A fluorescent nanocomposite which includes a thallium doped gadolinium chalcogenide having formula Tl.sub.xGd.sub.1-xY, wherein x is 0.01 to 0.1, and Y is selected from the group consisting of S, Se, or Te, and a benzothiazolium salt bound to a surface of the thallium doped gadolinium chalcogenide. A method of detecting antimony ions in a fluid sample whereby the fluid sample is contacted with the fluorescent nanocomposite to form a mixture, and a fluorescence emission profile of the mixture is measured to determine a presence or absence of antimony ions in the fluid sample, wherein a reduction in intensity of a fluorescence emissions peak associated with the fluorescent nanocomposite indicates the presence of antimony ions in the fluid sample.

A composition can include a copper containing nanocrystal.

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.

Provided are methods for obtaining n-type doped metal chalcogenide quantum dot solid-state films. In some embodiments, the methods include forming an metal chalcogenide quantum dot solid-state film, carrying out a n-doping process on the metal chalcogenide quantum dots of the metal chalcogenide quantum dot solid-state film so that they exhibit intraband absorption, wherein the process includes partially substituting chalcogen atoms by halogen atoms in the metal chalcogenide quantum dots and providing a substance on the plurality of metal chalcogenide quantum dots, to avoid oxygen p-doping of the metal chalcogenide quantum dots. Also provided are optoelectronic devices, which in some embodiments can include an n-type doped metal chalcogenide quantum dot solid-state film (A) obtained by a method as disclosed herein and first (E1) and second (E2) electrodes in physical contact with two respective distanced regions of the film (A).

A fluorescent nanocomposite which includes a thallium doped gadolinium chalcogenide having formula Tl.sub.xGd.sub.1-xY, wherein x is 0.01 to 0.1, and Y is selected from the group consisting of S, Se, or Te, and a benzothiazolium salt bound to a surface of the thallium doped gadolinium chalcogenide. A method of detecting antimony ions in a fluid sample whereby the fluid sample is contacted with the fluorescent nanocomposite to form a mixture, and a fluorescence emission profile of the mixture is measured to determine a presence or absence of antimony ions in the fluid sample, wherein a reduction in intensity of a fluorescence emissions peak associated with the fluorescent nanocomposite indicates the presence of antimony ions in the fluid sample.

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%.

A nanocomposite includes: a matrix phase; and a functional area disposed in the matrix phase. The functional area contains monocrystal fine particles.

Nanophosphors are provided comprising a nanoparticle core having an attached shell of smaller silicon nanoparticles attached via hydrogen bonding. Example methods for forming a nanophosphor comprise providing a silicon nanoparticle (SiNp) colloid including Si nanoparticles, and transferring the colloid to a solid state comprising silica and/or phosphor particles. Drying is allowed such that the Si nanoparticles form a coating on the particles with hydrogen bonds.

Quantum dots including semiconductor nanocrystals, methods of producing the same, and quantum dot solutions and electronic devices including the same. The quantum dots do not include cadmium, lead, or a combination thereof. The quantum dots include an organic ligand and a halogen on the surfaces, and the quantum dots are dispersible in an organic solvent to form organic solutions.

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.