Abstract: A light emitting device including a first electrode and a second electrode spaced from each other, and, a light emitting film between the first electrode and the second electrode, wherein the light emitting film has a first surface facing the second electrode and a second surface opposite thereto, the light emitting film includes a quantum dot layer including a plurality of quantum dots and a matrix including a metal chalcogenide, the plurality of quantum dots includes selenium, the matrix covers at least a portion of the quantum dot layer, the metal chalcogenide comprises zinc and sulfur, and in an X-ray photoelectron spectroscopic analysis of the first surface of the light emitting film, a mole ratio of zinc with respect to selenium is greater than or equal to about 2:1 and a mole ratio of sulfur with respect to selenium is greater than or equal to about 1.1:1.

Abstract: A polymer including a structural unit represented by Chemical Formula 1, an electroluminescence device material including the polymer, an electroluminescence device including the polymer or the electroluminescence device material, and an electronic device including the electroluminescence device are provided: In Chemical Formula 1, the definition of each substituent is the same as described in the specification.

Abstract: As a technology capable of improving the durability of an electroluminescent device, for example, luminescence lifespan, a polymeric compound including a structural unit represented by Chemical Formula 1, or a structural unit represented by Chemical Formula 1 and a structural unit represented by Chemical Formula 2, and an electroluminescent device material or electroluminescent device including the same are provided: In Chemical Formula 1 and Chemical Formula 2, R11 to R14 are not the same as R41 to R44.

Abstract: A quantum dot device and an electronic device. The quantum dot device includes a first electrode and an opposite facing second electrode, a light emitting layer disposed between the first electrode and the second electrode and including quantum dots, a first electron auxiliary layer proximate to the light emitting layer and disposed between the second electrode and the light emitting layer and including a first electron auxiliary material, a second electron auxiliary layer proximate to the second electrode and disposed between the second electrode and the light emitting layer and including a second electron auxiliary material, and an insertion layer disposed between the first electron auxiliary layer and the second electron auxiliary layer and including an inorganic material, wherein a HOMO energy level of the inorganic material is deeper than a HOMO energy level of the first electron auxiliary material, and a HOMO energy level of the second electron auxiliary material, respectively.

Abstract: An inkjet printhead includes a head body in which a first fine channel that is connected to an ink inlet and thus guides an inflow of ink, a second fine channel that is disposed below the first fine channel, communicated with the first fine channel through a connection via hole, and guides an outflow of the ink by being connected to an ink outlet, and a nozzle that is opened downward from the second fine channel are defined, and a micro heater that is disposed closer to the connection via hole in an upper portion of the first fine channel than to an end of the first fine channel where the first fine channel is connected to the ink inlet or an end of the second fine channel where the second fine channel is connected to the ink outlet.

Abstract: A quantum dot, including a core including a first semiconductor material that includes indium; and a shell including a second semiconductor material, and disposed on the core, wherein the first semiconductor material and the second semiconductor material are different, wherein the shell has at least two branch portions and a valley portion connecting the at least two branch portions, at least one of the at least two branch portions comprises Zn, Se, and S, and a content of sulfur in the at least one branch portion increases in a direction away from the core.

Abstract: An electroluminescent device including an anode; a cathode; a light emitting layer disposed between the anode and the cathode; and an electron transport layer disposed between the light emitting layer and the cathode, wherein the light emitting layer includes a plurality of semiconductor nanoparticles, the electron transport layer includes zinc oxide nanoparticles including a Group IIA metal and an acid salt of an alkali metal that has an oxycarbonyl moiety, and the zinc oxide nanoparticles have an average size of less than or equal to about 20 nanometers (nm).

Abstract: A semiconductor nanocrystal particle including a transition metal chalcogenide represented by Chemical Formula 1, the semiconductor nanocrystal particle having a size of less than or equal to about 100 nanometers, and a method of producing the same: M1M2Cha3??Chemical Formula 1 wherein M1 is Ca, Sr, Ba, or a combination thereof, M2 is Ti, Zr, Hf, or a combination thereof, and Cha is S, Se, Te, or a combination thereof.

Abstract: A cadmium free quantum dot includes zinc, tellurium, and selenium, and lithium. A full width at half maximum of a maximum luminescent peak of the cadmium free quantum dot is less than or equal to about 50 nanometers and the cadmium free quantum dot has a quantum efficiency of greater than 1%.

Abstract: A quantum dot including a semiconductor nanocrystal core and a semiconductor nanocrystal shell disposed on the core and does not include cadmium, wherein the core includes a Group III-V compound, the quantum dot has a maximum photoluminescence peak in a green light wavelength region, a full width at half maximum (FWHM) of the maximum photoluminescence peak is less than about 50 nanometers (nm), and a difference between a wavelength of the maximum photoluminescence peak and a first absorption peak wavelength of the quantum dot is less than or equal to about 25 nanometers, and a production method thereof.

Abstract: A quantum dot including a core that includes a first semiconductor nanocrystal including zinc and selenium, and optionally sulfur and/or tellurium, and a shell that includes a second semiconductor nanocrystal including zinc, and at least one of sulfur or selenium is disclosed. The quantum dot has an average particle diameter of greater than or equal to about 13 nm, an emission peak wavelength in a range of about 440 nm to about 470 nm, and a full width at half maximum (FWHM) of an emission wavelength of less than about 25 nm. A method for preparing the quantum dot, a quantum dot-polymer composite including the quantum dot, and an electronic device including the quantum dot is also disclosed.

