Author(s)

Huy Du Nguyen¹, T. Thuy Luyen Nguyen¹, Khac Manh Nguyen¹, T. Anh Tuyet Tran¹, Anh Mai Nguyen¹, Quoc Hien Nguyen^2*

¹Central Laboratory for Analysis, University of Science, Vietnam National University in Ho Chi Minh City, Ho Chi Minh City, Vietnam.
²Research and Development Center for Radiation Technology, Vietnam Atomic Energy Institute, Ho Chi Minh City, Vietnam.

The nano-gold layer formed on the platinum rotating disk electrode (nano-Au/Pt-RD) inherited the catalytic property for Cr(VI) reduction from platinum surface and owned the good features of nano-gold such as insensitivity with hydrogen ion, high surface area, augmenting diffusion of Cr(VI) and ability for self-assembling with 4-pyridine-ethanethiol (PET) through Au←S linkages, to form PET/nano-Au/Pt-RD electrode capable of accumulating Cr(VI) from sample. The obtained PET/ nano-Au/Pt-RD electrode showed an extreme sensitivity to Cr(VI). By using this electrode, 1.09 ng·L^﹣1 was the detection limit of differential pulse adsorptive cathodic stripping voltammetry for Cr(VI) with the accumulation time of only 2 min. Moreover, this electrode was reproducible with 3.5% RSD for 30 times of Cr(VI) accumulating and stripping. In addition, this electrode was also selective for Cr(VI) determination, which was not almost interfered by other inorganic ions.

Nano-Gold Layer, Platinum Electrode, Stripping Voltammetry

Nguyen, H. , Nguyen, T. , Nguyen, K. , Tran, T. , Nguyen, A. and Nguyen, Q. (2015) Determination of ppt Level Chromium(VI) Using the Gold Nano-Flakes Electrodeposited on Platinum Rotating Disk Electrode and Modified with 4-Thiopyridinium. American Journal of Analytical Chemistry, 6, 457-467. doi: 10.4236/ajac.2015.65045.