A quantum dot composition of an embodiment includes: a quantum dot; a ligand combined with a surface of the quantum dot; and a ligand scavenger having a nucleophilic reaction group.

Use of transition metal complexes of the formula (I) in organic light-emitting diodes ##STR00001## where: M.sup.1 is a metal atom; carbene is a carbene ligand; L is a monoanionic or dianionic ligand; K is an uncharged monodentate or bidentate ligand selected from the group consisting of phosphines; CO; pyridines; nitriles and conjugated dienes which form a π complex with M.sup.1; n is the number of carbene ligands and is at least 1; m is the number of ligands L, where m can be 0 or ≥1; o is the number of ligands K, where o can be 0 or ≥1; where the sum n+m+o is dependent on the oxidation state and coordination number of the metal atom and on the denticity of the ligands carbene, L and K and also on the charge on the ligands carbene and L, with the proviso that n is at least 1, and also
an OLED comprising these transition metal complexes, a light-emitting layer comprising these transition metal complexes, OLEDs comprising this light-emitting layer, devices comprising an OLED according to the present invention, and specific transition metal complexes comprising atb least two carbene ligands.

Herein are described two-dimensional metal organic frameworks (2D MOFs). The 2D MOFs includes a plurality of multivalent metals or metal ions and a plurality of multidentate ligands arranged to form a crystalline structure having a lateral size of at least about 2.5 μm and a thickness of less than about 5 nm. Herein are also described methods for preparing the 2D MOFs. The 2D MOFs can be used, for example, in electrochromic devices such as smart windows and flexible displays.

An object of the present invention is to provide a novel electrochromic device (ECD). Disclosed is an electrochromic device (ECD) comprising two metal-complex-based electrochromic thin films individually acting as a working electrode and a counter electrode; (i) one of the two metal-complex-based electrochromic thin films being a film of a cathodically coloring metallo-supramolecular polymer comprising at least one organic ligand having a plurality of metal coordination positions and a metal ion of at least one transition metal and/or lanthanoid metal with the at least one organic ligand and the metal ion being arranged alternately, and the other of the two metal-complex-based electrochromic thin films being a film of an anodically coloring metal hexacyanoferrate (MHCF) represented by the formula: M(II).sub.3[Fe(III)CN.sub.6].sub.2 (where M=Fe, Ni or Zn), and (ii) the electrochromic device having a first conducting substrate; the film of the cathodically coloring metallo-supramolecular polymer; an electrolyte; the film of the anodically coloring metal hexacyanoferrate (MHCF); and a second conducting substrate being arranged in this order.

Use of transition metal complexes of the formula (I) in organic light-emitting diodes

##STR00001## where: M.sup.1 is a metal atom; carbene is a carbene ligand; L is a monoanionic or dianionic ligand; K is an uncharged monodentate or bidentate ligand selected from the group consisting of phosphines; CO; pyridines; nitriles and conjugated dienes which form a π complex with M.sup.1; n is the number of carbene ligands and is at least 1; m is the number of ligands L, where m can be 0 or ≥1; is the number of ligands K, where o can be 0 or ≥1; where the sum n+m+o is dependent on the oxidation state and coordination number of the metal atom and on the denticity of the ligands carbene, L and K and also on the charge on the ligands carbene and L, with the proviso that n is at least 1, and also
an OLED comprising these transition metal complexes, a light-emitting layer comprising these transition metal complexes, OLEDs comprising this light-emitting layer, devices comprising an OLED according to the present invention, and specific transition metal complexes comprising at least two carbene ligands.

New organic materials having polyaromatic structure containing boron and high triplet energy are disclosed. The high triplet energy materials are useful as host materials in PHOLEDs and improve device quantum efficiency and stability.

Complexes and devices, such as organic light emitting devices and full color displays, including a compound of the formula wherein: M is Pd.sup.2+, Ir.sup.+, Rh.sup.+, or Au.sup.3+; each of V.sup.1, V.sup.2, V.sup.3, and V.sup.4 is coordinated to M and is independently N, C, P, B, or Si; each of L.sup.1, L.sup.2, L.sup.3, and L.sup.4 is independently a substituted or unsubstituted aryl, cycloalkyl, cycloalkenyl, heterocyclyl, heteroaryl, carbene, or N-heterocyclic carbene; and Z is O, S, NR, CR.sub.2, SiR.sub.2, BR, PR, where each R is independently substituted or unsubstituted C1-C4 alkyl or substituted or unsubstituted aryl.

Use of transition metal complexes of the formula (I) in organic light-emitting diodes ##STR00001## where: M.sup.1 is a metal atom; carbene is a carbene ligand; L is a monoanionic or dianionic ligand; K is an uncharged monodentate or bidentate ligand selected from the group consisting of phosphines; CO; pyridines; nitriles and conjugated dienes which form a π complex with M.sup.1; n is the number of carbene ligands and is at least 1; m is the number of ligands L, where m can be 0 or ≧1; o is the number of ligands K, where o can be 0 or ≧1; where the sum n+m+o is dependent on the oxidation state and coordination number of the metal atom and on the denticity of the ligands carbene, L and K and also on the charge on the ligands carbene and L, with the proviso that n is at least 1, and also
an OLED comprising these transition metal complexes, a light-emitting layer comprising these transition metal complexes, OLEDs comprising this light-emitting layer, devices comprising an OLED according to the present invention, and specific transition metal complexes comprising at least two carbene ligands.

Provided is a polymer compound useful for production of a light emitting device excellent in external quantum yield. The polymer compound includes a constitutional unit represented by the formula (1):

##STR00001##

wherein a.sup.1 and a.sup.2 represent 0 or 1, Ar.sup.A1 and Ar.sup.A3 represent an arylene group or the like, and in each of Ar.sup.A1 and Ar.sup.A3 at least one atom adjacent to an atom forming a bond to the constitutional unit adjacent to the each of Ar.sup.A1 and Ar.sup.A3 has an alkyl group or the like as a substituent, Ar.sup.A2 represents a phenylene group, Ar.sup.A4 represents an arylene group or the like, R.sup.A1, R.sup.A2 and R.sup.A3 represent an aryl group or the like, and when a.sup.2 is 0, R.sup.A1 represents an aryl group in which two or more rings are condensed (the number of carbon atoms constituting the rings of the aryl group is 10 or more) or the like.

Disclosed are nanostructures comprising Ag, In, Ga, and S and a shell comprising Ag, Ga and S, wherein the nanostructures have a peak wavelength emission of 480-545 nm and wherein at least about 80% of the emission is band-edge emission. Also disclosed are methods of making the nanostructures.