Topic
Plattnerite
About: Plattnerite is a research topic. Over the lifetime, 20 publications have been published within this topic receiving 588 citations.
Papers
TL;DR: The Raman spectra of plattnerite, lead(IV) oxide, PbO2 and of the lead pigments red lead, lead monoxide, lead white, and of their laser-induced degradation products were recorded using a range of different excitation lines, spectrometer systems and experimental conditions.
Abstract: The Raman spectra of plattnerite [lead(IV) oxide,
PbO2] and of the lead pigments red lead
(Pb3O4), lead monoxide [PbO, litharge (tetragonal)
and massicot (orthorhombic)], lead white [basic lead carbonate,
2PbCO3·Pb(OH)2] and of their laser-induced
degradation products were recorded using a range of different excitation
lines, spectrometer systems and experimental conditions. The degradation of
PbO2 is more extensive along the pathway PbO2
→
Pb3O4
→ PbO (litharge) → PbO (massicot) the
shorter the wavelength of the excitation line and the higher its power. The
Raman spectrum of PbO2, which is black and of the rutile
structure, is particularly difficult to obtain but three bands, at 653, 515
and 424 cm−1, were identified as arising from the
b2g, a1g and eg modes respectively, by
analogy with the corresponding modes of isostructural SnO2 (776,
634 and 475 cm−1). A further oxide was identified,
PbO1.55, the Raman spectrum of which does not correspond to that
of any of the laser-induced degradation products of PbO2 at any
of the wavelengths used. The Raman results are critical to the future use
of Raman microscopy for the identification of lead pigments on
artworks.
267 citations
TL;DR: X-ray powder diffraction tomography, a powerful analytical method that allows visualization of the internal distribution of different crystalline compounds in complex samples, was used to investigate a microscopic paint sample from a Van Gogh painting and a very rare lead mineral, plumbonacrite, was revealed to be present.
Abstract: Red lead, a semiconductor pigment used by artists since antiquity, is known to undergo several discoloration phenomena. These transformations are either described as darkening of the pigment caused by the formation of either plattnerite (b-PbO2) or galena (PbS) or as whitening by which red lead is converted into anglesite (PbSO4) or (hydro)cer- ussite (2 PbCO3·Pb(OH)2; PbCO3). X-ray powder diffraction tomography, a powerful analytical method that allows visual- ization of the internal distribution of different crystalline compounds in complex samples, was used to investigate a microscopic paint sample from a Van Gogh painting. A very rare lead mineral, plumbonacrite (3 PbCO3· Pb(OH)2·PbO), was revealed to be present. This is the first reported occurrence of this compound in a painting dating from before the mid 20th century. It constitutes the missing link between on the one hand the photoinduced reduction of red lead and on the other hand (hydro)cerussite, and thus sheds new light on the whitening of red lead.
75 citations
TL;DR: In this article, the results were used to interpret colour changes observed in 11th-century frescoes from the church of Saint George in Kostoľany pod Tribecom, the oldest preserved wall paintings in Slovakia.
73 citations
TL;DR: A conceptual model of lead(IV) oxide formation pathways was proposed based on the experimental results and it was proposed that intermediate solids formed that affected the identity of the PbO(2) produced.
Abstract: Lead(IV) oxide (PbO(2)) is a corrosion product that can develop on lead pipes used for drinking water supply, and its stability can control lead concentrations in tap water. A set of batch experiments were performed to determine the extent of PbO(2) formation as a function of time, pH, the presence of dissolved inorganic carbon (DIC), and free chlorine concentration. Experiments were conducted with four lead(II) compounds that are precursors of PbO(2) formation: dissolved lead(II) chloride, massicot (β-PbO), cerussite (PbCO(3)), and hydrocerussite (Pb(3)(OH)(2)(CO(3))(2)). While PbO(2) formed in the presence and absence of DIC, the presence of DIC accelerated PbO(2) formation and affected the identity of the PbO(2) (scrutinyite vs plattnerite) product. For some conditions, intermediate solids formed that affected the identity of the PbO(2) produced. When no intermediate solids formed, hydrocerussite led to the formation of pure scrutinyite, and lead(II) chloride and massicot led to mixtures of scrutinyite and plattnerite. Based on the experimental results, a conceptual model of lead(IV) oxide formation pathways was proposed.
63 citations
TL;DR: The objectives of this study were to quantify plattnerite dissolution rates in the presence of chlorine disinfectants, gain insights into dissolution mechanisms, and measure plattNERite's equilibrium solubility in the absence of free chlorine.
Abstract: Plattnerite (β-PbO2) is a corrosion product that develops on lead pipes that have been in contact with free chlorine present as a residual disinfectant. The reductive dissolution of PbO2 can cause elevated lead concentrations in tap water when the residual disinfectant is switched from free chlorine to monochloramine. The objectives of this study were to quantify plattnerite dissolution rates in the presence of chlorine disinfectants, gain insights into dissolution mechanisms, and measure plattnerite’s equilibrium solubility in the presence of free chlorine. The effects of free chlorine and monochloramine on the dissolution rates of plattnerite were quantified in completely mixed continuous-flow reactors at relevant pH and dissolved inorganic carbon conditions. Plattnerite dissolution rates decreased in the following order: no disinfectant > monochloramine > chlorine, which was consistent with the trend in the redox potential. Compared with experiments without disinfectant, monochloramine inhibited plattn...
55 citations
Related Topics (5)
Performance Metrics
| Year | Papers |
|---|---|
| 2021 | 1 |
| 2020 | 2 |
| 2015 | 2 |
| 2014 | 1 |
| 2013 | 1 |
| 2012 | 1 |