Dual-nanomaterial based electrode for voltammetric stripping of trace Fe(II) in coastal waters

Abstract

a b s t r a c tIn this work, a dual-nanomaterial based electrode was established for selective and sensitive detection of trace Fe(II) in the presence of complexing agent (2,2′-bipyridyl). Titanium carbide nanoparticles (TiCNPs) were used as the growth-template for the formation of three-dimensional platinum nanoflowers (PtNFs) due to their unique cubic structures. Nafion was employed as the conducting matrix to help TiCNPs better attached onto the surface of the electrode and slow down the crystal rate of PtNFs during electrodeposition, which resulted in flower structure and more active surface of PtNFs. Taking advantage of synergistic effects of TiCNPs and Nafion as well as the catalytic amplifying effect of PtNFs, the excellent anodic signal responses for the voltammetric stripping determination of Fe(II) were obtained. The linear range of Fe(II) on this dual-nanomaterial based electrode was from 1 nmol L À 1 to 6 μmol L À 1 with the lowest detectable concentration of 0.1 nmol L À 1 and a detection limit of 0.03 nmol L À 1 . Additionally, the effect of several experimental parameters, such as concentration and pH value of buffer solution, concentration of modifier and ligand, deposition potential and time of electrochemical determination, and scan rate were studied for analytical applications. The fabricated sensor had been successfully applied for the sensitive determination of trace Fe(II) in coastal waters.

In-situ fabrication of reduced graphene oxide/leucomethylene blue/platinum nanoparticles modified electrode for voltammetric determination of trace Fe(II) in seawater

“…To evaluate the practical application of the established electrode, the rGO/LMB/PtNPs/GCE was employed to detect Fe(II) in standard artificial and seawater samples. As listed in Table 2, the amounts of Fe (II) in three real seawater samples 1 was calculated to be 23.3 nM, and in seawater sample 2 and sample 3, the concentrations were calculated to be 20.6 nM and 51.1 nM, respectively, Because the concentration of Fe(II) in seawater was very low and the determination of Fe(II) needed special treatment, the results were agreed with those measure by a reference method based on catalytic cathodic stripping voltammetry (CSV) [24]. In addition, the recoveries in a standard addition method were in the range of 92~101% in the real and artificial seawater samples.…”

“…Disposable screen printed electrode modified with imine receptor having a wedge bridge for selective detection of Fe (II) in T aqueous medium was used by Sonia, with the LOD of 0.54 μM [23]. In our previous work, a dual nanomaterial-modified electrode for voltammetric stripping determination of trace Fe(II) in coastal waters with a LOD of 0.03 nM was reported [24], but the process of making electrodes was rather complicated. The electrochemical detection of Fe(II) is feasible, but how to lower the detection limit is still a popular topic.…”

Voltammetric methods for speciation analysis of trace metals in natural waters

“…Aldrich et al ( 2001) used 2,2 0 -bipyridyl (Bp) as a masking agent for the selective determination of Fe(III) [128]. Lin et al (2016) adopted threedimensional platinum nanoflowers/titanium carbide nanoparticles modified GCE with Bp as the complexing agent for selective determination of Fe(Ⅱ) in coastal waters [129]. A Fe 2+ selective sensor was also fabricated by modifying a carbon screen-printed electrode with polypyrrole and sodium dodecyl sulfate [130].…”

Stripping Voltammetric Determination of Lead in Coastal Waters With a Functional Micro-Needle Electrode

“…As an efficient electrochemical technique for the determination of heavy metals, anodic stripping voltammetry (ASV) has attracted much attention due to its advantages, such as high sensitivity, rapid response, and straightforward analytical processes (Aragay et al, 2011b;Wang et al, 2014;Lin et al, 2016). In the past decades, mercury electrode, such as hanging mercury electrode, dropping mercury electrode, and mercury film electrode has been commonly adopted for the ASV determination of heavy metals (Nedeltcheva et al, 2005;Annibaldi et al, 2015;Granado-Castro et al, 2018).…”