Silver chalcogenides

The kinetics and mechanism of the growth of anodic silver sulfide films on silver metal in aqueous sulfide solutions has been studied under potentiodynamic conditions [162], The Ag2S film formation was presumed to proceed as 

The redox behavior in the silver-selenium-water system at ambient and higher (85 °C) temperatures was studied by Petrov and Belen kii [163]. According to their voltammetry results, and the presented Pourbaix diagram (Fig. 3.9), the stability 

The electrodeposition of tellurium and silver has been investigated in dilute aqueous solutions of tellurous acid and Ag ions (concentrations in the order of 10 to 10 M) in 0.1 M HCIO4 [164], In particular, cyclic voltammetry experiments were conducted with rotating glassy carbon disk electrodes in baths with various concentration ratios of Ag(I) and Te(IV) precursors, and their outcome was discussed in terms of the voltammetric features. For a Ag(I)/Te(IV) ratio close to 0.8, formation of quasi pure silver telluride, Ag2Te, was reported. The authors, based on their measurements and on account of thermodynamic predictions, assumed that silver is deposited first on the electrode (Ag + e Ag), and then Te(IV) is reduced on the previous silver deposit with formation of Ag2Te according to the reaction 

They concluded, thereby, that Ag2Te formation is governed by the initial amount of silver deposit. It is worth noting that the present method, involving dilute electrolytic baths of the compound precursors, deviates from the typical, initially proposed by Panicker et al., method of employing high concentration ratios of the metal to the chalcogen precursor. 

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Some MIECs exhibit metallic properties. These materials can have different concentration of the mobife ioiflc species, compared with that of electrons and holes. Silver chalcogenides, Ag2+sX (X = S, Se, or Te) is an example of a metallic MIEC that conduct electrons and silver ions. These materials are good electronic conductors (close to metallic) and show interesting electronic behavior as a function of temperature as... 

CsFeo.72Agi.28Te2,1053 and Cs2Ag2ZrTe4. The latter has a structure that comprises 2D slabs of Ag- and Zr-centered tetrahedral separated by Cs+ cations.1054 Gas-phase silver chalcogenide ions of the type [Ag2 i E ] (E = S, Se, Te) with < 14 have been investigated by laser-ablation Fourier transform ion cyclotron resonance mass spectrometry.1055... 

DUT/TIS] Dutchak, Y. I., Tishchenko, I. A., Korenchuk, N., Mass-spectrometric investigation of the vapor pressure above solid and liquid silver chalcogenides, Inorg. Mater., 13, (1977), 1586-1588. Cited on pages 299, 300, 547. 

M. Liu and P. Guyot-Sioimest, Preparation and optical properties of silver chalcogenide coated gold nanorods. Journal of Materials Chemistry, 16(40), 3942-3945 (2006). 

To date, a number of MIECs have been reported. Silver chalcogenides, such as Ag2S and Ag2Se, are typical MIECs with a strong research history dating back well over 70 years now [2-5]. In this material, silver cations (Ag" ) and electronic carriers (electron, holes) can... 

BAND STRUCTURE OF SOLID SOLUTIONS OF COPPER AND SILVER CHALCOGENIDES... 

Particular interest in the study of copper and silver chalcogenides is determined by the fact that in these systems cations exhibit abnormally high mobility. A number of studies attempt to explain the emeigence of highly mobile cations by the stmctural features of the band, and the hybridization degree of the d-levels of the metal and p-levels of chalcogen in... 

Superionic Phase Transition Optimizing Thermoelectric Performance in Silver Chalcogenide Nanocrystals... 

Herein, nearly monodisperse silver chalcogenide quantum dots were successfully synthesized through a facile colloidal method, and their thermoelectric... 

Inspired by the above stmctural and electronic band stmcture analysis, we selected silver chalcogenides as examples for the investigation of phase transition with remarkable electronic property change on their thermoelectric property. Monodisperse silver chalcogenides nanocrystals with narrow size distribution were... 

Compared to the binary silver chalcogenide compounds, the phase transition temperature of monodisperse alloyed ternary silver chalcogenide Ag4SeS... 

Kobayashi, M. (1990). Review on structural and dynamical properties of silver chalcogenides. Solid State Ionics, 39, 121—149. 

Xiao, C., Xu, J., Li, K., Feng, J., Yang, J. L., Xie, Y. (2012). Superionic phase transition in silver chalcogenide nanocrystals realizing optimized thermoelectric performance. Journal of the American Chemical Society, 134, 4287-4293. 

The organic surfactants were removed via the procedure of previously reports [2] before fabrication of bulk samples for thermoelectric measurement. Briefly, as-prepared silver chalcogenides were dispersed in cyclohexane with hydrazine solution (85 % v/v) and stirred vigorously until all the nanocrystals precipitated. The supernatant is decanted and the precipitate is washed with ethanol three to four times to remove hydrazine and collected by centrifugation, and then dried in vacuum at 65 °C. After the hydrazine treatment, the nanocrystals are hot-pressed into rectangular (10 mm x 4 mm x 1.5 mm) and round disk bulk samples (with diameter of about 13 mm and thickness of 2 mm) under 60 MPa at 400 for 30 min. 

Chong Xiao, Jie Xu, Kun Li, Jun Feng, Jinlong Yang, and Yi Xie (2012) Superionic Phase Transition in Silver Chalcogenide Nanocrystals Realizing Optimized Thermoelectric Performance. J. Am. Chem. Soc. 134 4287 293... 

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