Fabrication and Electrochemical Behavior Investigation of a Polypyrrole/4-Hydroxy-6-methyl-2-mercaptopyrimidine Comodified Gold Electrode.
A polypyrrole (PPy)/4-hydroxy-6-methyl-2-mercaptopyrimidine (HMMP) comodified gold electrode was prepared and characterized in the form of PPy/HMMP/Au. The polymerization mechanisms of pyrrole on a bare Au electrode, a dodecanethiol-modified gold electrode, and a HMMP/Au electrode are compared and discussed. With ascorbic acid as a probe, various factors affecting the electrochemical characteristics of the PPy/HMMP/Au electrode are investigated. The catalytic activity for the electrochemical oxidation of l-ascorbic acid was studied in 0.1 mol. L-1 NaCl and 1.0 x 10(-3) mol. L-1 HCl. Both the kinetics of oxidation and the reproducibility of the electrochemical response are enhanced at the comodified electrode compared to that of an unmodified metal electrode or the PPy/Au electrode in determination of ascorbic acid. Copyright 1999 Academic Press.
Chen
M
Department of Chemistry, Lanzhou University, Lanzhou, 730000, China
Nie
MY
Li
HL