64 results about "Lead telluride" patented technology

A process for synthesizing a metal telluride is provided that includes the dissolution of a metal precursor in a solvent containing a ligand to form a metal-ligand complex soluble in the solvent. The metal-ligand complex is then reacted with a telluride-containing reagent to form metal telluride domains having a mean linear dimension of from 2 to 40 nanometers. NaHTe represents a well-suited telluride reagent. A composition is provided that includes a plurality of metal telluride crystalline domains

(PbTe)_1-x-y(SnTe)_x(Bi₂Te₃)_y   (I)

having a mean linear dimension of from 2 to 40 nanometers inclusive where x is between 0 and 1 inclusive and y is between 0 and 1 inclusive with the proviso that x+y is less than or equal to 1. Each of the metal telluride crystalline domains has a surface passivated with a saccharide moiety or a polydentate carboxylate. A densified mass having a density of greater than 95% of the theoretical density includes a plurality of lead telluride, tin telluride, bismuth telluride, or a combination thereof of domains having a mean linear dimension of from 2 to 40 nanometers inclusive that have been subjected to hot isotactic pressing.

A segmented lead telluride egg-crate thermoelectric module. In preferred embodiments N legs and P legs are segmented into at least two segments. The segments are chosen for their figure of merit in the various temperature ranges between the hot side and the cold side of the module. In preferred embodiments a low-temperature egg-crate, molded from a liquid crystal polymer material, having very low thermal conductivity holds in place and provides insulation and electrical connections for the thermoelectric N legs and P legs at the cold side of the module. A castable ceramic capable of operation at temperatures in excess of 500° C. is used to provide electrical insulation between the legs at the hot side of the module.

A high-temperature thermoelectric module. The module includes a two part molded egg-crate for holding in place and providing insulation and electrical connections for a number of thermoelectric n-legs and p-legs. A first part of the egg-crate is comprised of a ceramic material capable of operation at temperatures in excess of 600° C. and a second part comprised of a thermoplastic material having very low thermal conductivity. In preferred embodiments the high temperature ceramic is zirconia and the thermoplastic material is DuPont Zenite. The thermoelectric legs are also comprised of high-temperature and low-temperature material. In preferred embodiments the high temperature thermoelectric material is lead telluride and the low temperature material is bismuth telluride. In preferred embodiments metal felt spacers are provided in each leg to maintain proper electrical contacts notwithstanding substantial temperature variations. Preferably the module is sealed in an inert gas filled insulating capsule.

A thermoelectric material and a method of using a thermoelectric material is provided. The thermoelectric material can include at least one compound. For example, the at least one compound may be a Group IV-VI compound such as lead telluride. The at least one compound may further include one or more dopants such as sodium, potassium, and thallium. The method of using a thermoelectric material can include exposing at least one portion of the at least one compound to a temperature greater than about 700 K.

A p- or n-conductive semiconductor material comprises a compound of the general formula Pb1-(x1+x2+ . . . +xn)A1x1A2x2 . . . AnxnTe1+z (I) where: in each case independently n is the number of chemical elements different from Pb and Te, 1 ppm<=x1 . . . xn<=0.05, -0.05<=z<=0.05 and n>=2, A1 . . . An are different from one another and are selected from the group of the elements Li, Na, K, Rb, Cs, Be, Mg, Ca, Sr, Ba, Al, Ga, In, Tl, Si, Ge, Sn, As, Sb, Bi, S, Se, Br, I, Sc, Y, La, Ti, Zr, Hf, V, Nb, Ta, Cr, Mo, W, Mn, Re, Fe, Ru, Os, Co, Rh, Ir, Ni, Pd, Pt, Cu, Ag, Au, Zn, Cd, Hg, Ce, Pr, Nd, Sm, Eu, Gd, Tb, Dy, Ho, Er, Tm, Yb, Lu or n=1, and A1 is selected from Ti, Zr, Ag, Hf, Cu, Gr, Nb, Ta.

