Electrodes, bismuth modified

Macia MD, Herrero E, Fehu JM, Aldaz A. 1999. Fomtic acid self-poisoning on bismuth-modified Pt(755) and Pt(775) electrodes. Electrochem Commun 1 87-89. 

Smith PE, Ben-Dor KF, Abruna HD. 2000. Poison formation upon the dissociative adsorption of formic acid on bismuth-modified stepped platinum electrodes. Langmuir 16 787-794. 

Herteto E, Rodes A, Perez JM, Feliu JM, Aldaz A. 1995d. CO adsorption and oxidation on Pt(lll) electrodes modified by irreversibly adsorbed arsenic in sulfimc-acid medium— Comparison with bismuth-modified electrodes. J Electroanal Chem 393 87-96. 

Smith SPE, Ahruna HD. 1999a. Structural effects on the oxidation of HCOOH by bismuth modified Pt(lll) electrodes with (110) monatomic steps. J Electroanal Chem 467 43-49. 

Svancara, I., Baldrianova, L., Tesarova, E., Hocevar, S. B., Elsuccary, S. A. A., Economou, A., Sotiropoulos, S., Ogorevc, B. and Vytras, K. (2006), Recent advances in anodic stripping voltammetry with bismuth-modified carbon paste electrodes. Electroanalysis, 18(2) 177-185. 

What, if any, relevance do such results have when predicting the influence of adsorbed bismuth on the CO of supported platinum nanoparticle catalysts In order to test the transferrability of results obtained on single crystals to practical fuel-cell anode catalysts, a series of experiments was performed [77] on a gas diffusion electrode of carbon-supported platinum (0.22 mg cm ) catalyst (Johnson Matthey). Figure 10 shows the results of polarization measurements for hydrogen oxidation at clean and bismuth-modified (0.65-ML) catalysts. In order to establish the CO tolerance of the electrodes, in addition to experiments involving pure H2,... 

Bismuth has attracted significant interest as a Pt/C modifier for formic acid electrooxidation [21, 24, 26, 27]. A wide range of stable and well-characterized electrode surfaces modified by irreversible Bi adatom adsorption on Pt have been reported in the literature for a range of Bi coverages 6). Chen et al. have explored Bi adatom decoration on 81 nm tetrahexahedral Pt nanoparticles that while composed of (100) and (110) facets that are the least active for formic acid electrooxidation, they are boimd by 730 and vicinal high-index facets that are extremely active [18]. They have measured current densities of 10 mA cm for Bi coverages up to 0.9 at 0.4 V in 0.25 M formic acid and 0.5 M H2SO4 solution see Fig. 4.4. They also showed steady-state activity at 0.3 V of 2.8 mA cm after 1 min vs. 0.0003 mA cm for the non-modified Pt baseline. 

The use of bismuth modified electrodes (through ex-situ and in-situ) modification has become a backbone of the electroanalytical community for a variety of target analytes [23]. 

Arduini F, Quintana Calvo J, Amine A, Palleschi G, Moscone D (2010) Bismuth-modified electrodes for lead detection (a review). Trends Anal Chem 29(2010) 1295-1304... 

Svancara I, Prior C, Hocevar SB, Wang J (2010) A decade of bismuth-modified electrodes in electroanalysis. Electroanalysis 22 1405-1420... 

Kirgbz UA, Marin S, Pumera M, Merkofi A, Alegret S (2005) Stripping voltammetry with bismuth modified graphite-epoxy composite electrodes. Electroanalysis 17 881-886... 

Calvo Quintana J, Arduini F, Amine A, van Velzai K, Palleschi G, Moscone D (2012) Part two analytical optimisation of a procedure for lead detectiscreen-printed electrodes. Anal Chim Acta 736 92-99... 

Wang N, Dong X (2008) Stripping voltammetric determination of Pb(II) and Cd(II) based on the multiwalled carbon nanotubes-nafion-bismuth modified glassy carbon electrodes. Anal Lett 41 1267-1278... 

Svancara I, Baldrianova L, Tesarova E, Mikysek T, Vytfas K (2007) Anodic stripping voltammetry at bismuth-modified electrodes in ammonia-buffered media. Sci Pap Univ Pardubice A 12 5-19... 

Svancara I, Baldrianova L, TesMova E, Mikysek T, Vytras K (2005) Determination of tin (II) at bismuth-modified carbon paste electrodes. Initial study (in Czech). In Vytras K, Kellner J, Fischer J (eds) Monitoring of environmental pollutants, vol VII. Univ. Pardubice Press Centre, Pardubice, Czech Rep, pp 139-148... 

Another possibility is to use bismuth-film-modified electrodes which were used, e.g., for detection of picric acid. Different types of bismuth-based electrodes (bismuth-film electrodes, bismuth bulk electrodes, bismuth-nanoparticle-modified electrodes) and their applications for determination of (among others) various nitrocompounds were reviewed. 

Henero E, Femandez-Vega A, Feliu JM, Aldaz A. 1993. Poison formation reaction from formic acid and methanol on platinum (111) electrodes modified by irreversibly adsorbed bismuth and arsenic. J Electroanal Chem 350 73-88. 

In this paper we report the application of bimetallic catalysts which were prepared by consecutive reduction of a submonolayer of bismuth promoter onto the surface of platinum. The technique of modifying metal surfaces at controlled electrode potential with a monolayer or sub-monolayer of foreign metal ("underpotential" deposition) is widely used in electrocatalysis (77,72). Here we apply the theory of underpotential metal deposition without the use of a potentiostat. The catalyst potential during promotion was controlled by proper selection of the reducing agent (hydrogen), pH and metal ion concentration. 

STRIPPING ANALYSIS WITH GRAPHITE-EPOXY ELECTRODES MODIFIED WITH BISMUTH NITRATE... 

This potential, adjusted as a function of the pH of the solution and of the hydrogen pressure, is easily fixed between +0 1 V and — 0.9V/NHE (Normal Hydrogen Electrode). The H2/H+ couple was used to prepare supported catalysts with platinum, palladium, ruthenium, and rhodium modified with deposits of tin, lead, iron, germanium, and bismuth [50-54]. These catalysts were proposed for their good selectivities for different reactions in specialize organic chemistry. 

Lead perchlorate and bismuth nitrate were added to the electrolytic solution at 5 x 10-5 and 10 5 M, respectively, to modify a platinum electrode, which has a real surface area of 40 cm2. The electrolysis cell has two identical compartments separated by an ion-exchange membrane (Nation 423). A Ptgolrio sheet and the Hg/Hg2S04, SOf s i, electrode served as counter and reference electrodes, respectively. 

We have developed nanoparticle label-based electrochemical immunoassay of OP exposure biomarkers, OP-ChE (44). The principle and procedure of this method is shown in Figure 5. Here, zircomia (Zr02) NPs, electrochemically deposited on the electrode surface, which functioned as the capture antibodies in the sandwich immunoassay. The zirconia- NP- modified electrode is then exposed to the sample solution and the ChE-OP in the sample is captured by the Zr02 nanoparticles. The QD-tagged, anti-AChE conjugate is introduced to form the sandwich-like complex on the sensor surface. The captured QDs are then dissolved by a drop of acid to release cadmium ions. This is followed by square wave voltammetric (SWV) [abbreviation already introduced but unexplained] detection of the released cadmium ions at an in situ plated mercury/bismuth film electrode. 

Stoces, M. and Svancara, I. (2013) Bismuth-trifluoride modified carbon paste electrode for electrochemical stripping analysis of heavy metals. Int. 

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