7783-09-7

Basic information

• Product Name: Hydrogen telluride
• Synonyms: Hydrogen telluride;Dihydridetellurium;Dihydrotellurium;Tellurium hydride;TeH2;Einecs 231-981-5
• CAS NO: 7783-09-7
• Molecular Formula: H2Te
• Molecular Weight: 129.61588
• EINECS: 231-981-5
• Mol File: 7783-09-7.mol
• Article Data: 29

Chemical Properties

• Melting Point: -49°
• Boiling Point: bp -2°
• Appearance: /colorless gas
• Density: dliq-12 2.68
• Water Solubility: soluble H2O, unstable solution; soluble alcohol and alkalies [HAW93]
• CAS DataBase Reference: Hydrogen telluride(CAS DataBase Reference)
• NIST Chemistry Reference: Hydrogen telluride(7783-09-7)
• EPA Substance Registry System: Hydrogen telluride(7783-09-7)

Safety Data

• Hazardous Substances Data: 7783-09-7(Hazardous Substances Data)

Usage

Description

Hydrogen telluride has the formula, H2Te. The simplest hydride of Te, it is rarely encountered because of its tendency to decompose to the constituent elements. Most compounds with Te–H bonds are unstable with respect to loss of H2. H2Te is chemically and structurally similar to H2S, and both are acidic species with H–X–H angles approaching 90°.The tellurides of the alkaline earth metals tend to immediately decompose on exposure to air, with liberation of tellurium. H2Te is prepared by the acidification of salts of Te2-,such as Al2Te3 and Na2Te. Na2Te can be generated by the reaction of Na and Te in anhydrous ammonia. The intermediate in the acidification, the HTe is a stable anion. H2Te is an endothermic compound, and is unstable in air, rapidly decomposing into water and elemental tellurium: 2H2Te+ O2 → 2H2O+ 2Te It is almost as acidic as phosphoric acid (pKa=8.1×10-3), having a pKa value of about 2.3×10-3. It reacts with many metals to form tellurides. However, many of these are unstable relative to their decomposition to the elements. Its CAS number is 7783-09-7 and its molecular weight is 129.6158 g/mol. It is a colorless gas and is toxic if breathed. Its density is 3.310 g/cm3 and its melting point is –49°C with a boiling point of –2.2°C. Its solubility in water is 0.701 g/100 ml of water at 20°C.

Chemical Properties

Colorless gas.Soluble in water but unstable; soluble in alcohol and alkalies.

Physical properties

Colorless gas; strong garlic-like odor; stable to light when dry but under-goes photochemical decompostion in the presence of moisture and dust; den-sity 5.68 g/L; liquefies to a colorless unstable liquid at -2°C, decomposed bylight; liquid density 2.57 g/mL at -20°C; solidifies at -49°C; soluble in water,alcohol and alkalies; pKa 2.6 (for first dissociation constant at 18°C) and 11.0(the dissociation constant at 25°C) for the second replaceable hydrogen.

Uses

It is synthesized by the action of acid on aluminum telluride. It has no industrial uses.

Preparation

Hydrogen telluride is prepared by the reaction of aluminum telluride,Al2Te3 with hydrochloric acid: Al2Te3 + 6HCl → 3H2Te + 2AlCl3 It also may be prepared by electrolysis of a 50% sulfuric acid solution using atellurium cathode.

Hazard

See hydrogen selenide.

InChI:InChI=1S/H2Te/h1H2

Upstream product

• 14683-12-6 tellurium 
• 7440-38-2 arsenic 
• 7803-52-3 stibane 
• 7732-18-5 water 
• 7664-93-9 sulfuric acid 
• 14683-12-6 tellurium^(2-) 
• 1333-74-0 hydrogen 
• 7553-56-2 iodine 
• 7782-41-4 fluorine 
• 7782-50-5 chlorine 
• 13494-80-9 hydrogen telluride 
• 16940-66-2 sodium tetrahydroborate 
• 7647-01-0 hydrogenchloride 

Downstream Products

• 12142-40-4 dipotassium telluride 

Relevant articles and documents

NiTe2 Nanowire Outperforms Pt/C in High-Rate Hydrogen Evolution at Extreme pH Conditions

