A method is provided for producing an article which is transparent to near-wave IR, mid-wave and Long-wave multi-spectral and IR wavelength in the region of 0.4 μm to 16 μm. The method includes the steps of (a) Producing ultra-fine powder of CaLa.sub.2S.sub.4 via SPLTS process, (b) followed by pretreatment of the ultra-fine powder under inert and reducing gas conditions including H.sub.2 or Argon or N.sub.2 or H.sub.2/H.sub.2S, H.sub.2S, and mixtures there of (c) followed by sieving the powder in 140 mesh screen and cold pressing the powder at 7000 psi for 7 min. into a disk shaped green body (d) then Cold-Isostatic Pressing (CIP) at 40,000 psi for 5 min in a rubber mold (e) finally sintered article of CaLa.sub.2S.sub.4 disk of 25.4 mm diameter with ultra-high density containing cubic phase of CaLa.sub.2S.sub.4 to yield IR transmission of a peak value of 57% within the IR wavelength range of 2 μm to 16 μm, either by using microwave sintering followed by hot isostatic press or spark plasma sintering followed by hot isostatic press or vacuum sintering at (3×10.sup.−6 torr) followed by hot isostatic press or hot press sintering followed by hot isostatic press and finally followed by mirror polished IR article, is obtained.

Composite nanoparticle compositions and associated nanoparticle assemblies are described herein which, in some embodiments, exhibit enhancements to one or more thermoelectric properties including increases in electrical conductivity and/or Seebeck coefficient and/or decreases in thermal conductivity. In one aspect, 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.

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

The present disclosure is a photoelectric conversion element including: a photoelectric conversion layer 5 including a first quantum dot 4a and a second quantum dot 4b, a ratio X of the number of heavy metal atoms to the number of oxygen group atoms is less than 2 on a surface of the nanoparticle of the first quantum dot 4a, the ratio X is greater than or equal to 2 on a surface of the nanoparticle of the second quantum dot 4b, and Equation (1) is satisfied:
0.3<N  (1),
where N denotes a ratio of the number of second quantum dots to the number of first quantum dots.

A quantum dot device and an electronic device including the device are provided. The quantum dot device includes a first electrode and a second electrode, a quantum dot layer disposed between the first electrode and the second electrode, and a hole auxiliary layer disposed between the quantum dot layer and the first electrode, wherein the hole auxiliary layer includes nickel oxide and a self-assembled monolayer disposed between the hole auxiliary layer and the quantum dot layer, the self-assembled monolayer including an organic compound represented by Chemical Formula 1.

A method for obtaining at least one particle, including: (a) preparing solution A including at least one precursor of at least one of Si, B, P, Ge, As, Al, Fe, Ti, Zr, Ni, Zn, Ca, Na, Ba, K, Mg, Pb, Ag, V, Te, Mn, Ir, Sc, Nb, Sn, Ce, Be, Ta, S, Se, N, F, and Cl; (b) preparing aqueous solution B; (c) forming droplets of solution A; (d) forming droplets of solution B; (e) mixing droplets; (f) dispersing mixed droplets in a gas flow; (g) heating dispersed droplets to obtain the at least one particle; (h) cooling the at least one particle; and (i) separating and collecting the at least one particle. The aqueous solution is acidic, neutral, or basic. In step (a) and/or step (b) at least one colloidal suspension of a plurality of nanoparticles is mixed with the solution. Also, a device for implementing the method.

A composite material is provided. The composite material includes carbon layers and metal compound layers alternately and repeatedly stacked. Each of the metal compound layers includes molybdenum and selenium. When the composite material is used as a positive active material for a lithium selenium secondary battery, selenium is separated from the metal compound layer through a preliminary charge/discharge process. In addition, the composite material may be used as negative active materials of a lithium ion battery and a lithium ion capacitor. Furthermore, the composite material may be used as an active material of a positive electrode of the lithium selenium secondary battery.

The invention relates to Chevrel-phase materials and methods of preparing these materials utilizing a precursor approach. The Chevrel-phase materials are useful in assembling electrodes, e.g., cathodes, for use in electrochemical cells, such as rechargeable batteries. The Chevrel-phase materials have a general formula of Mo.sub.6Z.sub.8 (Z=sulfur) or Mo.sub.6Z.sup.1.sub.8-yZ.sup.2.sub.y (Z.sup.1=sulfur; Z.sup.2=selenium), and partially cuprated Cu.sub.1Mo.sub.6S.sub.8 as well as partially de-cuprated Cu.sub.1-xMg.sub.xMo.sub.6S.sub.8 and the precursors have a general formula of M.sub.xMo.sub.6Z.sub.8 or M.sub.xMo.sub.6Z.sup.1.sub.8-yZ.sup.2.sub.y, M=Cu. The cathode containing the Chevrel-phase material in accordance with the invention can be combined with a magnesium-containing anode and an electrolyte.

Provided is a luminescent material having excellent durability. The luminescent material contains second semiconductor nanoparticles that contain first semiconductor nanoparticles and a deposit arranged on surfaces of the first semiconductor nanoparticles, and that emit light when irradiated with light; and a metal compound in which the second semiconductor nanoparticles are embedded. The first semiconductor nanoparticles contain M.sup.1, M.sup.2, and Z. M.sup.1 is at least one selected from the group consisting of Ag, Cu, Au and alkali metals, and contains at least Ag. M.sup.2 is at least one selected from the group consisting of Al, Ga, In and Tl, and contains at least one of In and Ga. Z contains at least one selected from the group consisting of S, Se, and Te. The deposit is substantially composed of at least one selected from the group consisting of Al, Ga, In, Tl and alkali metals, and at least one selected from the group consisting of S, O, Se, and Te. The metal compound contains at least one of Zn and Ga, and at least one of S and O.

Provided are novel transition metal dichalcogenides having a platelet structure and comprising a 2H phase region and/or a 3R phase region. The platelets exhibit a narrow size distribution and comparatively high surface area and edge area, which characteristics render the platelets especially suitable for catalysis applications, as well as use in electronic devices. Also provided are methods of synthesizing the disclosed transition metal dichalcogenide platelets.