7446-07-3

Basic information

• Product Name: Tellurium dioxide
• Synonyms: TELLURIUM(IV) OXIDE;TELLURIUM OXIDE;TELLERIUM OXIDE;TELLURIUM(+4)OXIDE;Tellurium oxide (TeO2);telluriumoxide(teo2);Tellurous acid anhydride;TeO2
• CAS NO: 7446-07-3
• Molecular Formula: O₂Te
• Molecular Weight: 159.6
• EINECS: 231-193-1
• Product Categories: Inorganics;Metal and Ceramic Science;Oxides;Tellurium;metal oxide
• Mol File: 7446-07-3.mol
• Article Data: 75

Chemical Properties

• Melting Point: 733 °C(lit.)
• Boiling Point: 1245 °C
• Appearance: White to slightly yellow/Powder
• Density: 5.67 g/mL at 25 °C(lit.)
• Vapor Pressure: 0Pa at 25℃
• Storage Temp.: Storage temperature: no restrictions.
• Water Solubility: insoluble
• Stability: Stable. Incompatible with strong acids, strong oxidizing agents.
• Merck: 14,9123
• CAS DataBase Reference: Tellurium dioxide(CAS DataBase Reference)
• NIST Chemistry Reference: Tellurium dioxide(7446-07-3)
• EPA Substance Registry System: Tellurium dioxide(7446-07-3)

Safety Data

• Safety Statements: 24/25
• RIDADR: UN 3284 6.1/PG 3
• WGK Germany: 2
• RTECS: WY2675000
• TSCA: Yes
• HazardClass: 6.1(a)
• PackingGroup: II
• Hazardous Substances Data: 7446-07-3(Hazardous Substances Data)

Usage

Chemical Properties

Heavy, white, crystalline powder; odorless. Soluble in concentrated acids, alkalies; slightly soluble in dilute acids, water.

Physical properties

White crystals; dimorphic; exists in tetragonal and orthorhombic forms; density 5.75 g/cm3 (tetragonal), 6.04 g/cm3 (orthorhombic); melts at 733°C forming a deep yellow liquid; vaporizes at 1,245°C; insoluble in water; soluble in acids and alkalies.

Uses

Different sources of media describe the Uses of 7446-07-3 differently. You can refer to the following data:
1. Tellurium dioxide is also used in devices which can convert light into sound (acousto-optic material). Glasses made of tellurium oxide have high refractive indices and transmit into mid-IR region. It is used to make glasses with special properties. It is useful in optical waveguides and optical fiber amplification.
2. Tellurium dioxide is used to prepare tellurium metal, telluric acid, and many tellurium salts. It may also be used in the preparation of Ag2Te nanoparticles.
3. TeO2 can be potentially used in medical imaging and industrial monitoring processes.

Production Methods

Tellurium dioxide in its orthorhombic form occurs in nature as mineral tellurite. It is mined from natural deposits. Also, tellurium dioxide is produced as an intermediate during recovery of tellurium metal from anode slimes of electrolytic copper refining (See Tellurium, Production). The dioxide also is prepared by treating tellurium metal with hot nitric acid to form 2TeO2?HNO3. The product then is heated to drive off nitric acid.

General Description

Tellurium dioxide (TeO2) is a ceramic material that can be used as a semiconducting oxide. It has a wide band gap and high mobility as determined by density functional theory (DFT) calculations. In bulk quantity, it exists in two polymorphs which include tetragonal α-TeO2 and orthorhombic β-TeO2.

Flammability and Explosibility

Nonflammable

Safety Profile

Poison by intratracheal route. An experimental teratogen. Experimental reproductive effects. When heated to decomposition it emits toxic fumes of Te. See also TELLURIUM COMPOUNDS.

Purification Methods

Dissolve it in 5M NaOH, filter it and precipitate it by adding 10M HNO3 to the filtrate until the solution is acid to phenolphthalein. After decanting the supernatant, the precipitate is washed five times with distilled water, then dried for 24hours at 110o [Horner & Leonhard J Am Chem Soc 74 3694 1952].

InChI:InChI=1/O2Te/c1-3-2

Synthetic route

tellurium dichloride (10025-71-5) + dinitrogen tetraoxide (10544-72-6) → tellurium(IV) oxide (7446-07-3)

Conditions	Yield
In neat (no solvent) byproducts: NOCl; reaction of TeCl2 with liquid N2O4;;	100%

tellurium trisulfide → tellurium(IV) oxide (7446-07-3)

Conditions	Yield
With air In neat (no solvent) heating in air above 430°C; at 630.degree C complete conversion;;	100%

tellurium → tellurium(IV) oxide (7446-07-3)

Conditions	Yield
In hydrogenchloride Electrochem. Process; anodic dissolution of Te in 6n HCl in a cell with ceramic diaphragma, neutralisation with aq. NH3;; pure;;	98%
In hydrogenchloride byproducts: H6TeO6; Electrolysis; electrolysis in HCl acidic soln. at 25 °C with a Te-anode;;
With calcium oxide In neat (no solvent) byproducts: CaTeO3, Ca3TeO6; oxidation of Te in air in presence of CaO at 100-800°C;;

tellurium + potassium nitrate → tellurium(IV) oxide (7446-07-3)

