Cyanide ion-selective electrodes based on thin electroplated membranes of silver chalcogenides: Part I. Membrane preparation and characterization

✍ Scribed by M.T. Neshkova; E.M. Pancheva

• Publisher: Elsevier Science
• Year: 1991
• Tongue: English
• Weight: 856 KB
• Volume: 242
• Category: Article
• ISSN: 0003-2670
• DOI: 10.1016/0003-2670(91)87049-d

✦ Synopsis

Cyanide-responsive ion-selective electrodes have been developed based on thin tellurium-doped silver selenide membranes electrodeposited on platinum substrates . The chemical composition of the electroplated film membranes could be expressed by the general formula Age+ 1$e1 _ xTex (where 0 .2 < S < 0 .8 and 0.2 >_ x > 0.1). These electrodes exhibit a linear response in cyanide solutions with concentrations ranging from 10 -2 to 10 -6 M, with a slope of the electrode function of about 90 mV (pCN) -1 (i .e., lower than the theoretically predicted double-Nernstian slope) . These electrodes showed very stable behaviour during long-term investigation (several months) . The conditions for the electrochemical preparation of cyanide-responsive silver chalcogenide membranes are discussed both from theoretical and practical points of view . X-ray diffraction, energy-dispersive x-ray fluorescence microanalysis (EDAX) and scanning electron microscopy (SEM) were used to examine the membrane composition, structure and surface morphology.