Thiosulfate electrodeposition

Generally, the experimental results on electrodeposition of CdS in acidic solutions of thiosulfate have implied that CdS growth does not involve underpotential deposition of the less noble element (Cd), as would be required by the theoretical treatments of compound semiconductor electrodeposition. Hence, a fundamental difference exists between CdS and the other two cadmium chalcogenides, CdSe and CdTe, for which the UPD model has been fairly successful. Besides, in the present case, colloidal sulfur is generated in the bulk of solution, giving rise to homogeneous precipitation of CdS in the vessel, so that it is quite difficult to obtain a film with an ordered structure. The same is true for the common chemical bath CdS deposition methods. 

Single-phase ZnS films of a fine grain size (no XRD shown) and a band gap of 3.7 eV were electrodeposited from aqueous alkaline (pH 8-10) solutions of zinc complexed with EDTA, and thiosulfate as a sulfur source [101]. The voltammet-ric data implied that deposition occurred either by S-induced UPD of Zn or by a pathway involving both Zn " and thiosulfate concurrently. 

Attempts to electrodeposit M0S2 in a way similar to that used for MoSe2 - in this case from solutions of molybdate and thiosulfate under various conditions of pH and temperature - have been unsuccessful. Instead, thin films of M0S2 were convenienfly deposited from tetrathiomolybdate solutions Ponomarev et al. [149] observed that reduction of MoO in slightly alkaline solutions results in the formation of an X-ray amorphous film which by annealing at 550 in Ar for 1 h... 

Recendy, ID quantum dots of gallium selenide with average diameter 8-10 nm, connected in the form of chains of average length 50-60 nm, were synthesized on rro substrates by cathodic electrodeposition from acidic aqueous solutions of gallium(III) nitrate and selenious acid [186], The structural analysis from XRD patterns revealed the formation of Ga2Se3/GaSe composition. The films were found to be photoactive in aqueous sodium thiosulfate solution and showed p-type conductivity. 

Vandeputte et al. [122] used both of these equations to derive more accurate values of the constants than could be obtained from the Koutecky-Levich analysis alone, and hence derived rate constants for the predissociation of the thiosulfate complex involved in the electrodeposition of silver from thiosulfate solutions. 

Iodide in solution was determined by means of a piezoelectric crystal with silver electrodes connected to a normal TTL oscillator (104). In a follow-up- study (105), iodide was determined in the range 0.5 - 7 jM by electrodeposition on the silver electrodes of a crystal. Thiosulfate, cyanide, sulfide, Fe(III), Hg(II), and Ag interfered, but procedures to eliminate their interferences were described. 

Alonso Alejandro R, Lapidus Gretchen T, Gonzalez I (2007) A strategy to determine the potential interval for selective silver electrodeposition from ammonia-cal thiosulfate solutions. Hydrometallurgy 85 144-153. doi 10.1016/j.hydromet.2006.08.009... 

From Acidic Aqueous Solutions Acidic aqueous solutions used for the cathodic electrodeposition of CdS semiconductors usually contain Cd and 8203 (thiosulfate) ions as the sources of Cd and S, respectively [13-17]. Sometimes, complexing agents such as EDTA are used to coordinate Cd " ions [14]. Gelatin has been added to stabilize small sulfur particles (colloidal sulfur in the form of Sg) to provide better conditions for the electrodeposition [16]. According to Denisson [18], two overall processes explain the formation of CdS by electrodeposition ... 

Zar bska K, Skompska M (2011) Electrodeposition of CdS from acidic aqueous thiosulfate solution— invesitigationof the mechanism by electrochemical quartz microbalance technique. Electrochim Acta 56 5731... 

Mixed Sulfite-Thiosulfate Bath for Soft Gold Electrodeposition (Concentration in mol h unless Otherwise Noted)... 

Electrodeposition of soft gold from a thiosulfate-sulfite bath for electronics application, T. Osaka, A. Kodera,... 

Mechanism of sulfur inclusion in soft gold electrodeposited from the thiosulfate-sulfite bath, T. Osaka, M. Kato, J. Sato, K. Yoshizawa, T. Homma, Y. Okinaka, and O. Yoshioka, J. Electrochem. Soc., 2001, 148, C659. 

Electrodeposition of gold from a thiosulfate-sulfite bath for microlectronic apphcations, T. A. Green, M.-J. Liew, and S. Roy, J. Electrochem. Soc., 2003, 150, C104. 

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