Photocatalytic Nanocomposites for the Protection of European Architectural Heritage
Abstract
:1. Introduction
2. Materials and Methods
2.1. Set-Up of Nanomaterials
- -
- the first nanocomposite, labeled WNC, is a formulation based on alkyl alkoxy silane oligomers (15% w/w) with TiO2 NPs (0.96% w/w) in water; and,
- -
- the second nanocomposite, labeled ANC, is based on alkyl alkoxy silane monomers (40% w/w) with TiO2 NPs (0.12% w/w) in 2-propanol.
2.2. Set-Up of Treated Specimens for Testing
2.3. Characterization of the Nanocomposites
2.4. Evaluation of the Performances of Nanocomposites
3. Results and Discussion
3.1. Characterization of the Nanocomposites
3.2. Evaluation of the Surface Morphology of the Treated Specimens
3.3. Evaluation of the Surface Colour Compatibility
3.4. Evaluation of the Surface Wettability, Water Absorption and Water Vapour Permeability
3.5. Evaluation of the Photocatalytic Activity of the Nanocomposites
4. Conclusions
Supplementary Materials
Acknowledgments
Author Contributions
Conflicts of Interest
References
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Treatment | Apuan Marble | Ajarte |
---|---|---|
WNC | 0.3 ± 0.2 | 37 ± 5 |
ANC | 1.3 ± 0.1 | 50 ± 6 |
Lithotype | Total Open Porosity | Average Pore Diameter |
---|---|---|
Apuan marble | 0.7 | 0.08 |
Ajarte | 23.5 | 0.17 |
Lithotype | Treatment | ΔL* | Δa* | Δb* | ΔE* |
---|---|---|---|---|---|
Apuan marble | SILRES BS 290 | −1.69 ± 0.91 | 0.01 ± 0.01 | 0.50 ± 0.24 | 1.77 ± 0.92 |
WNC | −1.23 ± 0.45 | −0.14 ± 0.17 | 0.73 ± 0.60 | 1.52 ± 0.54 | |
ANC | −2.69 ± 0.76 | −0.05 ± 0.02 | 0.56 ± 0.11 | 2.75 ± 0.76 | |
Ajarte | SILRES BS 290 | −5.40 ± 0.85 | 0.52 ± 0.08 | 2.06 ± 0.34 | 5.80 ± 0.91 |
WNC | −0.94 ± 0.29 | −0.36 ± 0.06 | 1.08 ± 0.25 | 1.50 ± 0.28 | |
ANC | −1.97 ± 0.77 | 0.21 ± 0.09 | −0.28 ± 0.87 | 2.19 ± 0.64 |
Treatment | θ° nt | θ° t | CIrel | Qi nt | Qi t | CI nt | CI t | AC nt | AC t | δ t /δ nt |
---|---|---|---|---|---|---|---|---|---|---|
SILRES BS 290 | 58 ± 11 | 101 ± 5 | 0.17 ± 0.03 | 4.02 ± 1.24 | 0.80 ± 1.11 | 0.88 ± 0.11 | 0.75 ± 0.55 | 0.05 ± 0.04 | 0.003 ± 0.003 | 0.29 ± 0.22 |
WNC | 66 ± 10 | 114 ± 1 | 0.75 ± 0.05 | 4.56 ± 2.64 | 3.61 ± 2.34 | 0.83 ± 0.08 | 0.81 ± 0.07 | 0.07 ± 0.07 | 0.026 ± 0.011 | 1.17 ± 0.38 |
ANC | 72 ± 18 | 130 ± 10 | 0.13 ± 0.02 | 3.50 ± 0.17 | 0.57 ± 0.10 | 0.86 ± 0.04 | 0.70 ± 0.10 | 0.03 ± 0.01 | 0.006 ± 0.0004 | 0.91 ± 0.21 |
Treatment | θ° nt | θ° t | CIrel | Qi nt | Qi t | CI nt | CI t | AC nt | AC t | δ t /δ nt |
---|---|---|---|---|---|---|---|---|---|---|
SILRES BS 290 | - | 138 ± 7 | 0.07 ± 0.01 | 420.70 ± 11.94 | 48.18 ± 13.42 | 0.86 ± 0.01 | 0.51 ± 0.03 | 4.80 ± 0.98 | 0.06 ± 0.01 | 0.31 ± 0.03 |
WNC | - | 122 ± 7 | 0.16 ± 0.01 | 441.87 ± 22.94 | 105.56 ± 7.43 | 0.86 ± 0.01 | 0.56 ± 0.02 | 4.60 ± 1.33 | 0.21 ± 0.07 | 0.64 ± 0.09 |
ANC | - | 141 ± 2 | 0.04 ± 0.01 | 415.71 ± 20.26 | 24.41 ± 3.56 | 0.85 ± 0.01 | 0.59 ± 0.02 | 4.48 ± 0.87 | 0.04 ± 0.01 | 0.44 ± 0.03 |
Apuan Marble | Ajarte | |||
---|---|---|---|---|
Time (min.) | D*WNC/D*Silres | D*ANC/D*Silres | D*WNC/D*Silres | D*ANC/D*Silres |
30 | 2.16 | 0.71 | 5.64 | 0.15 |
40 | 1.86 | 0.75 | 6.40 | 1.14 |
90 | 1.58 | 0.76 | 3.90 | 1.95 |
150 | 1.34 | 1.30 | 3.31 | 2.00 |
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Gherardi, F.; Roveri, M.; Goidanich, S.; Toniolo, L. Photocatalytic Nanocomposites for the Protection of European Architectural Heritage. Materials 2018, 11, 65. https://doi.org/10.3390/ma11010065
Gherardi F, Roveri M, Goidanich S, Toniolo L. Photocatalytic Nanocomposites for the Protection of European Architectural Heritage. Materials. 2018; 11(1):65. https://doi.org/10.3390/ma11010065
Chicago/Turabian StyleGherardi, Francesca, Marco Roveri, Sara Goidanich, and Lucia Toniolo. 2018. "Photocatalytic Nanocomposites for the Protection of European Architectural Heritage" Materials 11, no. 1: 65. https://doi.org/10.3390/ma11010065
APA StyleGherardi, F., Roveri, M., Goidanich, S., & Toniolo, L. (2018). Photocatalytic Nanocomposites for the Protection of European Architectural Heritage. Materials, 11(1), 65. https://doi.org/10.3390/ma11010065