Conditions	Yield
In melt Te and KNO3 were molten for 2 h at 400-430 °C (molar ratio 1/2-2.5), the melt was dissolved in aq. KOH(10%) forming K2TeO3 which was treated with HNO3;;	97.5%

tellurium + sodium nitrate (7631-99-4) → tellurium(IV) oxide (7446-07-3)

Conditions	Yield
In melt Te and NaNO3 were molten for 2 h at 400-430 °C (molar ratio 1/2-2.5), the melt was dissolved in aq. KOH(10%) forming K2TeO3 which was treated with HNO3;;	97.5%

tellurium + barium(II) nitrate → tellurium(IV) oxide (7446-07-3)

Conditions	Yield
In melt byproducts: BaTeO3, Ba3TeO6; melting of a mixture of Te and anhydrous Ba(NO3)2 (in 10% excess) at temp. between 400 and 550°C; oxidation of Te starts at 345-400°C, at 650°C 65% TeO2 was formed;;	65%

barium(II) chloride dihydrate (10361-37-2) + ammonium chloride + orthotelluric acid (7803-68-1) + copper(II) oxide → tellurium(IV) oxide (7446-07-3) + Cu2Te3O8 + Ba2Cu4Te4O11Cl4

Conditions	Yield
In water molar ratio Ba:Cu:Te=1:2:2, excess 2 M aq. NH4Cl, sealed silica tube, 375°C, 5 d; collection (filtration), washing (water, Me2CO), hand sepn.;	A n/a B n/a C 30%

sodium tellurate → tellurium(IV) oxide (7446-07-3)

Conditions	Yield
With sulfur In neat (no solvent) reduction with S;;

cerium telluride → tellurium(IV) oxide (7446-07-3)

Conditions	Yield
With air In neat (no solvent) byproducts: CeO2; CeTe was heated in air;;
In neat (no solvent)

cerium telluride + water (7732-18-5) → tellurium(IV) oxide (7446-07-3)

Conditions	Yield
In neat (no solvent) byproducts: Ce(OH)3; Te was heated in a stream of H2O vapor with ignition;;
In neat (no solvent)

potassium tellurite → tellurium(IV) oxide (7446-07-3)

Conditions	Yield
In water pptn. from Na2TeO3-soln. with HNO3 at 100 °C and pH 3.5-4.0 at the end of the pptn.;; purity: 99.85-99.95%;;
In water air introducing;
In water air introducing;

potassium tellurite → tellurium + tellurium(IV) oxide (7446-07-3)

Conditions	Yield
With potassium hydroxide; hydrazine hydrate In water Kinetics; components soln. mixing (pH 9.3 (KOH), conct. temp. in range 18-80°C), pptn.; ppt. filtration off, washing (6% HNO3 to remove TeO2); chem. anal.;

2K(1+)*Te(NH)3(2-)=K2{Te(NH)3} + water (7732-18-5) + acetic acid (64-19-7) → tellurium(IV) oxide (7446-07-3)

Conditions	Yield
In not given hydrolysis of K2(Te(NH)3) (moistened with benzene) with acetic acid under exclusion of air forms TeO2*H2O; loss of H2O on heating;;

tellurium + water (7732-18-5) → tellurium(IV) oxide (7446-07-3)

Conditions	Yield
In nitric acid disssolving finely powdered, distillated Te with small amount of water in aq. HNO3; evapn. on water bath; heating residue;;	>99
In water byproducts: H2; from metallic Te and dry air; heating to 160°C;; formation of TeO2 at surface of Te;;
In water byproducts: H2; from metallic Te and dry air; heating to 160°C;; formation of TeO2 at surface of Te;;
In nitric acid aq. HNO3; disssolving finely powdered, distillated Te with small amount of water in aq. HNO3; evapn. on water bath; heating residue;;	>99

tellurium + water (7732-18-5) + oxygen (80937-33-3) → tellurium(IV) oxide (7446-07-3)

Conditions	Yield
In water Te was heated with H2O and O2 under pressure (60 atm) at 150°C;; the formed solid phase is a mixture of TeO2 and Te;;

CaF2*TeBr4 + water (7732-18-5) → tellurium(IV) oxide (7446-07-3)

Conditions	Yield
In water byproducts: HBr, CaF2; hydrolysis;;

water (7732-18-5) + tellurium tetrachloride (10026-07-0) → tellurium(IV) oxide (7446-07-3)

Conditions	Yield
In water byproducts: HCl; hydrolysis with H2O;;
In water precipitation of TeO2 on cooling a soln. of TeCl4 in boiling H2O;; impurities of a basic salt;;
In water precipitation of TeO2 on cooling a soln. of TeCl4 in boiling H2O;; impurities of a basic salt;;

tetrakis(pentafluorophenyl)tellurium(IV) (18064-83-0) + water (7732-18-5) → tellurium(IV) oxide (7446-07-3)

Conditions	Yield
In further solvent(s) byproducts: C6F5H; in EtCN;

TeF4*SbF5 (20587-27-3) + water (7732-18-5) → tellurium(IV) oxide (7446-07-3)

