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.

A method for producing metal chalcogenide nanoparticles, the method comprising: (i) producing hydrogen chalcogenide-containing vapor from a microbial source, wherein said microbial source comprises: (a) chalcogen-reducing microbes capable of producing hydrogen chalcogenide vapor from a chalcogen-containing source; (b) a culture medium suitable for sustaining said chalcogen-reducing microbes; (c) at least one chalcogen-containing compound that can be converted to hydrogen chalcogenide vapor by said chalcogen-reducing microbes; and (d) at least one nutritive compound that provides donatable electrons to said chalcogen-reducing microbes during consumption of the nutritive compound by said chalcogen-reducing microbes; and (ii) directing said hydrogen chalcogenide-containing vapor into a metal-containing solution comprising a metal salt dissolved in a solvent to produce metal chalcogenide nanoparticles in said solution, wherein said chalcogen is sulfur or selenium, and said chalcogenide is sulfide or selenide, respectively. The invention is also directed to metal chalcogenide nanoparticle compositions produced as above and having distinctive properties.

A thermoelectric conversion element includes a thermoelectric conversion material portion having a compound semiconductor composed of first base material element A and second base material element B and represented by A.sub.x-cB.sub.y with value of x being smaller by c with respect to a compound A.sub.xB.sub.y according to a stoichiometric ratio, a first electrode disposed in contact with the thermoelectric conversion material portion, and a second electrode disposed in contact with the thermoelectric conversion material portion and apart from the first electrode. An A-B phase diagram includes a first region corresponding to low temperature phase, second region corresponding to high temperature phase, and third region corresponding to coexisting phase, sandwiched between the low temperature phase and the high temperature phase, in which the low and high temperature phases coexist. A temperature at a boundary between the first region and the third region changes monotonically with a change in c.

A core shell quantum dot including a core including a first semiconductor nanocrystal and including zinc, tellurium, and selenium and a semiconductor nanocrystal shell disposed on the core and including a zinc chalcogenide, a method of manufacture thereof, and a device including the same are disclosed, wherein the core shell quantum dot does not include cadmium, lead, mercury, or a combination thereof, wherein in an X-ray photoelectron spectrum of the quantum dot, a peak area for Te oxide to a peak area for Te3d.sub.5/2 as an area percentage is less than or equal to about 25%.

A core shell quantum dot including a core including a first semiconductor nanocrystal and including zinc, tellurium, and selenium and a semiconductor nanocrystal shell disposed on the core and including a zinc chalcogenide, a method of manufacture thereof, and a device including the same are disclosed, wherein the core shell quantum dot does not include cadmium, lead, mercury, or a combination thereof, wherein in an X-ray photoelectron spectrum of the quantum dot, a peak area for Te oxide to a peak area for Te3d.sub.5/2 as an area percentage is less than or equal to about 25%.

A porous membrane comprising stacked layers of nanosheets, each nanosheet comprising one to three atomic layers of a 2D material comprising or consisting of one or more transition metal dichalcogenides is provided. The nanosheets have pores and the membrane comprises a network of water permeation pathways including through-pathways formed by the pores, horizontal pathways formed by gaps between the layers, and vertical pathways formed by gaps between adjacent nanosheets and stacking defects between the layers. Also provided is a method for making the membrane.

The present invention relates to a method for producing an InP-based quantum dot precursor from a phosphorus source and an indium source, in which a silylphosphine compound represented by the following Formula (1) with a content of a compound represented by the following Formula (2) of 0.3 mol % or less is used as the phosphorus source. Further, the present invention provides a method for producing an InP-based quantum dot comprising heating an InP quantum dot precursor to a temperature of 200° C. or more and 350° C. or less to obtain an InP quantum dot. ##STR00001##
(R is as defined in the specification.)

A quantum dot includes crystalline nanoparticle, wherein the quantum dot has a multi-layer structure including core particle and a plurality of layers on the core particle, and has Zn, S, Se, and Te as constituent elements, and the quantum dot has at least one quantum well structure in a radial direction from the center of the quantum dot. Therefore, quantum dots, which are crystalline nanoparticles, which do not contain harmful substances such as Cd and Pb, have excellent light emission characteristics such as half-value width at half maximum, and have high quantum efficiency.

Provided are a chalcogenide material, and a device and a memory device each including the same. The chalcogenide material may include: germanium (Ge) as a first component; arsenic (As) as a second component; at least one element selected from selenium (Se) and tellurium (Te) as a third component; and at least one element selected from the elements of Groups 2, 16, and 17 of the periodic table as a fourth component, wherein a content of the first component may be from 5 at % to 30 at %, a content of the second component may be from 20 at % to 40 at %, a content of the third component may be from 25 at % to 75 at %, and a content of the fourth component may be from 0.5 at % to 5 at %.

A thermoelectric conversion element includes a thermoelectric conversion material portion having a compound semiconductor composed of first base material element A and second base material element B and represented by A.sub.x-cB.sub.y with value of x being smaller by c with respect to a compound A.sub.xB.sub.y according to a stoichiometric ratio, a first electrode disposed in contact with the thermoelectric conversion material portion, and a second electrode disposed in contact with the thermoelectric conversion material portion and apart from the first electrode. An A-B phase diagram includes a first region corresponding to low temperature phase, second region corresponding to high temperature phase, and third region corresponding to coexisting phase, sandwiched between the low temperature phase and the high temperature phase, in which the low and high temperature phases coexist. A temperature at a boundary between the first region and the third region changes monotonically with a change in c.