Silver telluride

Silver telluride (Ag₂Te) is a chemical compound, a telluride of silver, also known as disilver telluride or silver(I) telluride. It forms a monoclinic crystal. In a wider sense, silver telluride can be used to denote AgTe (silver(II) telluride, a metastable compound) or Ag₅Te₃.

Silver telluride

Names
Other names Hessite
Identifiers
CAS Number	12002-99-2 Y
3D model (JSmol)	Interactive image
ECHA InfoCard	100.031.277
PubChem CID	6914515
CompTox Dashboard (EPA)	DTXSID501045482
InChI InChI=1S/2Ag.Te Key: YRXWPCFZBSHSAU-UHFFFAOYSA-N
SMILES [Ag][Te][Ag]
Properties
Chemical formula	Ag2Te
Molar mass	341.3364 g/mol
Appearance	grey-black crystals
Density	8.318 g/cm3
Melting point	955 °C (1,751 °F; 1,228 K)
Refractive index (nD)	3.4
Structure
Crystal structure	Monoclinic, mP12
Space group	P21/c, No. 14
Except where otherwise noted, data are given for materials in their standard state (at 25 °C [77 °F], 100 kPa). N verify (what is YN ?) Infobox references

Silver(I) telluride occurs naturally as the mineral hessite, whereas silver(II) telluride is known as empressite.

Silver telluride is a semiconductor which can be doped both n-type and p-type. Stoichiometric Ag₂Te has n-type conductivity. On heating silver is lost from the material.

Non-stoichiometric silver telluride has shown extraordinary magnetoresistance.

Synthesis

Porous silver telluride (AgTe) is synthesized by an electrochemical deposition method. The experiment can be performed using a potentiostat and a three-electrode cell with 200 mL of 0.5 M sulfuric acid electrolyte solution containing Ag nanoparticles at room temperature. Then a silver paste used in the tungsten ditelluride (WTe₂) attachment leach into the electrolyte which causes small amounts of Ag to dissolve in the electrolyte. The electrolyte was stirred by a magnetic bar to remove hydrogen bubbles. A silver- silver chloride electrode and a platinum wire can be used as reference and counter electrodes. All the potentials can be measured against the reference electrode, and it was calibrated using the equation ERHE = EAg/AgCl + .059 pH + .197. In order to grow the porous AgTe, the WTe₂ was treated using multiple cyclic voltammetry between -1.2 and 0 volts with a scan rate of 100 mV/s.

Glutathione coated Ag₂Te Nanoparticles can be synthesized by preparing a 9 mL solution containing 10 mM AgNO₃, 5mM Na₂TeO₃, and 30 mM glutathione. Place that solution in an ice bath. N₂H₄ was added to the solution and the reaction is allowed to proceed for 5 min under constant stirring. Then the nanoparticles are washed three times by a way of centrifugation, after the three washes the nanoparticles are suspended in PBS and washed again with that same method.

References

• Aliev, F. F. (2002). "Phase Transition of Ag_Enriched Ag₂Te". Inorganic Materials. 38 (10): 995–997. doi:10.1023/A:1020512918319. S2CID 91815176.
• Chuprakov, I. S.; Dahmen, K. H. (1998). "Large positive magnetoresistance in thin films of silver telluride". Applied Physics Letters. 72 (17): 2165. Bibcode:1998ApPhL..72.2165C. doi:10.1063/1.121309.
• Dalven, Richard (1966). "Fundamental Optical Absorption in β-Silver Telluride". Physical Review Letters. 16 (8): 311. Bibcode:1966PhRvL..16..311D. doi:10.1103/PhysRevLett.16.311.
• Hagyeong Kwon, Dongyeon Bae, Dongyeun Won, Heeju Kim, Gunn Kim, Jiung Cho, Hee Jung Park, Hionsuck Baik, Ah Reum Jeong, Chia-Hsien Lin, Ching-Yu Chiang, Ching-Shun Ku, Heejun Yang, and Suyeon Cho "Nanoporous Silver Telluride for active hydrogen evolution." (n.d.) https://pubs.acs.org/doi/10.1021/acsnano.0c09517

See also

• Hessite
• Empressite
• Sylvanite

Related materials

• Silver selenide
• Silver sulfide