Conditions	Yield
In not given

2H(1+)*TeCl6(2-)*4(CH3)2SO=H2TeCl6*4(CH3)2SO + water (7732-18-5) → tellurium(IV) oxide (7446-07-3)

Conditions	Yield
byproducts: HCl, (CH3)2SO; hydrolysis;;

tellurium(VI) oxide (13451-18-8) → tellurium(IV) oxide (7446-07-3)

Conditions	Yield
In neat (no solvent) heating at 430°C;;
In neat (no solvent) decomposition of β-TeO3 started at 350 °C, the reaction is at 600 °C complete (in presence of Na2CO3 at 700 °C);;	>99
In neat (no solvent) decomposition of β-TeO3 started at 350 °C, the reaction is at 600 °C complete (in presence of Na2CO3 at 700 °C);;	>99
In neat (no solvent) byproducts: O2; decomposition of β-TeO3 started at 430°C, the reaction is at 580°C complete;;	>99
In neat (no solvent) isothermal heating at (520+/-10)°C for 120 h in air; X-ray diffraction;

telluric acid (13520-55-3) → tellurium(IV) oxide (7446-07-3)

Conditions	Yield
With osmium In neat (no solvent) byproducts: OsO4; reduction at red heat;;

tellurium + telluric acid (13520-55-3) → tellurium(IV) oxide (7446-07-3)

Conditions	Yield
In neat (no solvent) oxidation of Te with H2TeO4;;

barium metatellurite → tellurium(IV) oxide (7446-07-3)

Conditions	Yield
In neat (no solvent) decomposition at 840°C;;

zinc tellurate → tellurium(IV) oxide (7446-07-3) + zinc tellurate + oxygen (80937-33-3)

Conditions	Yield
In neat (no solvent) 800-900 K;

cesium hexaiodotellurate (IV) → tellurium(IV) oxide (7446-07-3) + tellurium(IV) iodide (7790-48-9)

Conditions	Yield
In neat (no solvent) byproducts: CsCl; decomposition on heating at 260, 300 or 350°C;;

tellurium + silver(I) chloride → tellurium(IV) oxide (7446-07-3) + silver telluride + silver tellurite

Conditions	Yield
In ammonia byproducts: HNO3, Ag; in aq. NH3 soln.; with excess of Ag(1+) salts;; separation of Ag2TeO3 by washing with aq. NH3;;

tellurium + silver(I) chloride → tellurium(IV) oxide (7446-07-3) + silver telluride

Conditions	Yield
In ammonia byproducts: HNO3; in aq. NH3 soln.;;

cadmium telluride → tellurium(IV) oxide (7446-07-3) + cadmium tellurate(IV)

Conditions	Yield
In neat (no solvent) Kinetics; heating at 350-500 ° C; IR;

mercury(II) oxide + tellurium(IV) iodide (7790-48-9) → tellurium(IV) oxide (7446-07-3)

Conditions	Yield
In neat (no solvent) byproducts: HgI2;

tellurium(IV) oxide (7446-07-3) + Carbonyl fluoride (353-50-4) → carbon dioxide (124-38-9) + tellurium(IV) fluoride (15192-26-4)

Conditions	Yield
In neat (no solvent) slight excess over the stoich. amt. of COF2 required; reaction mixt. heated in a stainless steel or monel cylinder at 160°C for 56 h;	A n/a B 100%

nickel(II) oxide (1313-99-1) + tellurium(IV) oxide (7446-07-3) → Ni2Te3O8

Conditions	Yield
With NH4Cl In water High Pressure; heating (sealed silica tube, 375°C, 3-5 d);	99%
In neat (no solvent) byproducts: NiTe2O5; NiO and TeO2 were heated in a stream of N2 at 550-800 °C;; polluted with NiTe2O5:;
In neat (no solvent) NiO and TeO2 were heated in a stream of N2 at 550-800 °C, molten at 900°C for 20 min in goldplate covers;; pure;;

tellurium(IV) oxide (7446-07-3) + cadmium(II) oxide + cadmium(II) chloride (10108-64-2) → Cd7Cl8(Te7O17)

Conditions	Yield
In neat (no solvent, solid phase) at 720°C for 6 d;	99%
With Er2O3 In neat (no solvent, solid phase) ground, pressed, sealed, heated at 720°C for 6 d; cooled to 300°C at 4°C/h;

tellurium(IV) oxide (7446-07-3) + cadmium(II) oxide + cadmium(II) chloride (10108-64-2) → [Cd2(Te6O13)][Cd2Cl6]

Conditions	Yield
In neat (no solvent, solid phase) at 670°C for 6 d;	99%

samarium(III) oxide + tellurium(IV) oxide (7446-07-3) + manganese(ll) chloride → Sm2MnTe5O13Cl2

