title: A cation trap for anodic stripping voltammetry: NH3-plasma treated carbon nanotubes for adsorption and detection of metal ions.
abstract: NH(3)-plasma treated multi-walled carbon nanotubes (pn-MWCNTs) with cation traps for the detection of ultratrace quantities of Zn(II), Cd(II), Cu(II), and Hg(II) using square wave anodic stripping voltammetry (SWASV) is described. The pn-MWCNTs use their adsorption performance to enhance the sensitivity. It is found that under optimized conditions Zn(II), Cd(II), Cu(II) and Hg(II) were individually detected at potentials of -1.16, -0.78, -0.268 and 0.108 V, respectively. The detection limit (3σ method) of 0.314, 0.0272, 0.2263, and 0.1439 nM toward Zn(II), Cd(II), Cu(II), and Hg(II) is achievable, respectively. No interference could be seen during the simultaneous detection of Zn(II), Cd(II), Cu(II), and Hg(II). The pn-MWCNTs exhibit excellent selectivity owing to the different ability of adsorption. A study of the ability of pn-MWCNTs in practical application is carried out using a sample of water collected from Dongpu Reservoir in Hefei City, Anhui, China. It is found that the results were favorable when compared against inductively coupled plasma atomic emission spectrometry (ICP-AES) analysis.
authors.affiliation: Department of Chemistry, Wannan Medical College, Wuhu 241002, PR China.
authors.forename: Yan
authors.initials: Y
authors.lastname: Wei
authors.forename: Ran
authors.initials: R
authors.lastname: Yang
authors.forename: Xing
authors.initials: X
authors.lastname: Chen
authors.forename: Lun
authors.initials: L
authors.lastname: Wang
authors.forename: Jin-Huai
authors.initials: JH
authors.lastname: Liu
authors.forename: Xing-Jiu
authors.initials: XJ
authors.lastname: Huang
mesh_terms: D000327:Adsorption; D000641:Ammonia / Q000032:analysis*; D002412:Cations; D004563:Electrochemistry; D005618:Fresh Water / Q000737:chemistry; D007477:Ions; D057230:Limit of Detection; D019216:Metals, Heavy / Q000737:chemistry*; D008958:Models, Molecular; D037742:Nanotubes, Carbon / Q000737:chemistry*; D014131:Trace Elements / Q000032:analysis*
chemical_list: D002412:Cations; D007477:Ions; D019216:Metals, Heavy; D037742:Nanotubes, Carbon; D014131:Trace Elements; D000641:Ammonia