The invention discloses a method for preparing nanometer crystal material of selenide and telluride, suitable for preparing nanometer crystal materials such as zinc selenide, lead selenide, cadmium selenide, cuprous selenide, zinc and cadmium selenide, silver telluride and lead telluride. The method is characterized by replacing water or organic solvent in the prior hydrothermal/solvent thermal synthetic method with fused compound hydroxide of alkali metals, and carrying out chemical reaction under normal pressure of temperature of 100 to 300 DEG C. All materials are soluble inorganic metal salts, selenide powders and telluride powders. The synthetic process has low cost; various parameters (such as temperature, pressure, concentration, etc.) in the reaction process are easy to monitor and control; the reaction system is good in uniformity, simple in technology and easy in production expansion. The obtained crystal products have good crystallinity, clean surface and uniform size, thus suitable for intrinsic property research and function exertion of the nanometer crystal material to the maximum limit.

The invention relates to a method for preparing block thermoelectric material of lead telluride base. Relevant salts are taken as raw materials, PbTe thermoelectric material containing Ag, Sb and Se is prepared by adopting a hydrothermal method combined with the technique of vacuum melting; the thermoelectric material refers to Ag1-xPbn-2SbTen-ySey, wherein, n is equal to or more than 12, x is equal to or more than 0 and less than 1 and y is equal to or more than 0 and equal to or less than 0.1n. The preparation method is as follows: firstly, a silver soluble salt, a lead soluble salt, a compound containing antimony, a compound containing tellurium, and selenium powder are taken as raw materials, alkali metal borohydride or diamide is taken as a reducing agent, the raw materials react at the temperature of 150 DEG C to 200 DEG C for 20 hours to 40 hours by adopting the hydrothermal method and lead telluride powder with impurities is prepared. Then, the obtained powder is put into a graphite crucible and sealed in a quartz glass tube under vacuum. The well-sealed glass tube is put into a resistance furnace with the temperature rising to 900 DEG C to 1000 DEG C, the heat is preserved for hours, then the temperature slowly drops to 450 DEG C which is kept for hours, and then the glass tube is cooled down to room temperature so as to obtain the compact block thermoelectric material. The preparation method of block thermoelectric material of telluride lead base is simple and economical and the prepared block thermoelectric material shows certain orientation and has fairly good thermoelectric property.

The invention discloses a method for leaching tellurium in tellurium slag in a co-oxidation mode. The method comprises the following steps that 1, sodium chloride is added into a sulfuric acid solution and heated to 60 DEG C-90 DEG C, heat preservation is conducted, then, ozone is introduced, the tellurium slag is added, and stirring is conducted; and 2, under the condition that stirring is kept, hydrogen peroxide is introduced into the solution processed in the step 1, the solution and the ozone are subjected to oxidizing leaching in a synergetic mode, and solid-liquid separation is conducted after reaction lasts for 2-8 h, so that leaching slag and leaching liquid containing the tellurium are obtained. According to the method for leaching the tellurium in the tellurium slag in the co-oxidation mode, hydroxyl radicals very high in oxidizing capacity are produced under an O3/H2O2 system; the stable structure of lead telluride and the stable structure of bismuthic acid copper are opened through the high oxidizing property of the hydroxyl radicals, so that the tellurium, bismuth and copper are exposed; the chlorine benignity characteristic of the tellurium and the bismuth is utilized, so that the leaching effect of the tellurium, the bismuth and the copper in the tellurium slag is good, the leaching rate of the tellurium reaches 99%, the leaching rate of the bismuth reaches 96%, and the leaching rate of the copper reaches 99%; and accordingly, the tellurium in the complex tellurium slag is efficiently and directly leached, and step-by-step recycling of the tellurium, the bismuth, the copper and antimony is facilitated.

The invention relates to a preparation method of a lead telluride nano-wire, belonging to the technical field of thermoelectric semiconductor materials, which comprises the following steps: first, prepare a Te nano-wire with the diameter of 3-20 nanometers; second, add Pb (NO3)2 with the same molar ratio with Na2TeO3 to the solution of Te nano-wire, seal in an autoclave at 90-100 DEG C to react for 9-12 hours, and get PbTe nano-wire with uniform diameter and the length of 1 micron to 100 microns. The preparation method of a lead telluride nano-wire has the advantages that: PbTe nano-wire with uniform diameter and average length smaller than the exciton Bohr radius can be produced through controlling the growth temperature, the lead salt concentration and the reaction time; the PbTe nano-wire prepared with the method can be used as an ideal scientific research material, laying good basis for preparing and realizing thermoelectric nanometer devices in the future.