Conditions	Yield
In neat (no solvent) the mixt. Sm2O3/MnCl2/TeO2 1:1:5 was ground and pressed into a pellet, sealed into an evacuated quartz tube, heated at 700°C for 6 days, cooled to 500°C at 4.17°C/h before switching off the furnace; XRD powder diffraction;	99%

tellurium(IV) oxide (7446-07-3) + zinc(II) oxide → zinc pyrotellurite

Conditions	Yield
With NH4Cl In water byproducts: ZnTeO3; High Pressure; heating (sealed silica tube, 375°C, 3-5 d);	99%
In neat (no solvent) mixed, homogenized, sealed under vac., heated at 50 °C lower thenmelting temp. of tellurate(IV) for 5 h, ground, resealed under vac., he at treated, procedure repeated three times;
With PVA In neat (no solvent, solid phase) mixt. ZnO and TeO2 was ball-milled in MeOH for 24 h, dried at 80°C overnight, calcined at 560°C for 19 h, remilled, PVA was added,pressed at 140 MPa, heated at 400°C for 6 h and sintered at 610. degree.C for 2 h; X-ray diffraction;

strontium(II) oxide + tellurium(IV) oxide (7446-07-3) + strontium chloride → Sr4(Te3O8)Cl4

Conditions	Yield
In neat (no solvent, solid phase) by a react. of SrO, SrCl2 and TeO2 in a molar ratio of 2:2:3 at 720°C for 6 d; identified by XRD and EDS anal.;	99%
In neat (no solvent, solid phase) by a react. of SrO (0.8 mmol), SrCl2 (0.4 mmol) and TeO2 (1.2 mmol); themixt. was ground and pressed into a pellet; heating in an evacuated qua rtz tube at 660°C for 6 d; cooling to 300°C at 4°C/h before switching off the furnace; identified by XRD and EDS anal.;

tellurium(IV) oxide (7446-07-3) + neodymium(III) oxide + neodymium oxide chloride (13759-26-7) + copper(l) chloride → Nd4CuTe5O15Cl3

Conditions	Yield
In neat (no solvent) the mixt. NdOCl/Nd2O3/CuCl/TeO2 2:1:1:5 was ground and pressed into a pellet, sealed into an evacuated quartz tube, heated at 650°C for 6days, cooled to 500°C at 4.17°C/h before switching off th e furnace; XRD powder diffraction;	99%

nickel(II) oxide (1313-99-1) + tellurium(IV) oxide (7446-07-3) + molybdenum(VI) oxide → 3Ni(2+)*MoO4(2-)*2TeO3(2-)=Ni3(MoO4)(TeO3)2

Conditions	Yield
In neat (no solvent, solid phase) mixt. of MoO3, NiO and TeO2 ground; pressed into pellet; sealed in evacuated quartz tube; heated at 720°C for 6 d; cooled to 270°C(4.5°C/h); crystals isolated; elem. anal.;	99%

niobium(V) oxide + tellurium(IV) oxide (7446-07-3) + potassium carbonate (584-08-7) → KNb3O6(tellurite)2

Conditions	Yield
In neat (no solvent, solid phase) heating 1:3:4 mixt. of K2CO3, Nb2O5 and TeO2 at slightly lower than 800°C for 5 ds; powder XRD;	99%

tantalum(V) oxide + tellurium(IV) oxide (7446-07-3) + potassium carbonate (584-08-7) → KTa3O6(tellurite)2

Conditions	Yield
In neat (no solvent, solid phase) heating 1:3:4 mixt. of K2CO3, Ta2O5 and TeO2 at slightly lower than 800°C for 5 ds; powder XRD;	99%

rubidium carbonate + niobium(V) oxide + tellurium(IV) oxide (7446-07-3) → RbNb3O6(tellurite)2

Conditions	Yield
In neat (no solvent, solid phase) heating 1:3:4 mixt. of Rb2CO3, Nb2O5 and TeO2 at slightly lower than 820°C for 5 ds; powder XRD;	99%
In neat (no solvent, solid phase) grinding 1:3:13 mixt. of Rb2CO3, Nb2O5 and TeO2, pressing into pellets, heating at 820°C for 5 ds; cooling to 300°C at rate of 4°C/h, XRD;

niobium(V) oxide + tellurium(IV) oxide (7446-07-3) + caesium carbonate (534-17-8) → Cs3Nb9TeO26(tellurite)2

Conditions	Yield
In neat (no solvent, solid phase) heating 3:9:8 mixt. of Rb2CO3, Ta2O5 and TeO2 at slightly lower than 810°C for 5 ds; powder XRD;	99%
In neat (no solvent, solid phase) grinding 1:2.66:10 mixt. of Cs2CO3, Nb2O5 and TeO2, pressing into pellets, heating at 810°C for 5 ds; cooling to 300°C at rate of 4°C/h, XRD;

rubidium carbonate + tantalum(V) oxide + tellurium(IV) oxide (7446-07-3) → RbTa3O6(tellurite)2

Conditions	Yield
In neat (no solvent, solid phase) heating 1:3:4 mixt. of Rb2CO3, Ta2O5 and TeO2 at slightly lower than 840°C for 5 ds; powder XRD;	99%
In neat (no solvent, solid phase) grinding 1:3:13 mixt. of Rb2CO3, Ta2O5 and TeO2, pressing into pellets, heating at 840°C for 5 ds; cooling to 300°C at rate of 4°C/h, XRD;

tellurium(IV) oxide (7446-07-3) → tellurium

Conditions	Yield
With HCl In hydrogenchloride saturated with H2Te at a pH of 5.0-6.3, 200-250°C, 50-100 MPa;	98%
With ethylene glycol In ethylene glycol other Radiation; mixture of ethylene glycol and TeO2 put into microwave oven; heated to 185°C; held at this temp. for 30 min; centrifuged; washed with absolute ethanol several times; dried at 80°C in vacuum;	90%
With silver In neat (no solvent) reduction of TeO2 with Ag;;

tellurium(IV) oxide (7446-07-3) + sodium carbonate (497-19-8) → sodium tellurate + sodium tellurite

