Nanomaterials for Cultural Heritage Conservation

Nanomaterials have emerged as transformative tools in the conservation and restoration of cultural heritage, offering enhanced penetration, compatibility and longevity compared with traditional treatments. Among the most widely studied are calcium hydroxide nanoparticles (nanolimes), silica and titanium dioxide nanostructures, metal oxide nanocomposites and hybrid systems incorporating polymers or bio-inspired molecules. These materials can consolidate friable substrates, impart hydrophobicity, protect against microbial growth and reduce environmental deterioration. The high surface-to-volume ratio of nanoparticles promotes chemical reactivity and adhesion, while functionalisation strategies enable tailored interactions with diverse substrates such as limestone, mortar, wall paintings and wooden artefacts. Global interest spans preventive conservation in humid environments, consolidation of porous stones subject to salt crystallisation, and protective coatings for outdoor monuments. Practical applications have demonstrated improved mechanical strength, controlled pore structure modification and self-cleaning or antimicrobial properties, underscoring the potential of nanotechnology to extend the lifespan of invaluable works of art and architecture.

Research from Nature Portfolio

Researchers have shown that combining synthesised calcium carbonate polymorphs with nanolime suspensions can overcome limitations in consolidating highly porous limestone. Advanced imaging techniques revealed that the dual particle system fills pore networks more effectively than nanolime alone, reducing micrometric porosity without altering nanoscale fractal surfaces. The synergistic binding of CaCO₃ and Ca(OH)₂ particles strengthens the pore-matrix microstructure, with particle size and shape governing penetration depth and consolidation efficiency. This work highlights the benefit of integrating complementary nanomaterials to enhance stone decay mitigation.

Nanomaterials for Cultural Heritage Conservation publication trend

The graph below shows the total number of articles in nanomaterials for cultural heritage conservation across all publications each year (not limited to Nature Index journals).

Technical terms

Nanolime: Alcoholic or aqueous dispersion of calcium hydroxide nanoparticles used to consolidate calcareous substrates.

Polymorph: A solid material that can exist in more than one crystal structure, influencing its reactivity and mechanical behaviour.

Calcium silicate hydrate (CSH): A cementitious phase that forms from Ca(OH)₂ and silicate sources, enhancing bonding and strength in treated substrates.

Nanocomposite: A hybrid material combining nanoparticles with polymers or other matrices to achieve tailored mechanical and functional properties.

Porosity: The fraction of void space within a material, critical to fluid transport, consolidation penetration and durability of heritage substrates.

References

1. New nanomaterials for applications in conservation and restoration of stony materials: A review. Materiales de Construcción (2017).
2. Synthetic calcium carbonate improves the effectiveness of treatments with nanolime to contrast decay in highly porous limestone. Scientific Reports (2019).
3. Silica‐Functionalized Nanolimes for the Conservation of Stone Heritage. Small (2023).
4. New Perspectives for the Consolidation of Mural Paintings in Hypogea with an Innovative Aqueous Nanolime Dispersion, Characterized by Compatible, Sustainable, and Eco-Friendly Features. Nanomaterials (2023).
5. Effectiveness of Nanolime as a Stone Consolidant: A 4-Year Study of Six Common UK Limestones. Materials (2019).