Present and Future Perspectives for Biocides and Antifouling Products for Stone-Built Cultural Heritage: Ionic Liquids as a Challenging Alternative

This review offers an overview of the most recent research activities on counteracting the biodeterioration process of stone monuments, underlining all those aspects regarding eventual procedural drawbacks and compliance with sustainable criteria. For this purpose, the definition of “green conservation of cultural heritage” has been proposed. Its basics have been utilized in the text to highlight the issues arising from the most common conservative procedures as well as guidelines for the development of innovative technologies. The review then deals with the most innovative antimicrobial approaches, among which nano- and bio-technologies play a main role. Ionic liquids are a special class of salts, which can be prepared by applying Safe by Design concepts, to meet the Green Conservation criteria.