Conditions	Yield
In neat (no solvent) heating of equimolar amounts of TeO2 and Na2CO3 at 540 °C in presence of air;;	A 98% B n/a
In neat (no solvent) heating of equimolar amounts of TeO2 and Na2CO3 at 540 °C in presence of air;;	A 98% B n/a
In neat (no solvent) heating of equimolar amounts of TeO2 and Na2CO3 at 480-620 °C in presence of air;;

tellurium(IV) oxide (7446-07-3) + sodium molybdate dihydrate (7631-95-0) → Na2MoTe4O12

Conditions	Yield
In water molar ratio Mo:Te=3:1, acid digestion bomb, 225°C, 4 d; then cooling to room temp. over 36 h;	98%
In neat (no solvent, solid phase) stoich. amts., heating in air (450°C, 6 h; then 625°C, 2 d; intermittent grinding);

tellurium(IV) oxide (7446-07-3) + calcium hydroxide → calcium tellurate

Conditions	Yield
In neat (no solvent) heating between 975 and 1078°C;; dependence of temp., time and conc. of educts; acceleration by addn. of Na2CO3;;	98%
In neat (no solvent)

tellurium(IV) oxide (7446-07-3) + barium hydroxide octahydrate → barium tellurite

Conditions	Yield
With HNO3 In water to the mixt. of Ba, Te comp. and water placed in steel bomb concd. HNO3 was added dropwise to pH ca. 10, mixt. was heated to 180°C for 5 d; solid was recovered by vac. filtration, washed with water and acetone; XRD;	98%

tellurium(IV) oxide (7446-07-3) + sodium tungstate (VI) dihydrate (10213-10-2) → Na2WTe4O12

Conditions	Yield
In water molar ratio W:Te=3:1, acid digestion bomb, 225°C, 4 d; then cooling to room temp. over 36 h;	96%
In neat (no solvent, solid phase) stoich. amts., heating in air (450°C, 6 h; then 580°C, 2 d; intermittent grinding);

tellurium(IV) oxide (7446-07-3) + cadmium(II) sulphide → cadmium telluride

Conditions	Yield
In neat (no solvent) byproducts: SO2; TeO2 was heated with CdS at 600-800°C;;	95.7%
In neat (no solvent) byproducts: SO2; TeO2 was heated with CdS at 600-800°C;;	95.7%

tellurium(IV) oxide (7446-07-3) + 1,1,3,3-tetramethyl-2-thiourea (2782-91-4) + hydrogen iodide (10034-85-2) → Te2(tetramethylthiourea)2I4 (110591-82-7)

Conditions	Yield
In hydrogenchloride; methanol; N,N-dimethyl-formamide to TeO2 dissolved in hot HCl were added with swirling, a hot soln. of tmtu in DMF, then a hot mixt. of HI and MeOH was added, the soln. was kept hot for ca. 30 min, allowed to cool to room temp.; the crystals were filtered, washed with MeOH, then with diethyl ether, recrystd. in DMF/HI, filtered, a hot MeOH was added; elem. anal.;	95%

tellurium(IV) oxide (7446-07-3) + boron tribromide (10294-33-4) → tellurium(IV) tetrabromide (10031-27-3)

Conditions	Yield
In neat (no solvent) heated at 110-120°C for 5 h;;	91%
In neat (no solvent) heated at 110-120°C for 5 h;;	91%

tellurium(IV) oxide (7446-07-3) + hexaammonium heptamolybdate(6-)-water (1/4) → 2NH4(1+)*Mo3TeO12(2-)=(NH4)2Mo3TeO12 + 4NH4(1+)*Mo6TeO22(4-)*2H2O=(NH4)4Mo6TeO22*2H2O

Conditions	Yield
In water molar ratio NH4:Mo:Te=5.14:6:1, closed vessel, 225°C. 14 d;	A 91% B n/a
In water molar ratio NH4:Mo:Te=5.14:6:1, closed vessel, 225°C. 7 d, cooling to room temp. over 2 d; hand sepn. of products;	A 87.5% B n/a
In water molar ratio NH4:Mo:Te=2.57:3:1, closed vessel, 225°C. 7 d; further unidentified product;	A 41% B n/a
In water molar ratio NH4:Mo:Te=1.71:2:1, closed vessel, 225°C. 7 d; further unidentified product;

potassium fluoride + tellurium(IV) oxide (7446-07-3) → potassium hydroxofluorotellurate(IV)

Conditions	Yield
In hydrogen fluoride addn. KF to suspn. TeO2F2 (prepared from TeO2 in 40% aq. HF) with TeO2:KF ratio = 1:1, pptn.; ppt. sepd. from mother liquor, washed (alcohol), dried (air), elem. anal.;	90%

