Combination of Microporous Hollow Carbon Spheres and Nafion for the Individual Metal-free Stripping Detection of Pb(2+) and Cd(2.).
Here, the combination of Nafion with microporous hollow carbon spheres (MHCS) is first proposed to fabricate a disposable metal-free electrode for heavy metal stripping sensing. The MHCS-Nafion composite film electrode is prepared by drop-casting a mixture of MHCS and Nafion onto the lab-made screen-printed carbon electrode (SPCE(*)). Results demonstrate that the interfusion of MHCS into Nafion offers enhanced performance for the electro-enrichment and stripping of lead and cadmium over the only Nafion film: 1) abundant MHCS immobilized on the electrode surface serve as effective nucleation sites for metal ion reduction; 2) the mixing of MHCS into Nafion enlarges the active surface of negative-charged Nafion for the electrostatic adsorption of metal cations. The proposed MHCS-Nafion/SPCE(*) provides linear responses for Pb(2+) and Cd(2+) in the range of 2 - 200 μg/L, with a detection limit of 1.37 and 1.63 μg/L, respectively. Practical applications of the sensor in water sample detection with good accuracy have also been confirmed.
Shanghai Key Laboratory of Functional Materials Chemistry, East China University of Science and Technology.
Xiangheng
X
Niu
Hongwei
H
Zhang
Meihua
M
Yu
Hongli
H
Zhao
Minbo
M
Lan
Chengzhong
C
Yu