unsubstituted C3 to C30 heteroaryl group; a substituted or unsubstituted C3 to C30 cycloalkyl group; a substituted or unsubstituted C3 to C30 heterocycloalkyl group; a C1 to C10 alkoxy group; a hydroxy group; —NH 2 ; a substituted or unsubstituted C1 to C30 amine group (—NRR′, wherein R and R′ are each independently hydrogen or a C1 to C30 linear or branched alkyl group and not hydrogen at the same time); an isocyanate group; a halogen; —ROR′ wherein R is a substituted or unsubstituted C1 to C20 alkylene group and R′ is hydrogen or a C1 to C20 linear or branched alkyl group; an acyl halide group (—RC(═O)X, wherein R is a substituted or unsubstituted C1 to C20 alkylene group and X is a halogen); —C(═O)OR′ (wherein R′ is hydrogen or a C1 to C20 linear or branched alkyl group); —ON; or —C(═O)ORR′ or —C(═O)ONRR′, wherein R and R′ are each independently hydrogen or a C1 to C20 linear or branched alkyl group,
L 1 is a carbon atom, a substituted or unsubstituted C1 to C30 alkylene group, a substituted or unsubstituted C1 to C30 alkylene group in which at least one methylene (—CH 2 —) is replaced by sulfonyl (—SO 2 —), carbonyl (CO), ether bond (—O—), sulfide group (—S—), sulfoxide group (—SO—), ester group (—C(═O)O—), amide group (—C(═O)NR—, wherein R is hydrogen or a C1 to C10 linear or branched alkyl group), or a combination thereof, a substituted or unsubstituted C3 to C30 cycloalkylene group, a substituted or unsubstituted C6 to C30 arylene group, a substituted or unsubstituted C3 to C30 heteroarylene group, or a substituted or unsubstituted C3 to C30 heterocycloalkylene group,
Y 1 is a single bond; a substituted or unsubstituted C1 to C30 alkylene group; a substituted or unsubstituted C2 to C30 alkenylene group; or a C1 to C30 alkylene group or a C2 to C30 alkenylene group in which at least one methylene (—CH 2 —) is replaced by sulfonyl (—S(═O) 2 —), carbonyl (—C(═O)—), ether bond (—O—), sulfide group (—S—), sulfoxide group (—S(═O)—), ester group (—C(═O)O—), amide group (—C(═O)NR—, wherein R is hydrogen or a C1 to C10 linear or branched alkyl group), imine group (—NR—, wherein R is hydrogen or a C1 to C10 linear or branched alkyl group), or a combination thereof,
m is an integer of greater than or equal to 1,
k1 is 0 or an integer of greater than or equal to 1 and k2 is an integer of greater than or equal to 1,
a sum of m and k2 is an integer of greater than or equal to 3,
m does not exceed the valence of Y 1 , and
a sum of k1 and k2 does not exceed the valence of L 1 .