Electrodeposition of Lead at Boron‐Doped Diamond Film Electrodes: Effect of Temperature

Abstract

The electrodeposition of lead on boron-doped diamond has been studied with a view to identifying the fundamental parameters controlling the sensitivity and lower detection limit in anodic stripping voltammetry. Chronoamperometric transients are used to explore the deposition, indicating a progressive growth mechanism confirmed by ex situ AFM images. Linear sweep ASV experiments show a threshold concentration of ca 10 À6 M below which no lead is detected; this is attributed to the need for nucleation of the solid phase on the electrode. Experiments with variable temperature show that this threshold can be usefully lowered at elevated temperatures.

Interaction between co-deposited metals during stripping voltammetry at boron-doped diamond electrodes

“…The data in Figs. 1 and 2, confirm previous studies, 10,14,16 which show that diamond performs well in this application for the analysis of solutions containing a single reducible metal ion. The rapid growth of an adherent deposit in electrical communication with the underlying electrode, occurs during the preconcentration stage, resulting in a well-defined and therefore easily quantifiable stripping peak as the electrode is scanned to positive potentials, which shows a linear dependence on ion concentration in solution.…”

“…2, associated with the formation of Pb nuclei on the diamond surface. In this case, particularly at higher Pb loadings, a significant amount of the deposited Pb is extremely difficult to remove electrochemically from the electrode surface 14,16 resulting in a prominent tail of the main stripping peak.…”

“…[2][3][4][5][6][7][8][9][10][11] Indeed, diamond electrodes seem to possess many of the electrochemical attributes of their mercury counterparts and are therefore being investigated as non-toxic materials for use in ASV. [10][11][12][13][14][15][16][17][18] For practical applications of ASV, it is frequently the case that several different metals are deposited at the electrode during the preconcentration stage. This is generally not problematic for Hg electrodes, where the deposit forms an amalgam within the volume of the Hg present.…”

A versatile and robust electrochemical flow cell with a boron-doped diamond electrode for simultaneous determination of Zn2+and Pb2+ions in water samples

“…2 In this context, electroactive cations, such as Cd 2+ , Pb 2+ , Cu 2+ , Zn 2+ , Ag + , Pd 2+ , and Hg 2+ , have been determined by employing BDD in various samples, resulting in detection limits as low as mg L À1 or ng L À1 , using differential pulse anodic stripping voltammetry (DPASV) or square-wave anodic stripping voltammetry (SWASV). 2,[12][13][14][15][16][17] A very interesting application of BDD electrodes using these techniques involves the possibility of simultaneous determination. 2,14 However, in batch analysis, the sampling frequency is not favorable, due to the preconcentration steps, which make its use difficult in routine analysis or for a larger number of samples.…”

Direct Identification and Analysis of Heavy Metals in Solution (Hg, Cu, Pb, Zn, Ni) by Use of in Situ Electrochemical X-ray Fluorescence

“…26 Prior to use, BDD electrodes were acid-cleaned by boiling in concentrated H 2 SO 4 (98%), supersaturated with KNO 3 in order to remove any nondiamond-carbon (NDC) from the laser micromachining process. 27 BDD 1 mm diameter glass-sealed macroelectrodes were prepared as described previously. 26,28 In Situ Electrochemical X-ray Fluorescence Apparatus and Operation.…”