A multi junction photovoltaic cell includes at least two P-N junctions electrically connected to each other in series. Each P-N junction includes a P-type absorber layer and a N-type emitter layer, each P-type absorber layer including a plurality of alternating thin film layers of zinc telluride and lead telluride, wherein zinc telluride and lead telluride have respective bandgaps when in bulk thickness and the effective bandgap of each P-type absorber layer is between the respective bandgaps, The effective bandgap of at least one P-type absorber layer is different from that of at least one other P-type absorber layer.

The invention discloses an infrared bandpass filter with a high squareness transmittance curve. The filter uses germanium as a base, zinc selenide and lead telluride as film materials, and is prepared by a vacuum thin film deposition method. The main film system adopts five resonant cavity precision film structure. It consists of a front film system, a substrate and a back film system. It has good band-pass transmission performance and can suppress optical radiation interference in other bands. It is applied to a space infrared scanning radiation instrument to meet the detection requirements for the infrared radiation of atmospheric targets.

The present invention relates to a multilayer compound synthetic furnace device, which is characterized in that an insulation layer (2), a heating wire (3), an insulation board (4) and a synthetic reaction tube (5) are arranged in a synthetic furnace (1), the furnace chamber of the synthetic furnace is divided into a plurality of synthetic chambers with the insulation board, and a plurality of synthetic reaction tubes (5) are put in each synthetic chamber, the thermal field temperature gradient of the furnace chamber is controlled in less or equal to plus or minus 5 DEG C, and each synthetic chamber being separated ensures the security during the synthetic process. The multilayer compound synthetic furnace device is applied to the synthesis of cadmium telluride, zinc telluride and lead telluride.

The invention belongs to the lead telluride (PbTe) thin film and nano powder preparation method field. In a low temperature aqueous solution synchronic synthesis method of PbTe thin film and nano powder, inorganic salt containing lead and tellurium dioxide or sodium tellurite are taken as raw materials, potassium borohydride or sodium borohydride is taken as reducing agent, and PbTe thin film and nano powder are simultaneously synthesized in alkaline aqueous solution at room temperature to 50 DEG C. The invention initially synthesizes PbTe thin film and nano powder at normal atmosphere and below 100 DEG C, the prepared thin film is flat, compact and uniform; and powder product is small in grain diameter uniform in grain fineness distribution, and grain diameter size can be controlled by controlling reaction temperature. The raw materials used in the whole technology are available, the technology is simple, scale production is easy to realize, and organic solvent is not used in the reaction process, thus being beneficial to environmental protection. The synthesized PbTe thin film and nano powder can be widely applied to thermoelectric device, solar battery, fluorescence device, infrared optical element, infrared thin film device, semiconductor detector and the like and has a wide application prospect.

A quantum nanomaterial having a bandgap that may be tuned to enable the quantum nanomaterial to detect IR radiation in selected regions including throughout the MWIR region and into the LWIR region is provided. The quantum nanomaterials may include tin telluride (SnTe) nanomaterials and/or lead tin telluride (Pb_xSn_1-xTe) nanomaterials. Additionally, a method of manufacturing nanomaterial that is tunable for detecting IR radiation in selected regions, such as throughout the MWIR region and into the LWIR region, is also provided.

The invention relates to a method for synthesizing a large-size lead telluride monocrystalline thermovoltaic material. According to the method, elemental tellurium and lead are served as raw materials, lead telluride polycrystalline positive and negative thermovoltaic materials are prepared firstly, and then, the large-size lead telluride thermovoltaic material is synthesized. During the preparation of the polycrystalline positive and negative thermovoltaic materials, the stoichiometric ratio of lead and the stoichiometric ratio of tellurium are 0.99: 1 and 1: 0.998 separately. During the synthesis of lead telluride, the polycrystalline positive and negative thermovoltaic materials are separately loaded into a large-size quartz growth ampule, and the large-size quartz growth ampule is vacuumized and sealed and then placed into a growth furnace. The bottommost end of the growth ampule is placed at a position of 30cm to 50cm of the furnace firstly, is slowly lowered at a rate of 0.3mm/hto 0.5mm/h after 30 to 50 hours of standing, is stopped lowering until the bottommost end of the quartz ampule reaches a position of 60cm to 80cm and is cooled, the growth ampule is taken out, the growth ampule goes through a high-temperature area, a gradient area and a low-temperature area along with change of a furnace-inside position, and the temperature range is 830 DEG C to 1,020 DEG C. According to the method, the blank in the prior art that lead telluride monocrystalline thermovoltaic materials cannot be produced in a large-size and large-scale manner is filled up. The product performance is stable and reliable, and the thermoelectric figure of merit (ZT value) reaches up to 1 or more.