Upstream product

• 12014-97-0 cerium telluride 
• 7732-18-5 water 
• 10026-07-0 tellurium tetrachloride 
• 67-68-5 dimethyl sulfoxide 
• 18879-38-4 dimethyl tellurium diiodide 
• 7697-37-2 nitric acid 
• 14683-12-6 tellurium 
• 7783-97-3 silver(I) iodate 
• 7446-08-4 selenium(IV) oxide 
• 12029-98-0 iodine pentoxide 
• 7646-93-7 potassium hydrogensulfate 
• 80937-33-3 oxygen 
• 7631-99-4 sodium nitrate 
• 124-38-9 carbon dioxide 

Downstream Products

• 516481-63-3 2-[4-(4-chlorobenzenesulfinyl)phenyl]-1H-benzimidazole-5-carboxylic acid 
• 10026-07-0 tellurium tetrachloride 
• 10049-23-7 tellurous acid 
• 13451-14-4 telluric acid dihydrate 
• 15852-22-9 tellurite^(2-) 
• 14683-12-6 tellurium 
• 7727-37-9 nitrogen 
• 13494-80-9 hydrogen telluride 
• 124-38-9 carbon dioxide 
• 7664-93-9 sulfuric acid 
• 98517-27-2 tellurium oxide⁽¹⁺⁾ 
• 98517-28-3 tellurium dioxide⁽¹⁺⁾ 
• 13451-18-8 tellurium oxide 
• 7783-80-4 tellurium hexafluoride 

Relevant articles and documents

Structural and thermal studies on PuTe2O6

PuTe2O6 was synthesised by the solid state reaction route and characterized by X-ray diffraction and thermal methods. The structure of PuTe2O6 was derived by the Rietveld analysis of X-ray powder diffraction data in the monoclinic system with cell parameters a = 0.69937(1), b = 1.10014(2), c = 0.73404(2) nm, β = 107.98(2)°, Z = 4 in the space group P21/n. In the structure, each plutonium atom is coordinated to eight oxygen atoms. The structure is made up of zigzag strings of PuO8 distorted edge-sharing polyhedron parallel to the a axis. Tellurium atoms are coordinated to three oxygen atoms. PuTe2O6 melts at 1125 K incongruently and decomposes according to the reaction: PuTe2O6(s) → PuO2(s) + 2TeO2(g). The kinetics of decomposition under isothermal heating conditions in flowing air were studied to determine the rate constants, activation energy and reaction mechanism.

Standard enthalpies of formation of tellurium compounds. I. Tellurium dioxide

The enthalpy of formation of TeO2(s) has been obtained by solution calorimetry using two independent thermochemical cycles: the first, in -3 H2SO4 + 0.10 mol * dm-3 K2Cr2O7 + 0.010 mol * dm-3 MnSO4>(aq), based

Standard molar Gibbs energy of formation of Ba3Te2O9(s) by transpiration technique

The standard molar Gibbs energy of formation of barium tellurite, Ba3Te2O9(s), was determined by the transpiration technique using pure oxygen as the carrier gas in the temperature range from 1119 to 1280 K. The condensate

Thermodynamic stability of Sm2TeO6

The vapour pressure of Sm2TeO6 was measured using a thermal analyser with a horizontal arm. This TG based transpiration technique, was validated by measuring the vapour pressure of pure TeO2(s). The temperature dependence of the latter was measured to be log p (Pa) = {14.2 - 13321/T (K)} (±0.03) in the range 884-987 K. These data yielded a Δ H298 ° value of 269.7 ± 0.6 kJ mol-1 for the enthalpy of sublimation (third-law method) of TeO2 which compared well with the data reported in the literature. The temperature dependence of the vapour pressure of TeO2 over the mixture Sm2TeO6(s) + Sm2O3(s) generated by the incongruent vapourisation reaction,Sm2TeO6(s) → Sm2O3(s) + TeO2(g) + 1/2O2(g)could be expressed aslog p (Pa) = { 18.56 - 25469 / T (K) } ± 0.06 (1374 - 1533 K). The standard Gibbs energy of formation of Sm2TeO6(s) was derived from the above vapour pressure data in conjunction with auxiliary data for the other coexisting phases. The temperature dependence of the Gibbs energy of formation of Sm2TeO6 over the temperature range 1374-1533 K could be represented asΔ Gf ° (S m2 Te O6) (kJ mo l- 1) = { - 2399.3 + 0.5714 T (K) } ± 5.8. The Gibbs energy of formation of Sm2TeO6(s) is being reported for the first time.

X-ray and thermal investigations of LaFeTeO6 and LaCrTeO6 compounds

LaFeTeO6 and LaCrTeO6 were prepared by the solid-state reaction of La2O3, M2O3 (M = Fe or Cr) and TeO2 in 1:1:2 molar ratio. The compounds were characterised by X-ray and thermogravimetric techniques. Thermal and X-ray studies indicated that LaFeTeO6 and LaCrTeO6 vapourize incongruently according to the reactions:{A formula is presented}{A formula is presented}X-ray diffraction data of both the compounds have been indexed on the hexagonal system. Vapour pressures of TeO2(g) over LaFeO3(s) and LaCrO3(s) were independently measured by employing the Knudsen effusion mass loss (KEML) technique. From the partial pressures of TeO2(g) measured, the standard Gibbs free energy of formation of (ΔfG°) LaFeTeO6(s) and LaCrTeO6(s) were obtained and could be represented by the following relations:{A formula is presented}.

