On the photoluminescence changes induced by ageing processes on zinc white paints

Artesani, Alessia and Gherardi, Francesca and Mosca, Sara and Alberti, Roberto and Nevin, Austin and Toniolo, Lucia and Valentini, Gianluca and Comelli, Daniela (2018) On the photoluminescence changes induced by ageing processes on zinc white paints. Microchemical Journal, 139 . pp. 467-474. ISSN 0026-265X

Documents
AS6098408628756491522408800440_content_1.pdf

Request a copy
31532 Accepted manuscript.pdf
[img]
[Download]
[img] PDF
AS6098408628756491522408800440_content_1.pdf - Whole Document
Restricted to Repository staff only

1MB
[img]
Preview
PDF
31532 Accepted manuscript.pdf - Whole Document

4MB
Item Type:Article
Item Status:Live Archive

Abstract

Recent research is focusing on the study of interaction mechanisms between pigments and binders, as they are crucial for understanding paint ageing and conservation issues. In this work, we investigate these mechanisms and follow the changes induced by ageing on zinc white paint by employing Fourier Transform Infrared (FTIR) and Time-Resolved Photoluminescence (TRPL) spectroscopies. The two techniques, applied on thermally aged mock-up samples and on a 19th oil painting, provide complementary information on the effect of the binder on the ZnO pigment particles. The characterization of the infrared absorption spectra confirms the well-known tendency of amorphous metal carboxylate formation in zinc white paint following ageing. At the same time, the ageing of paint film produces significant changes in the photoluminescence emission from defect centres of ZnO. The emission that is mostly affected by the changes of the micro-environment is the blue band (430 nm) – associated with surface defects – whereas the green emission (530 nm) is stable. The results demonstrate that the evolution of the pigment-binder system has detectable consequences on the crystalline structure of the pigment particles and we speculate that the main cause of these modifications is the functionalization of the pigment particle surfaces. The possibility to follow crystal structure changes with time-resolved photoluminescence can thus support chemical studies on metal carboxylate formation and paint deterioration by providing information about pigment-binder interactions.

Keywords:zinc white, metal soap, thermal ageing, Painting, Time resolved photoluminescence, FTIR
Subjects:F Physical Sciences > F200 Materials Science
Divisions:College of Science > School of Chemistry
Related URLs:
ID Code:31532
Deposited On:10 Apr 2018 10:10

Repository Staff Only: item control page