Article Dans Une Revue Electrochemistry Communications Année : 2007

Electrochemical quartz crystal microbalance determination of nickel formal partial charge number during nickel-underpotential deposition on platinum in sulphate media

Résumé

We studied nickel-underpotential deposition (UPD) on polycrystalline platinum in sodium sulphate media using Electrochemical Quartz Crystal Microbalance (EQCM). EQCM enables to separate hydrogen and nickel adsorption/desorption contributions, which was impossible solely with electrochemistry. Thus, nickel coverage can be determined: nearly 0.8 NiUPD monolayer over platinum is deposited above nickel Nernst potential for pH 5.5. Coupling the gravimetric signal with nickel stripping peak coulometry yields the nickel formal partial charge number: ιNi,EQCM = 1.3 ± 0.13. Electrochemical measurements using Swathirajan and Bruckenstein’s method give: ιNi = 1.5 ± 0.17. Within the errors bars, both methods give similar results and ιNi lower than zNi2+: nickel adatoms apparently remain partially charged upon UPD on platinum following anion and nickel co-adsorption.

Dates et versions

hal-00333724 , version 1 (23-10-2008)

Identifiants

Citer

Marian Chatenet, Yvonne Soldo-Olivier, Eric Chaînet, René Faure. Electrochemical quartz crystal microbalance determination of nickel formal partial charge number during nickel-underpotential deposition on platinum in sulphate media. Electrochemistry Communications, 2007, 9 (7), pp. 1463-1468. ⟨10.1016/j.elecom.2007.02.001⟩. ⟨hal-00333724⟩
134 Consultations
0 Téléchargements

Altmetric

Partager

  • More