New glasses within the Tl2O-Ag2O-TeO2 system: Thermal characteristics, Raman spectra and structural properties

Within the Tl2O-Ag2O-TeO2 system, a large glass-forming domain was evidenced and is presented for the fist time. Densities, glass transition (Tg) and crystallization (Tc) temperatures of the relevant glasses were measured. A structural approach of these glasses as functions of the composition was performed using Raman scattering. The Raman spectra were analysed in terms of the structural modifications induced by the Tl2O and Ag2O modifiers. It has clearly evidenced a phase separation inherent in tellurite glasses with low valence cations (as Tl+ and Ag+). The glasses would be constituted of two phases only: one of pure TeO2 and one of pure ortho-tellurite M2TeO3 (M = Ag, Tl) with the statistically mixed Ag-Tl cationic composition.

Ag2Te2O7, a novel silver tellurate of Weberite structure type

Ag2Te2O7 has been synthesized by solid state reaction of Ag2O and TeO2 under elevated oxygen pressure. The compound is diamagnetic and insulating, and decomposes at 560 °C in an Ar atmosphere into oxygen, Ag2TeO3 and TeO2. Ag2Te2O7 crystallizes orthorhombic in space group Imma with a = 7.266(2), b = 10.1430(9), c = 7.6021(17) A, V = 560.3(2) A3, Z = 4, 410 independent reflections, R1 = 4.65 %, wR2 = 11.13%. The crystal structure consists of a three-dimensional framework of TeO6 octahedra which are linked by common vertices. Voids of the framework accommodate silver atoms which are coordinated by eight oxygen atoms. The structure derives from that one of naturally occurring Weberite, Na2MgAlF7. The relationship to the pyrochlore structure type is discussed.

125Te and 129I Moessbauer Spectroscopic Studies of the Tetragonal and Orthorhombic Forms of Tellurium(IV) Oxide

125Te and 129I Moessbauer spectra have been measured for the tetragonal (α) and orthorhombic (β) forms of TeO2.The Moessbauer data show that there are no significant differences between the two modification in either the electronic structure or the chemic

New vanadium(IV) and titanium(IV) oxyfluorotellurates(IV): V 2Te2O7F2 and TiTeO3F 2

Titanium(IV) tellurium(IV) trioxide difluoride, TiTeO3F2, and divanadium(IV) ditellurium(IV) heptaoxide difluoride, V2Te2O7F2, were characterized. The Te, Ti, one F and two O atoms are on g

Study of the formation of bi2te4o11

The solid state reaction in a 1:4 mole ratio mixture of Bi2O3 and TeO2 and the polymorphic phase transition of Bi2Te4O11 have been investigated using differential scanning calorimetry (DSC), electron microprobe, X-ray powder diffraction (XPD), and selected area electron diffraction (SAED) analysis in the 25-730°C temperature range. Upon heating first a 8Bi2Te4O11 + 23TeO2 eutectic is formed, which melts at 598.9°C. In this melt the excess of Bi2O3 reacts further and the Bi2O3 + 4TeO2 = Bi2Te4O11 reaction takes place. The cubic modification is formed by fast crystallization of the Bi2Te4O11 melt. The structure of the cubic Bi2Te4O11 can be characterized by the lattice constant of a = 5.6397(5) A and space group Fm3m. The main product of a slow cooling is the same cubic polymorph although a subordinate formation of the monoclinic phase is also observed. The β-Bi2Te4O11 cubic phase undergoes a monotropic transformation into the α-Bi2Te4O11 monoclinic modification at temperatures higher than 400°C. The cubic → monoclinic transition is the result of an ordering in one set of {111} planes and the orthogonality of the cubic phase in the [110] projection changes to monoclinic symmetry. The melting enthalpies of the cubic β-phase and the monoclinic α-phase are 35.9 ± 3.3 J/g and 84.3 ± 4.3 J/g respectively.

Structural and thermochemical studies on Cr2TeO6 and Fe2TeO6

The crystal structure and measurement of the thermodynamic quantities of Cr2TeO6 and Fe2TeO6 prepared by the solid state reaction were studied. The crystal structure was derived from X-ray powder diffraction, wh

Room temperature gas sensing of p -type Te O2 nanowires

Tellurium dioxide (Te O2) nanowires with a tetragonal structure have been grown by thermally evaporating tellurium metal at 400 °C in air. The nanowires produced have diameters ranging from 30 to 200 nm and have lengths of several tens of micrometers. Gas sensors were fabricated using the obtained Te O2 nanowires. The sensing behavior to N O2, N H3, and H2 S gases at room temperature showed typical characteristics of a p -type semiconductor. The results demonstrate the potential to develop Te O2 nanowire based gas sensors with low power consumption.