Better hydrogen generation with nonprecious electrocatalysts over Pt is highly anticipated in water splitting. Such an outperforming nonprecious electrocatalyst, nickel telluride (NiTe2), has been fabricated on Ni foam for electrocatalytic hydrogen evolution in extreme pH conditions, viz., 0 and 14. The morphological outcome of the fabricated NiTe2 was directed by the choice of the Te precursor. Nanoflakes (NFs) were obtained when NaHTe was used, and nanowires (NWs) were obtained when Te metal powder with hydrazine hydrate was used. Both NiTe2 NWs and NiTe2 NFs were comparatively screened for hydrogen evolution reaction (HER) in extreme pH conditions, viz., 0 and 14. NiTe2 NWs delivered current densities of 10, 100, and 500 mA cm-2 at the overpotentials of 125 ± 10, 195 ± 4, and 275 ± 7 mV in 0.5 M H2SO4. Similarly, in 1 M KOH, overpotentials of 113 ± 5, 247 ± 5, and 436 ± 8 mV were required for the same current densities, respectively. On the other hand, NiTe2 NFs showed relatively poorer HER activity than NiTe2 NWs, which required overpotentials of 193 ± 7, 289 ± 5, and 494 ± 8 mV in 0.5 M H2SO4 for the current densities of 10 and 100 mA cm-2 and 157 ± 5 and 335 ± 6 mV in 1 M KOH for the current densities of 10 and 100 mA cm-2, respectively. Notably, NiTe2 NWs outperformed the state-of-the-art Pt/C 20 wt % loaded Ni foam electrode of comparable mass loading. The Pt/C 20 wt % loaded Ni foam electrode reached 500 mA cm-2 at 332 ± 5 mV, whereas NiTe2 NWs drove the same current density with 57 mV less. These encouraging findings emphasize that a NiTe2 NW could be an alternative to noble and expensive Pt as a nonprecious and high-performance HER electrode for proton-exchange membrane and alkaline water electrolyzers.

Self-organization of plasmonic and excitonic nanoparticles into resonant chiral supraparticle assemblies

Chiral nanostructures exhibit strong coupling to the spin angular momentum of incident photons. The integration of metal nanostructures with semiconductor nanoparticles (NPs) to form hybrid plasmon-exciton nanoscale assemblies can potentially lead to plasmon-induced optical activity and unusual chiroptical properties of plasmon-exciton states. Here we investigate such effects in supraparticles (SPs) spontaneously formed from gold nanorods (NRs) and chiral CdTe NPs. The geometry of this new type of self-limited nanoscale superstructures depends on the molar ratio between NRs and NPs. NR dimers surrounded by CdTe NPs were obtained for the ratio NR/NP = 1:15, whereas increasing the NP content to a ratio of NR/NP = 1:180 leads to single NRs in a shell of NPs. The SPs based on NR dimers exhibit strong optical rotatory activity associated in large part with their twisted scissor-like geometry. The preference for a specific nanoscale enantiomer is attributed to the chiral interactions between CdTe NP in the shell. The SPs based on single NRs also yield surprising chiroptical activity at the frequency of the longitudinal mode of NRs. Numerical simulations reveal that the origin of this chiroptical band is the cross talk between the longitudinal and the transverse plasmon modes, which makes both of them coupled with the NP excitonic state. The chiral SP NR-NP assemblies combine the optical properties of excitons and plasmons that are essential for chiral sensing, chiroptical memory, and chiral catalysis.

X-ray luminescence of CdTe quantum dots in LaF3:Ce/CdTe nanocomposites

CdTe quantum dots have intense photoluminescence but exhibit almost no x-ray luminescence. However, intense x-ray luminescence from CdTe quantum dots is observed in LaF3:Ce/CdTe nanocomposites. This enhancement in the x-ray luminescence of CdTe quantum dots is attributed to the energy transfer from LaF3:Ce to CdTe quantum dots in the nanocomposites. The combination of LaF3:Ce nanoparticles and CdTe quantum dots makes LaF3:Ce/CdTe nanocomposites promising scintillators for radiation detection.