Composite nanoparticle compositions and associated nanoparticle assemblies exhibit enhancements to one or more thermoelectric properties including increases in electrical conductivity and/or Seebeck coefficient and/or decreases in thermal conductivity. A composite nanoparticle composition comprises a semiconductor nanoparticle including a front face and a back face and sidewalls extending between the front and back faces. Metallic nanoparticles are bonded to at least one of the sidewalls establishing a metal-semiconductor junction.

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.

A process for synthesizing a material, includes: (a) providing a plurality of powders including at least one lithiated powder including lithium, at least one TM powder including, for more than 95.0% of its mass, a transition metal chosen from titanium; cobalt, manganese, nickel, niobium, tin, iron and mixtures thereof, and at least one chalcogen powder including, for more than 95.0% of its mass, a chalcogen element chosen from sulfur, selenium, tellurium and mixtures thereof, (b) preparing a particulate mixture by mixing all the powders of the plurality or by mixing one of the powders of the plurality with a milled material obtained by; milling a particulate assembly formed by mixing at least two of the other powders of the plurality, and (c) milling the particulate fixture to form the material.

A process for preparing stacks of metal chalcogenide flakes includes: (a) reacting together a source of the metal atom of the target metal chalcogenide with a source of the chalcogenide atom of the target metal chalcogenide, in the presence of a spacer, so as to produce flakes of the metal chalcogenide; (b) depositing metal chalcogenide flakes obtained using step (a) onto a substrate to form a stack of assembled metal chalcogenide flakes, wherein the spacer contains an alkyl chain linked to a functional group able to bond to the metal chalcogenide surface, said alkyl chain having a length of less than 18 carbon atoms, preferably between 6 and 14 carbon atoms.

The invention relates to methods for preparing 3-element semiconductor nanocrystals of the formula WYxZ(1-x), wherein W is a Group II element, Y and Z are different Group VI elements, and 0<X<1, comprising dissolving a Group II element, a first Group VI element, and a second Group VI element in a one or more solvents. The Group II, VI and VI elements are combined to provide a II:VI:VI SCN precursor solution, which is heated to a temperature sufficient to produce semiconductor nanocrystals of the formula WYxZ(1-x). The solvent used to dissolve the Group II element comprises octadecene and a fatty acid. The solvent used to dissolve the Group VI elements comprises octadecene. The invention also includes semiconductor nanocrystals prepared according to the disclosed methods, as well as methods of using the semiconductor nanocrystals.

Preparation of two-dimensional indium selenide, other two-dimensional materials and related compositions via surfactant-free deoxygenated co-solvent systems.

The present application discloses a thermoelectric material, which contains CsAg.sub.5Te.sub.3 crystal material. At 700K, the thermoelectric material has an optimum dimensionless figure-of-merit Z1 as high as 1.6 and a high stability, and the thermoelectric material can be recycled. The present application also discloses a method for preparing the CsAg.sub.5Te.sub.3 crystal material. The CsAg.sub.5Te.sub.3 crystal material is one-step synthesized by a high-temperature solid-state method, using a raw material containing Cs, Ag and Te, so that the high-purity product is obtained while the synthesis time is greatly shortened.

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.

Provided are nanoparticles passivated with a cationic metal-chalcogenide complex (MCC) and a method of preparing the same. A passivated nanoparticle includes: a core nanoparticle; and a cationic metal-chalcogenide compound (MCC) fixed on a surface of the core nanoparticle.

The present disclosure generally relates to compositions comprising substrate-free 2D crystalline nanomaterials of binary compounds of formula (M).sub.x(Te).sub.y, and the method of making and using the substrate-free crystalline 2D crystalline nanomaterial.