A quantum dot, a quantum dot-polymer composite, and an electronic device including the same The quantum dot includes a core including a first semiconductor nanocrystal; a first shell including a second semiconductor nanocrystal including a Group III-VI compound on the core; and a second shell including a third semiconductor nanocrystal having a composition different from that of the second semiconductor nanocrystal on the first shell; wherein one of the first semiconductor nanocrystal and the third semiconductor nanocrystal includes a Group III-V compound.

To provide Cd-free chalcopyrite-based quantum dots with a narrow fluorescence FWHM and a high fluorescence quantum yield. The quantum dots of the present invention contain AgIn.sub.xGa.sub.1-xS.sub.ySe.sub.1-y or ZnAgIn.sub.xGa.sub.1-xS.sub.ySe.sub.1-y (where 0≤x<1 and 0≤y≤1) and exhibit fluorescence properties including a fluorescence FWHM of less than or equal to 45 nm and a fluorescence quantum yield of greater than or equal to 35% in the green wavelength range to the red wavelength range.

A method for manufacturing a sputtering target with which an oxide semiconductor film with a small amount of defects can be formed is provided. Alternatively, an oxide semiconductor film with a small amount of defects is formed. A method for manufacturing a sputtering target is provided, which includes the steps of: forming a polycrystalline In-M-Zn oxide (M represents a metal chosen among aluminum, titanium, gallium, yttrium, zirconium, lanthanum, cesium, neodymium, and hafnium) powder by mixing, sintering, and grinding indium oxide, an oxide of the metal, and zinc oxide; forming a mixture by mixing the polycrystalline In-M-Zn oxide powder and a zinc oxide powder; forming a compact by compacting the mixture; and sintering the compact.

A method of producing semiconductor nanoparticles is provided. The method includes heating primary semiconductor nanoparticles and a salt of an element M.sup.1 in a solvent at a temperature set in a range of 100° C. to 300° C. The primary semiconductor nanoparticles contain the element M.sup.1, an element M.sup.2, optionally an element M.sup.3, and an element Z, and have an average particle size of 50 nm or less. The element M.sup.1 is at least one element selected from the group consisting of Ag, Cu, and Au. The element M.sup.2 is at least one element selected from the group consisting of Al, Ga, In, and Tl. The element M.sup.3 is at least one element selected from the group consisting of Zn and Cd. The element Z is at least one element selected from the group consisting of S, Se, and Te.

The nanoparticle assembly includes nanoparticles having an average primary particle size of 60 nm or less, and the nanoparticle assembly has a diameter of more than 500 nm and 5 μm or less.

The nanoparticle assembly includes nanoparticles having an average primary particle size of 60 nm or less, and the nanoparticle assembly has a diameter of more than 500 nm and 5 μm or less.

The present invention relates to a composite having the ability to stably and reliably detect a target gas even in a moist environment. The composite of the present invention includes: a nanostructure of an oxide semiconductor selected from the group consisting of SnO.sub.2, ZnO, WO.sub.3, NiO, and In.sub.2O.sub.3; and a CeO.sub.2 additive loaded on the nanostructure. The oxide semiconductor nanostructure is uniformly loaded with CeO.sub.2. The composite of the present invention can rapidly detect an analyte gas with high gas response irrespective of the presence and concentration of moisture. The present invention also relates to methods for preparing the composite, a gas sensor including the composite as a material for a gas sensing layer, and a method for fabricating the gas sensor.

The present invention relates to a composite having the ability to stably and reliably detect a target gas even in a moist environment. The composite of the present invention includes: a nanostructure of an oxide semiconductor selected from the group consisting of SnO.sub.2, ZnO, WO.sub.3, NiO, and In.sub.2O.sub.3; and a CeO.sub.2 additive loaded on the nanostructure. The oxide semiconductor nanostructure is uniformly loaded with CeO.sub.2. The composite of the present invention can rapidly detect an analyte gas with high gas response irrespective of the presence and concentration of moisture. The present invention also relates to methods for preparing the composite, a gas sensor including the composite as a material for a gas sensing layer, and a method for fabricating the gas sensor.

A crystalline structure compound A is represented by a composition formula (2) and has having diffraction peaks respectively in below-defined ranges (A) to (K) of an incidence angle observed by X-ray diffraction measurement.

(In.sub.xGa.sub.yAl.sub.z).sub.2O.sub.3  (2)

In the formula (2), 0.47≤x≤0.53, 0.17≤y≤0.43, 0.07≤z≤0.33, and x+y+z=1.

31° to 34° (A), 36° to 39° (B), 30° to 32° (C), 51° to 53° (D), 53° to 56° (E), 62° to 66° (F), 9° to 11° (G), 19° to 21° (H), 42° to 45° (I), 8° to 10° (J), and 17° to 19° (K).

A crystalline structure compound A is represented by a composition formula (2) and has having diffraction peaks respectively in below-defined ranges (A) to (K) of an incidence angle observed by X-ray diffraction measurement.

(In.sub.xGa.sub.yAl.sub.z).sub.2O.sub.3  (2)

In the formula (2), 0.47≤x≤0.53, 0.17≤y≤0.43, 0.07≤z≤0.33, and x+y+z=1.

31° to 34° (A), 36° to 39° (B), 30° to 32° (C), 51° to 53° (D), 53° to 56° (E), 62° to 66° (F), 9° to 11° (G), 19° to 21° (H), 42° to 45° (I), 8° to 10° (J), and 17° to 19° (K).