Stripping voltammetric measurements were performed with an
in situ deposition of the bismuth film and NT ions in the presence of
dissolved oxygen. Studies were carried out by dropping a 100L of
the sample solution in the well. A deposition potential of −1.2V
vs. Ag/AgCl was applied to the carbon working electrode without
stirring the solution. After deposition, the voltammogram was
recorded by applying a positive-going square-wave voltammetric
potential scan (with a frequency of 20 Hz, amplitude of 25 mV, and
potential step of 5mV). The scan was from −1.2V to 0.0V (Wang
et al., 2000). Based on our previous optimization studies, 1mg/L of
bismuth and 10 min of deposition time were used for all SWASV
measurements. All experiments were carried out at room temperature.
Every measurement was replicated three times. All curves
were the average of three test results.