There are provided particles in which a dispersant can be easily removed from semiconductor nanocrystals, an ink with good storage stability, and a light-emitting device with a long emission lifetime. Particles according to the present invention contain light-emitting semiconductor nanocrystals and a dispersant supported on the semiconductor nanocrystals and having a boiling point of 300 C. or less at atmospheric pressure. An ink according to the present invention contains particles according to the present invention and a dispersion medium having a boiling point equal to or higher than the boiling point of the dispersant at atmospheric pressure and containing a polar compound with a polar group.

The silyl phosphine compound of the present invention is represented by the formula (1) and has an arsenic content of not more than 1 ppm. The process for producing a silyl phosphine compound of the present invention is a process comprising mixing a basic compound, a silylating agent and phosphine to obtain a solution containing a silyl phosphine compound, removing a solvent from the solution to obtain a concentrated solution of a silyl phosphine compound, and distilling the concentrated solution, wherein an arsenic content in the phosphine is adjusted to not more than 1 ppm by volume in terms of arsine. The process for producing InP quantum dots of the present invention uses, as a phosphorus source, a silyl phosphine compound represented by the formula (1) and having an arsenic content of not more than 1 ppm by mass.

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(For definition of R, see the specification.)

Organically capped quantum dots are made by functionalizing the surfaces of QDs of various architectures with a combination of 6-mercaptohexanol (MCH) and 2-[2-(2-methoxyethoxy)-ethoxy]-acetic acid (MEEAA). Such MCH/MEEAA-capped QDs exhibit improved compatibility with solvents used in the fabrication of QD-containing films of light emitting devices, such as liquid crystal displays.

Organically capped quantum dots are made by functionalizing the surfaces of QDs of various architectures with a combination of 6-mercaptohexanol (MCH) and 2-[2-(2-methoxyethoxy)-ethoxy]-acetic acid (MEEAA). Such MCH/MEEAA-capped QDs exhibit improved compatibility with solvents used in the fabrication of QD-containing films of light emitting devices, such as liquid crystal displays.

The present invention discloses a method for carrying out phosphide in-situ injection synthesis by carrier gas, relating to a synthetic method of semiconductor crystal: step A, shielding inert gas is introduced into a furnace body through a carrier gas intake conduit; step B, a crucible is heated in the furnace body to melt a pre-synthesized raw material in the crucible; step C, the heated shielding inert gas is introduced into the furnace body through the carrier gas intake conduit; step D, a phosphorus source furnace loaded with red phosphorus is moved downwards until an injection conduit of the phosphorus source furnace is submerged in the melt; step E, the red phosphorus is heated by the phosphorus source furnace to produce phosphorus gas, and the phosphorus gas is mixed with the shielding inert gas and then injected into the melt through the injection conduit, and the phosphorus gas reacts with the melt to produce phosphide; and step F, each device is turned off after the synthesis is finished. In the present invention in the synthesis process, the shielding inert gas is introduced through the carrier gas intake conduit to enable the phosphorus gas to be stably injected into the melt, so that the melt is prevented from being sucked back into the phosphorus source furnace after the volatile element gas is completely absorbed.

The present invention discloses a method for carrying out phosphide in-situ injection synthesis by carrier gas, relating to a synthetic method of semiconductor crystal: step A, shielding inert gas is introduced into a furnace body through a carrier gas intake conduit; step B, a crucible is heated in the furnace body to melt a pre-synthesized raw material in the crucible; step C, the heated shielding inert gas is introduced into the furnace body through the carrier gas intake conduit; step D, a phosphorus source furnace loaded with red phosphorus is moved downwards until an injection conduit of the phosphorus source furnace is submerged in the melt; step E, the red phosphorus is heated by the phosphorus source furnace to produce phosphorus gas, and the phosphorus gas is mixed with the shielding inert gas and then injected into the melt through the injection conduit, and the phosphorus gas reacts with the melt to produce phosphide; and step F, each device is turned off after the synthesis is finished. In the present invention in the synthesis process, the shielding inert gas is introduced through the carrier gas intake conduit to enable the phosphorus gas to be stably injected into the melt, so that the melt is prevented from being sucked back into the phosphorus source furnace after the volatile element gas is completely absorbed.

An object of the present invention is to provide a semiconductor nanoparticle having high emission efficiency and excellent durability; a method of producing the same; and a dispersion liquid and a film obtained by using a semiconductor nanoparticle. The semiconductor nanoparticle of the present invention is a semiconductor nanoparticle in which oxygen, zinc, and sulfur are detected by X-ray photoelectron spectroscopy analysis and a peak (I.sub.CH3) which is derived from a hydrocarbon group and present in a range of 2800 cm.sup.1 to 3000 cm.sup.1 and a peak (I.sub.COO) which is derived from COO.sup. and present in a range of 1400 cm.sup.1 to 1600 cm.sup.1 are detected by Fourier transform infrared spectroscopy analysis.

A method for producing a Group III-V semiconductor nanoparticle by flow reaction, including: introducing a solution of compound containing Group III element into a first flow channel, introducing a solution of compound containing Group V element into a second flow channel, and combining the solutions to produce nanoparticles, in which the combining portion is constituted by a multi-layered tubular mixer, one of the solutions is allowed to flow through a flow channel in the smallest tube of the mixer, and the other of the solutions is allowed to flow through a flow channel adjacent to the flow channel in the smallest tube, and a value of a ratio of linear velocity of the solution flowing in the flow channel adjacent to the flow channel in the smallest tube to linear velocity of the solution flowing in the flow channel in the smallest tube is a specific value.

Provided are semiconductor particles including a Group 12-16 semiconductor including a Group 12 element and a Group 16 element, a Group 13-15 semiconductor including a Group 13 element and a Group 15 element, or a Group 14 semiconductor including a Group 14 element, the semiconductor particles having a plasma frequency of 1.710.sup.14 rad/s to 4.710.sup.14 rad/s and a maximum length of 1 nm to 2,000 nm; and a dispersion, a film, an optical filter, a building member, or a radiant cooling device, in all of which the semiconductor particles are used.

Methods of synthesizing colloidal ternary Group III-V nanocrystals are provided. Also provided are the colloidal ternary Group III-V nanocrystals made using the methods. In the methods, molten inorganic salts are used as high temperature solvents to carry out cation exchange reactions that convert binary nanocrystals into ternary nanocrystals.