Exploiting Chemistry to Improve Performance of Screen-Printed, Bismuth Film Electrodes (SP-BiFE)

Abstract

Mercury substitution is a big issue in electroanalysis, and the search for a suitable, and less toxic, replacement is still under development. Of all the proposed alternatives, bismuth films appear to be the most viable solution, although they are still suffering some drawbacks, particularly the influence of deposition conditions and linearity at low concentrations. In this paper, the most promising strategies for bismuth film deposition on screen-printed electrodes (surface modifications, polymeric film deposition, insoluble salt precursors) will be evaluated for trace metal analysis. Particular attention will be devoted to bismuth chemistry, aiming to rationalize their electroanalytic performance.

Determination of Zinc, Cadmium, Lead, Copper and Silver Using a Carbon Paste Electrode and a Screen Printed Electrode Modified with Chromium(III) Oxide

“…They also show good reproducibility of measurements, and the foil SPE is portable, has a high sensitivity and is relatively easy to dispose of. In combination with a portable potentiostat, it allows for easy in situ measurements [ 2 , 16 , 17 , 18 ]. This shows that SPEs provide very good alternatives to other types of working electrodes including mercury ones.…”

Exploiting Laser-Ablation ICP-MS for the Characterization of Salt-Derived Bismuth Films on Screen-Printed Electrodes: A Preliminary Investigation

“…The concentration of bismuth in the pre-deposited BiPO 4 phase as a precursor of the active Bi 0 metal phase in screen-printed electrodes is known to have a profound effect on analytical performances. In both References [13,17], the best performances are shown by the lowest Bi concentration, with an ideal value around 1 mM in terms of peak shape and increased linearity at low analyte concentrations. For laser ablation studies, instead, the need to increase bismuth loadings was immediately evident, with respect to the best working low-loading electrode, in order to increase signal-to-noise ratios.…”

“…Pristine screen-printed electrodes have been used as received after cleaning in HCl solution. Polystyrene sulfonate (PSS)-modified Bi/PO 4 electrodes were prepared via deposition of the polymer layer and of the insoluble bismuth phosphate, following the 2-step recipe in Reference [13]:…”

“…This process is not a facile one, since it is reported to be sensitive to the nature of the bismuth precursor, the possible occurrence of kinetics limitations, and the sensitivity to the cleanliness of the carbon surface of the working electrode [11,12]. This wide range of experimental conditions leading to the optimal and active bismuth film may be rationalized on the basis of the rich chemistry of bismuth in aqueous solutions [13]. In this context, a decisive advantage was gained applying surface modification with polymers: this treatment permits to mitigate interferences and to improve the mechanical stability of the bismuth film [14,15].…”

Screen-Printed Electrodes Modified with “Green” Metals for Electrochemical Stripping Analysis of Toxic Elements

“…A similar approach was proposed for the surface modification of an SPE with insoluble Bi salts (BiPO 4 and BiVO 4 ) using either Nafion or PSS membranes [ 109 ]; these sensors offered higher sensitivity for Pb and Cd detection by ASV compared with SPEs similarly modified with a soluble Bi salt (Bi(NO 3 ) 3 ).…”