The photo-reactivity of artistic pigments: from the preservation of historical paintings to new opportunities as singlet oxygen generators

Singlet oxygen (SO) is one of the reactive oxygen species known for being a strong oxidant. There are materials, called SO generators, that produce SO under light exposure and in presence of oxygen. SO generators can be found even among the pigments used in historical paintings.

SO has a huge impact in the preservation of these historical paintings since it reacts with the binding media and other artistic pigments causing degradation processes that compromises their integrity.The main goal of the PHOTOELECTROART project is to understand I) the photo-reactivity of artistic pigments that generate SO, II) the impact of the environment and microenvironment in the amount of SO emitted by these substances and III) how this can be applied to improve the preservation of historical paintings containing SO generator pigments.

To achieve this, PHOTOELECTROART will exploit a highly interdisciplinary methodological process based on photo-electrochemistry and infrared spectroscopy, including IR nanospectroscopy.Results will have a major impact in the understanding of the role of the SO emitted by the pigments in the alterations of the historical paintings where these are found, providing a detailed knowledge of the degradation reactions throughout the painting’s history and helping to find suitable mitigation actions to preserve the cultural heritage.

Additionally, the results will provide new information on the conditions that boost the generation of SO from those pigments: this new knowledge will contribute to the development of innovative applications in fields where a high production of SO is needed, such as treatment of wastewaters and medical therapies.