Underpotential deposition of tin(II) on a gold disc electrode and determination of tin in a tin plate sample.
This work describes a study of the underpotential deposition (UPD) of Sn2+ on a polycrystalline gold disc electrode using cyclic voltammetry (CV) and chronocoulometry (CC). Sn2+ ions showed well-defined peaks from UPD and UPD stripping (UPD-S) in 1 mol/L HCl solutions, while bulk deposition (BD) and BD stripping (BD-S) of the ions were also observed. The measured UPD shifts, DeltaE(UPD), between the UPD-S and the BD-S peaks were more than 200 mV. The UPD charge and the surface coverage of tin were measured by CC. A new method for determining Sn2+ was therefore developed, based on the excellent electrochemical properties of the Au/Sn UPD system. A plot of the UPD-DPASV (differential pulse anodic stripping voltammetry) signal versus the Sn(II) concentration was obtained for [Sn(II)] of 1.98x10(-7) to 3.64x10(-5) M. The method developed here has been applied to determine the tin in a tin plate sample.
Qiao
Zhiqing
Z
Department of Chemistry, Lanzhou University, Lanzhou, 730000, People's Republic of China.
Shang
Wei
W
Zhang
Xin
X
Wang
Chunming
C