This disclosure examines using lead telluride nanocrystals as well as other materials suitable for thermoelectric conversion, particularly materials with high Figure of Merit values, as coatings on flexible substrates. This disclosure also examines using flexible substrates with lead telluride nanocrystal coatings as sensors.

The invention relates to a high-performance environment-friendly sulfur group stannide thermoelectric material and a preparing method thereof. The chemical general formula of the thermoelectric material is Sn1.03-yMgyTe(Cu2Te)x(0<x<=0.05, 0<y<=0.12). According to the preparing method, a metal elementary substance with purity larger than 99% is used as a raw material, material matching is carried out according to the stoichiometric ratio of Sn1.03-yMgyTe(Cu2Te)x, after vacuum packaging, high-temperature melting and annealing heat treatment are carried out, the material is ground into powder, and after vacuum hot-press sintering and slow cooling are carried out, a sheet material is obtained and is the novel sulfur group stannide thermoelectric material of the target component. According to the design, in the SnTe material, collaborative optimization of an electrical transport property and a hot transport property is achieved to improve thermoelectric performance of the material. Compared with the prior art, the invention develops a novel high-performance environment-friendly Sn1.03-yMgyTe(Cu2Te)x thermoelectric material, the zT value reaches 1.4 at 900 K, and the material is an environment-friendly high-performance thermoelectric material with potentials for replacing a traditional p-type lead telluride material.

The invention discloses a far infrared wave band optical film optical filter with CVD diamond being a substrate. With lead telluride (PbTe) and zinc selenide (ZnSe) being a high-low refraction index film material, multiple layers of membranes are deposited on the two sides of the CVD diamond substrate by the adoption of a thermal evaporation deposition method in the vacuum environment of 1-2*103Pa and at the deposition temperature of 200+/-2 DEG C; with the far infrared optical filter, wave bands with wave length smaller than 5 micrometers can be intercepted, the average transmittance is lower than 1%, and the average transmittance of wave bands of 5-45 micrometers is larger than 71%. The far infrared wave band optical film optical filter can be applied to the fields of far infrared target recognition in earth radiation detection and deep space detection and other fields.

The invention provides a p-n-type lead telluride/polypyrrole double-layer thermoelectric film material and a preparation method thereof are disclose. That p-type lead telluride/polypyrrole double-layer thermoelectric film material is prepared by a hydrothermal method and a gas phase method. N-type lead telluride/polypyrrole bilayer thermoelectric thin film, the thickness of the lead telluride layer thin film is 20 nm-300 nm, and the thickness of the polypyrrole film is 20 nm-300nm. The lead telluride/polypyrrole double-layer thermoelectric thin film material prepared by the method has good thermoelectric performance, can be used for portable wireless sensor power supply, refrigeration of integrated circuit chips, refrigeration of light emitting diodes and photodetectors and other fields, has the advantages of simplicity, low cost, convenience and rapidity, and can be produced on a large scale.

The invention provides a lead selenide coated lead telluride dendritic crystal composite and a preparation method thereof, and relates to a thermoelectric material. The lead selenide coated lead telluride dendritic crystal composite and the preparation method provided by the invention have the advantages that the preparation method is low in reaction temperature, simple in process and friendly to environment, and the synthesized powder is high in purity and good in morphology. The lead selenide coated lead telluride dendritic crystal composite is composed of lead telluride and lead selenide, wherein PbTe in a stoichiometric proportion is coated with PbSe in a stoichiometric proportion. The preparation method comprises the steps that Pb(CH3COO)2.3H2O, TeO2 and SeO2 are dissolved in a sodium hydroxide aqueous solution in the mol ratio of Pb: Te: Se=2: 1: 1; NaBH4 is added to the solution and mixed together to obtain a precursor solution; next, the precursor solution is transferred into a reaction kettle and preserved with heat for 18-22 h at a temperature ranging from 160 to 200 DEG C and then the reaction is stopped; after the reaction temperature is reduced to the room temperature, precipitate is separated out, washed until neutrality and dried at a constant temperature; finally, the lead selenide coated lead telluride dendritic crystal composite is obtained.