Comparative study of bulk and supported V-Mo-Te-Nb-O mixed metal oxide catalysts for oxidative dehydrogenation of propane to propylene

Bulk V-Nb-O, Mo-Nb-O, Te-Nb-O, and V-Mo-Te-Nb-O mixed metal oxides were synthesized and characterized with Raman spectroscopy, XRD, and BET methods. The catalytic properties of these bulk mixed metal oxides were studied for the oxidative dehydrogenation (

TeO2-WO3 glasses: Infrared, XPS and XANES structural characterizations

Transparent (1-x)TeO2-xWO3 glasses with 0≤x≤0.325 mol were synthesized by the fast quenching technique. Several complementary techniques as infrared, X-ray photoelectron and X-ray absorption spectroscopies were used to approach the s

Synthesis, structure, and characterization of novel two- and three-dimensional vanadates: Ba2.5(VO2) 3(SeO3)4·H2O and La(VO 2)3(TeO6)·3H2O

Two new vanadates, Ba2.5(VO2)3(SeO 3)4·H2O and La(VO2) 3(TeO6)·3H2O, have been synthesized by hydrothermal methods using BaCO3, Ba(OH)2·H 2O, La(NO3)3·6H2O, V 2O5, TeO2, and H2SeO3 as reagents. The structures were determined by single-crystal X-ray diffraction. Ba2.5(VO2)3(SeO3) 4·H2O exhibits a two-dimensional layered structure consisting of VO5 square pyramids and SeO3 polyhedra, whereas La(VO2)3(TeO6)·3H2O has a three-dimensional framework structure composed of VO4 tetrahedra and TeO6 octahedra. Infrared and Raman spectroscopy, UV-vis diffuse reflectance spectroscopy, and thermogravimetric analysis are also presented. Crystal data: Ba2.5(VO2)3-(SeO 3)4·H2O, trigonal, space group P3 (No. 147) with a = b = 12.8279(15) A, c = 7.2631(9) A, V = 1035.1(2) A3, and Z = 2; La(VO2)3(TeO 6)·3H2O, trigonal, space group R3c (No. 161) with a = b = 9.4577(16) A, c = 23.455(7) A, V = 1816.9(7) A3, and Z = 6.

New oxyfluoro-tellurates(IV): MTeO3F (M = FeIII, GaIII and CrIII)

The crystal structures of the new isomorphous compounds iron(III) oxyfluoro-tellurate(IV), FeTeO3F, gallium(III) oxy-fluoro-tellurate(IV), GaTeO3F, and chromium(III) oxyfluoro-tellurate(IV), CrTeO3F, consist of zigzag chains of MO4F2 distorted octa-hedra alternately sharing O-O and F-F edges and connected via TeO3 trigonal pyramids. A full O/F anionic ordering is observed and the electronic lone pair of the TeIV cation is stereochemically active.

TeO2 nanoparticles synthesized by evaporation of tellurium in atmospheric microwave-plasma torch-flame

Tellurium dioxide (TeO2) nanoparticles were synthesized directly by evaporation of tellurium (Te) granules in an atmospheric microwave-plasma torch-flame with possibility for a direct continuous preparation and mass production of TeO2 nanoparticles. The mean size of the synthesized TeO2 particles was 108.2 nm observed from the TEM image and was 112.0 nm estimated by the Williamson-Hall plot using XRD data. The surface area and pore distribution properties of the particles were also analyzed by making use of a nitrogen adsorption apparatus.

Characterization of nanocrystalline bismuth telluride (Bi 2Te3) synthesized by a novel approach through aqueous precursor method

Bi2Te3-based alloys are currently best-known, technologically important thermoelectric materials near room temperature. In this paper, nanocrystalline Bi2Te3 was synthesized by an aqueous solution technique based on the reaction between the aqueous solution of Bi-ethylenediamine tetraaceticacid (EDTA), TeO-EDTA, and NaBH4 at room temperature. NaBH4 was used as a reducing agent. TeO-EDTA was prepared from TeO2 after satisfactory purification. The sample purity was examined by selected area energy dispersive X-ray analysis. The products were characterized by X-ray diffraction and high-resolution transmission electron microscopy by which the particle morphologies and size were studied. The particle size ranges from 60 to 90 nm.

Synthesis and structure determination of In3TeO 3F7: An indium oxyfluorotellurate IV derived from W bronze structure with Te4+ in hexagonal tunnels

After InTeO3F and InTe2O5F recently described, a new compound In3TeO3F7 is characterized in the In-TeIV-O-F system. The crystal structure was determined by single X-ray diffraction and refined to R1 = 0.028. In3TeO3F7 crystallizes in orthorhombic space group Cmmm, a = 7.850(2) , b = 27.637(6) , c = 4.098(1) , V = 889.1(4) 3 and Z = 4. Its structure consists of the stacking, via vertices, of identical layers composed of InF6 and InO2F4 octahedra sharing corners and of InO4F3 pentagonal bipyramids sharing edges and vertices. The Te cations statistically occupy one or the other of two close sites located inside tunnels delimited by the In polyhedra and are bonded to F anions located in the same tunnels. The structure can be considered as an intergrowth of parallel strips of MIn3F 10 and hexagonal tungsten bronze (c)-types. It is compared to other structures such as the bronze Sb0.157WO3, TeMo 5O16 and Sb2Mo10O31, phases also comprising Te4+ or Sb3+ inside hexagonal tunnels. The electronic lone pair of Te4+ is stereochemically active and a perfect O/F ordering occurs on the anionic sites.