Preserving cultural heritage stone: Innovative consolidant, superhydrophobic, self-cleaning, and biocidal products

Abstract

Most products commonly employed in the restoration and conservation of cultural heritage stone have not been specifically developed to preserve such elements. In addition, they are plagued by limited performance and structural drawbacks such as low adhesion, poor penetration, and cracking. Another disadvantage is the requirement for most products to be dissolved in volatile organic compounds (VOCs), which produce environmental and human health risks in their use. An innovative sol–gel route for preserving cultural heritage stonework has been developed and is discussed herein. Specifically, a surfactant-assisted sol–gel synthesis produces, in situ on the stonework, crack-free nanomaterials to be used as long-term consolidants. Additionally, hydrophobic, water-repellent, self-cleaning, and biocidal properties can be incorporated into the product by innovative chemical modifications of the proposed synthesis route.