Proposed are a layered Group III-V compound having ferroelectric properties, a Group III-V compound nanosheet that may be prepared using the same, and an electrical device including the materials. Proposed is a layered compound represented by [Formula 1] M.sub.x−mA.sub.yB.sub.z (M is at least one of Group I or Group II elements, A is at least one of Group III elements, B is at least one of Group V elements, x, y, and z are positive numbers which are determined according to stoichiometric ratios to ensure charge balance when m is 0, and 0<m<x), and having ferroelectric-like properties.

Proposed are a layered compound having indium and phosphide, a nanosheet that may be prepared using the same, and an electrical device including the materials. Proposed is a layered compound represented by K.sub.1-xIn.sub.yP.sub.z (0≤x≤1.0, 0.75≤y≤1.25, 1.25≤z≤1.75).

A method for producing a sulfide solid electrolyte includes: preparing a uniform solution that includes at least elemental lithium (Li), elemental tin (Sn), elemental phosphorus (P), and elemental sulfur (S) in an organic solvent; removing the organic solvent from the uniform solution to obtain a precursor; and heat-treating the precursor to obtain a sulfide solid electrolyte.

Quantum dot semiconductor nanoparticle compositions that incorporate ions such as zinc, aluminum, calcium, or magnesium into the quantum dot core have been found to be more stable to Ostwald ripening. A core-shell quantum dot may have a core of a semiconductor material that includes indium, magnesium, and phosphorus ions. Ions such as zinc, calcium, and/or aluminum may be included in addition to, or in place of, magnesium. The core may further include other ions, such as selenium, and/or sulfur. The core may be coated with one (or more) shells of semiconductor material. Example shell semiconductor materials include semiconductors containing zinc, sulfur, selenium, iron and/or oxygen ions.

Provided are core/shell type semiconductor nanoparticles including: a core including In and P; and a shell having one or more layers. The semiconductor nanoparticles further include at least Zn, Se, and at least one halogen. In the semiconductor nanoparticles, molar ratios of P, Zn, Se, and halogen each relative to In in terms of atoms are P: 0.20˜0.95, Zn: 11.00˜50.00, Se: 7.00˜25.00, and halogen: 0.80˜15.00. According to the present invention, core/shell type semiconductor nanoparticles that include the core including In and P and the shell including Zn and Se as main components, and have high quantum yield, a small full width at half maximum, and small Stokes shift can be provided.

Proposed are a layered Group III-V compound having ferroelectric properties, a Group III-V compound nanosheet that may be prepared using the same, and an electrical device including the materials. Proposed is a layered compound represented by [Formula 1] M.sub.x−mA.sub.yB.sub.z (M is at least one of Group I or Group II elements, A is at least one of Group III elements, B is at least one of Group V elements, x, y, and z are positive numbers which are determined according to stoichiometric ratios to ensure charge balance when m is 0, and 0<m<x), and having ferroelectric-like properties.

A proton-exchange-membrane fuel cell bipolar plate includes a metal substrate having a bulk portion and a surface portion including an anticorrosive, conductive binary phosphide material having a formula (I):
A.sub.xP.sub.y  (I),
where A is an alkali metal, alkaline earth metal, transition metal, post-transition metal, or metalloid, x, y is each a number independently selected from 1 to 15, and the binary phosphide material is configured to impart anticorrosive and conductive properties to the metal substrate.

A set of nanocrystals comprising a semiconductor comprising A representing a metal or metalloid in the +III oxidation state and B representing an element in the −III oxidation state, the nanocrystals being doped, on average per nanocrystal, by an atom of C chosen from the transition metals in the +I or +II oxidation state and various uses thereof.

Proposed are a layered compound having indium and phosphide, a nanosheet that may be prepared using the same, and an electrical device including the materials. Proposed is a layered compound represented by K.sub.1-xIn.sub.yP.sub.z (0≤x≤1.0, 0.75≤y≤1.25, 1.25≤z≤1.75).

Novel compounds with thermoelectric properties are presented. The novel compounds belong to the group of phosphides. They are characterized by excellent thermoelectric properties, in particularly in the temperature range of 400° C. to 700° C. Also a production method for the production of the compounds is presented, with which the thermoelectric substances can be prepared with high yield and quality.