Abstract: A quantum dot according to an embodiment includes a core including a first semiconductor nanocrystal including zinc, selenium, and tellurium and a semiconductor nanocrystal shell on the core, the semiconductor nanocrystal shell including a zinc chalcogenide, wherein the quantum dot does not include cadmium, the zinc chalcogenide includes zinc and selenium, the quantum dot further includes gallium and a primary amine having 5 or more carbon atoms, and the quantum dot is configured to emit light having a maximum emission peak in a range of greater than about 450 nanometers (nm) and less than or equal to about 480 nm by excitation light. A method of producing the quantum dot and an electronic device including the same are also disclosed.

Abstract: An electroluminescent device including a first electrode and a second electrode spaced apart from each other (e.g., each electrode having a surface opposite the other), and a light emitting layer disposed between the first electrode and the second electrode, and an electron transport layer disposed between the light emitting layer and the second electrode, wherein the light emitting layer includes semiconductor nanoparticles, wherein the electron transport layer includes a plurality of zinc oxide nanoparticles, and wherein the electron transport layer further includes an alkali metal and a halogen.

Abstract: A cadmium free quantum dot not including cadmium and including: a semiconductor nanocrystal core comprising indium and phosphorous, a first semiconductor nanocrystal shell disposed on the semiconductor nanocrystal core and comprising zinc and selenium, and a second semiconductor nanocrystal shell disposed on the first semiconductor nanocrystal shell and comprising zinc and sulfur, a composition and composite including the same, and an electronic device.

Abstract: An electroluminescent device includes a first electrode and a second electrode spaced apart from each other, and a light emitting layer including semiconductor nanoparticles. The semiconductor nanoparticles do not contain cadmium, the semiconductor nanoparticles include zinc, selenium, tellurium, and sulfur, the semiconductor nanoparticles have a core-shell structure including a core including a first semiconductor nanocrystal and a shell disposed on the core, the first semiconductor nanocrystals include a first zinc chalcogenide containing sulfur, in the semiconductor nanoparticles, a mole ratio of sulfur to tellurium is greater than or equal to about 0.5:1 and less than or equal to about 110:1, and the semiconductor nanoparticles are configured to emit light having a maximum emission peak wavelength of greater than or equal to about 440 nanometers (nm) and less than or equal to about 580 nm, and the semiconductor nanoparticles have a quantum yield of greater than or equal to about 40%.

Abstract: A semiconductor nanocrystal particle including: a core including a first semiconductor material; and a shell disposed on the core, wherein the shell includes a second semiconductor material, wherein the shell is free of cadmium, wherein the shell has at least two branches and at least one valley portion connecting the at least two branches, and wherein the first semiconductor material is different from the second semiconductor material.

Abstract: A quantum dot device including a first electrode and a second electrode each having a surface opposite the other, a quantum dot layer disposed between the first electrode and the second electrode, and an electron auxiliary layer disposed between the quantum dot layer and the second electrode, wherein the electron auxiliary layer includes inorganic nanoparticles including an alkaline-earth metal, and an alkali metal, an alkali metal compound, or a combination thereof, and an electronic device including the quantum dot device.

Abstract: A semiconductor nanoparticle, a production method thereof, and an electroluminescent device including the same. The production method includes: combining a magnesium precursor and an additive with a chalcogen precursor in a reaction medium including an organic solvent and an organic ligand; heating the reaction medium to a reaction temperature; and reacting the magnesium precursor and the chalcogen precursor in the presence of the additive to form a magnesium chalcogenide, wherein the semiconductor nanoparticle comprises the magnesium chalcogenide, wherein the magnesium chalcogenide comprises magnesium; and selenium, sulfur, or a combination thereof, and wherein the additive includes a hydride compound including an alkali metal, calcium, barium, aluminum, or a combination thereof.

Abstract: A light emitting device including a first electrode and a second electrode spaced from each other, and, a light emitting film between the first electrode and the second electrode, wherein the light emitting film has a first surface facing the second electrode and a second surface opposite thereto, the light emitting film includes a quantum dot layer including a plurality of quantum dots and a matrix including a metal chalcogenide, the plurality of quantum dots includes selenium, the matrix covers at least a portion of the quantum dot layer, the metal chalcogenide comprises zinc and sulfur, and in an X-ray photoelectron spectroscopic analysis of the first surface of the light emitting film, a mole ratio of zinc with respect to selenium is greater than or equal to about 2:1 and a mole ratio of sulfur with respect to selenium is greater than or equal to about 1.1:1.

Abstract: A quantum dot including a core comprising a first semiconductor nanocrystal including a zinc chalcogenide and a semiconductor nanocrystal shell disposed on the surface of the core and comprising zinc, selenium, and sulfur. The quantum dot does not comprise cadmium, emits blue light, and may exhibit a digital diffraction pattern obtained by a Fast Fourier Transform of a transmission electron microscopic image including a (100) facet of a zinc blende structure. In an X-ray diffraction spectrum of the quantum dot, a ratio of a defect peak area with respect to a peak area of a zinc blende crystal structure is less than about 0.8:1. A method of producing the quantum dot, and an electroluminescent device including the quantum dot are also disclosed.