Simultaneous Electrochemical Detection of Cd²⁺ and Pb²⁺ Based on an MOF-Derived Carbon Composite Linked with Multiwalled Carbon Nanotubes

Abstract

Heavy metal ion (HMI) pollution is a serious threat to human health and the ecosystem. Therefore, there is an urgent need to develop a fast and sensitive platform for heavy metal ion detection. In this work, a novel sensing platform based on ZIF-67-derived cobalt/nitrogen-doped carbon (NC) composite polyhedrons linked with multiwalled carbon nanotubes (MWCNTs), termed Co@NC/MWCNT, for the simultaneous monitoring of Cd2+ and Pb2+ was established. In detail, nanoporous ZIF-67 was first in situ grown on the MWCNTs, followed by carbonization, endowing the composite with good electrical conductivity and a large specific surface area, providing more active sites for subsequent metal ion attachment. Under optimal parameters, the proposed sensing platform exhibited a relatively wider linear range of 0.12–2.5 μM, with lower limits of detection (LODs) of 4.5 nM (Cd2+) and 4.9 nM (Pb2+). Notably, it was worth mentioning that the linearity of the as-prepared sensing platform in the actual water sample was highly consistent with the linearity in the buffer solution, showing outstanding anti-interference performance. Finally, the designed sensing platform performed well in several kinds of natural water environment when compared with the standard method, demonstrating huge potential in trace HMI monitoring.

Simultaneous and sensitive detection of dopamine and acetaminophen at a glassy carbon electrode modified with a carbonized-ZIF-67/Super P nanocomposite

“…In addition, at 787.3 and 803.0 eV are the satellite peaks of both of them. The same result was obtained as other reports, 42,43 proving that C-ZIF-67/SP was successfully prepared.…”

Amino-Functionalized Hierarchical Porous Carbon Derived from Zeolitic Imidazolate Frameworks for Ultrasensitive Electrochemical Sensing of Heavy Metals in Water

“…Consistently, the response signals increase rapidly while the deposition time increased from 30 to 180 s (Figure S10b). However, the stripping currents reach a plateau when the deposition time is further increased, probably due to the saturation of HMI adsorption sites . Thus, a deposition time of 180 s is selected in the following experiments.…”

“…However, the stripping currents reach a plateau when the deposition time is further increased, probably due to the saturation of HMI adsorption sites. 55 Thus, a deposition time of 180 s is selected in the following experiments. The effect of solution pH on E(6)-C-HP-ZIF-8 sensing performance is presented in Figure S10c in the SI.…”

Hydrophobic polymer nano hybrid ternary composite electrode for nanomolar tracing of Cd2+ ions

“…However, it has also brought about a range of environmental issues causing a significant threat to human health. [1][2][3][4][5] Among these issues, there is an increasing concern about water pollution, largely attributed to the existence of heavy metal ions (HMIs). [6][7][8][9][10][11] HMIs like Cd 2+ , Hg 2+ , Cr 2+ , and Pb 2+ are hard pollutants that resist biodegradation and tend to accumulate in organisms through ecological chains.…”

“…The rapid expansion of industrial demand has contributed to economic progress. However, it has also brought about a range of environmental issues causing a significant threat to human health 1–5 . Among these issues, there is an increasing concern about water pollution, largely attributed to the existence of heavy metal ions (HMIs) 6–11 .…”