Identification of lead pigments in nanosamples from ancient paintings and polychromed sculptures using voltammetry of nanoparticles/atomic force microscopy

Electroanalytical chemistry for the analysis of solids: Characterization and classification (IUPAC Technical Report)

“…Peak potentials and peak currents from cyclic, differential pulse, and square-wave voltammetries are typically used for the purpose of identification, but other parameters characterizing the shape of the voltammetric curves (peak width, peak to half peak separation, onset potentials), including Tafel slopes and ordinates at the origin can be used [206,207], and peak current and/or peak area ratios [149,208]. Principal component [209] and cluster analysis [149,195] multivariate chemometric methods have been applied to SSEAC.…”

Development of analytical methods for the characterization of tempera paintings at micro- and nano-scale and their deterioration and biodeterioration processes.

“…However, most research published on the use of electrochemical techniques to the analysis of artworks is based on the application of these techniques for the identification and characterization of binding media and dyes due to the development of new methodologies as VMP (Scholz and Meyer, 1994). This technique has been widely applied by to the field of organic compounds present in cultural goods VMP has been applied by these authors for the simultaneous determination of lead pigments and binding media in paint samples in the range of μg-pg (Doménech-Carbó et al, 2007b). A few nanograms of sample are mechanically attached to a paraffin-impregnated graphite electrode producing well defined square wave voltammetric responses for reconstructed model paint specimens.…”

“…The formation of different copper deposits results from the superposition of different reductive process and can proceed via topotactic conversion of copper acetate into Cu, as described for several lead compounds ) but can also involve intermediate species solution (Doménech-Carbó et al, 2007b).…”

“…In the subsequent anodic scan, a predominant oxidation peak at -0.50 V (A 1 ) was recorded. The reduction of lead white can be described in terms of the conversion of lead basic carbonate into metallic lead, as described for several lead compounds but also involving intermediate species in solution (Doménech-Carbó et al, 2000, 2007b, the reduction process C 1 plus C 2 can be described as: The peak A 1 corresponds to the well-known oxidative dissolution of the deposit of lead metal electrochemically generated in the cathodic process C 1 (Pb solid Pb 2+ aq + 2e -). This signal often looks like several superimposed signals, a feature which can be attributed to the superposition of the oxidation processes of different deposits of metallic lead, as described for verdigris pigment (Doménech-Carbó et al, 2007b).…”

“…This voltammetry can be described as resulting from the superposition of different electrochemical process and assuming that the paint film specimen is constituted by a more or less homogeneous distribution of pigment particles partially embedded by a layer of binder and an ionomeric layer, as described for lead pictorial layers (Doménech-Carbó et al, 2007b). As can be seen in Figure 10.1.5.3.2, in the initial cathodic scan CVs, the peak C 1 became lowered relative to the signal C 2 which was preceded by an additional cathodic signal at ca.…”