Fig. 5: Analytical performance and stability of the sensor.
a SWV response spectra of the BSA/Bi2OW6/g-C3N4/GA coating electrode with the best ratio optimization to four heavy metal concentrations of 10 μg/L under different pH conditions. b SWV response spectra of the BSA/Bi2OW6/g-C3N4/GA coating electrode with the best ratio optimization at different deposition potentials to four heavy metal concentrations of 10 μg/L. c Performance stability of the same electrode for four heavy metal ions at fixed concentrations of 5 μg/L each under long-term use conditions. d The concentrations of Cd²⁺, Pb²⁺, Hg²⁺, and Zn²⁺ were systematically and synchronously varied from 0.05 to 10 μg/L. e The figure shows the current response extracted from d and the corresponding data of the four heavy metal concentration changes and the linear fit. Five experiments were averaged using five independent electrodes. The dots represent the mean of the current, and the error bars are the standard deviation of the mean. f Stability performance test of different electrodes via multiple current responses to four heavy metal ions, tested five times at a fixed concentration of 5 μg/L.
