Sn-Pb Hybrid Nanoparticle Decorated Mesoporous Carbon for Sensitive Stripping Detection of Cd (II)

Novel Sn-Pb hybrid nanoparticle decorated mesoporous carbon (MPC) was successfully prepared on a glassy carbon electrode (GCE) and used for the anodic stripping measurements of Cd(II) via square wave Voltammetry. In the presence of MPC, the properties of Sn-Pb were dramatically improved including the ability of electron transfer, particle size and hydrophilicity, which played a significant role in achieving more preferable analytical performances of Cd(II) with Sn-Pb based sensor. After all the experimental parameters involved were carefully optimized, the proposed Sn-Pb/MPC based sensor was applied to the stripping determination of Cd(II), showing the best electrochemical behaviors by comparison with Sn, Pb and Sn-Pb modified electrodes. The synergic effect between Sn-Pb and MPC was believed to be the major factor leading to such improved electrochemical properties of Sn-Pb/MPC based sensor for Cd(II) analysis. In the concentration range of 0–140 μg L−1, the linear analytical curve for Cd(II) was achieved with correlation coefficient and detection limit calculated to be 0.9996 and 0.36 μg L−1 (S/N = 3), respectively. By using the standard addition method, Cd(II) ion in river samples was successfully determined with satisfactory recoveries higher than 100%. These results suggest that the proposed method can be applied as a simple, efficient alternative to monitor the heavy metals in water samples, compared with ICP based techniques.