Characterization and electrocatalytic application of silver modified polypyrrole electrodes

Abstract

Silvermodified polypyrrole electrodes were prepared with the aim of testing them for the electro oxidation of formaldehyde in alkaline solution. The modification of polypyrrole by immersion in aqueous AgNO3 solution was studied by cyclic voltammeter and vacuum techniques (AES and XPS). The influence of time of immersion and the thickness of the polypyrrole film, prepared by electrochemical polymerization, on the modification of the polymer were examined. The results acquired from both electrochemical and spectroscopic examinations show that immersion of a polypyrrole electrode in a AgNO3 solution results in its modification with silver, which is deposited in the elemental state on the surface. The quantity of silver deposited depends not only on the immersion time but also on the thickness of the polymer film. A modified PPy/Ag electrode exhibits catalytic activity for the electro oxidation of CH2O in NaOH. In spite of the low quantity of silver, the activity of the electrode for this reaction is comparable to that of a polycrystalline silver electrode.

Characterization of a Silver Modified PVCAc Electrode and Its Application as a Ag(I)‐Selective Potentiometric Sensor

“…Also, bare GC was immersed in 0.01 M AgNO 3 solution during the same time as when coated with PVC membrane, but the response to Ag + this time was far from Nernstian. Thus, it was concluded that the polymeric membrane retained its response to silver ions and bearing in mind our earlier results 14, 15 we assumed that the PVCAc membrane was modified by silver.…”

“…As can be seen this electrode has the best response to the silver cation, better than to other species. We showed earlier that GC as well as polypyrrole (PPy) could be modified by silver simply by immersion of the electrode in silver nitrate solution 14, 15. So, in order to distinguish whether the response of PVC membrane to silver ions was due to membrane modification or possibly from the modified GC support, the comparable membrane of the same composition was coated on Pt wire.…”

Electroconducting materials based on polypyrrole

“…[57][58][59]. Usually used substrates for polymer deposition are electrodes made of graphite, carbon fibers, glassy carbon, Indium-tin oxide (ITO), inert metals like Au and Pt [11,43,[60][61][62][63][64][65].…”

Metallic‐Based Nanocomposites of Conductive Polymers

“…Most of the studies in this field concern the deposition of noble metals Au [16,[210][211][212][213][214][215][216][217][218][219][220][221][222], Ag [223][224][225][226][227][228][229][230][231][232][233][234][235], Pd [156,158,[236][237][238][239][240][241][242][243][244][245][246][247][248], Pt [249,250] and Hg [251,252], with equilibrium potentials that are positive enough with respect to the potentials of oxidation transitions in most CPs, e.g. PANI, PPY etc.…”