The present invention is directed to methods of preparing metal sulfide, metal selenide, or metal sulfide/selenide nanoparticles and the products derived therefrom. In various embodiments, the nanoparticles are derived from the reaction between precursor metal salts and certain sulfur- and/or selenium-containing precursors each independently having a structure of Formula (I), (II), or (III), or an isomer, salt, or tautomer thereof, where Q.sup.1,Q.sup.2,Q.sup.3,R.sup.1,R.sup.2,R.sup.3,R.sup.5, and X are defined within the specification.

The present application discloses a method for preparing metal oxide nanoparticles, including the following steps: providing an organic reagent with a molecular formula of X—(SO.sub.2)—Y and a metal oxide nanoparticle sample, in which the metal oxide nanoparticle sample is an aqueous metal oxide nanoparticle; in X—(SO.sub.2)—Y, X contains polar functional groups; mixing the organic reagent and the metal oxide nanoparticle sample in a liquid medium and adding an alkaline reagent to a mixed solution of the organic reagent and the metal oxide nanoparticle sample to prepare the metal oxide nanoparticles. The method provided in the present application can reduce the surface defect state of metal oxide nanoparticles, thereby improving the stability of metal oxide nanoparticles.

Methods of synthesizing transition metal dichalcogenide nanoparticles include forming a metal-amine complex, combining the metal-amine complex with a chalcogen source in at least one solvent to form a solution, heating the solution to a first temperature for a first period of time, and heating the solution to a second temperature that is higher than the first temperature for a second period of time.

Methods of synthesizing transition metal dichalcogenide nanoparticles include forming a metal-amine complex, combining the metal-amine complex with a chalcogen source in at least one solvent to form a solution, heating the solution to a first temperature for a first period of time, and heating the solution to a second temperature that is higher than the first temperature for a second period of time.

A method of synthesis of two-dimensional (2D) nanoparticles comprises combining a first nanoparticle precursor and a second nanoparticle precursor in one or more solvents to form a solution, followed by heating the solution to a first temperature for a first time period, then subsequently heating the solution to a second temperature for a second time period, wherein the second temperature is higher than the first temperature, to effect the conversion of the nanoparticle precursors into 2D nanoparticles. In one embodiment, the first nanoparticle precursor is a metal-amine complex and the second nanoparticle precursor is a slow-releasing chalcogen source.

According to one embodiment, a product is a mixture including a solvent and generally spherical colloidal nanoparticles, the colloidal nanoparticles each having a core and a shell surrounding the core, and an electrode. In addition, the mixture is characterized as having a transparency to light in a predetermined wavelength range, where the transparency increases as a voltage of the electrode increases.

A polymer material comprises one or more different doping elements. The or at least one of the different doping elements at least partially absorbs an electromagnetic radiation emitted by a human or animal body and at least partially emits an electromagnetic radiation in an infrared range, preferably in an infrared C range. A textile material comprises the polymer material according to the invention. The invention further relates to medical and non-medical uses of the polymer material according to the invention and to a manufacturing method of the polymer material according to the invention.

According to one embodiment, a product is a mixture including a solvent and generally spherical colloidal nanoparticles, the colloidal nanoparticles each having a core and a shell surrounding the core, and an electrode. In addition, the mixture is characterized as having a transparency to light in a predetermined wavelength range, where the transparency increases as a voltage of the electrode increases.

A quantum dot includes: a core including at least one first positive ion precursor and at least one negative ion precursor; a shell including at least one second positive ion precursor and at least one negative ion precursor and wrapping the core; and a ligand formed on a surface of the shell, wherein the first positive ion precursor is an n-period element and the second positive ion precursor is an (n-1)-period element, where n is an integer of 3 to 6.

A method of synthesis of two-dimensional (2D) nanoparticles comprises combining a first nanoparticle precursor and a second nanoparticle precursor in one or more solvents to form a solution, followed by heating the solution to a first temperature for a first time period, then subsequently heating the solution to a second temperature for a second time period, wherein the second temperature is higher than the first temperature, to effect the conversion of the nanoparticle precursors into 2D nanoparticles. In one embodiment, the first nanoparticle precursor is a metal-amine complex and the second nanoparticle precursor is a slow-releasing chalcogen source.