Artigo de peri??dico
Titania-silica composite with photocatalytic properties and its application on Brazilian granite and sandstone
Registro en:
1558-3058
5
17
10.1080/15583058.2021.1969483
0000-0001-7384-304X
43.8
97.33
Autor
GROSSI, DANIELLE
LAZAR, DOLORES R.R.
DEL LAMA, ELIANE A.
USSUI, VALTER
Resumen
The aim of the study described in this article was to evaluate a product containing titania (titanium dioxide, TiO2) applied on stones ??? particularly two types used at Brazilian stone-built heritage sites ??? that have been exposed to weathering and anthropogenic activities. This product was prepared by producing a suspension of TiO2 at two concentrations (1% and 4% w/v) with tetraethyl orthosilicate (TEOS) in the presence of n-octylamine as surfactant. The characteristics of the TiO2 were then observed by scanning electron microscopy (SEM), Brunauer-Emmett-Teller (BET) surface-area measurements, particle-size distribution analysis (CILAS) and X-ray diffraction. After applying the TiO2-TEOS composite, the stones were examined for contact angle, spectrophotometry, sorptivity, thermal shock resistance, and UV-radiation resistance. The product proved ineffective on Itarar?? sandstone, mainly due to its mineralogical components, as the product does not adhere to quartz. When applied on Itaquera granite, the 1% TiO2 (w/v) concentration proved to be an appropriate treatment, as it demonstrated better thermal shock resistance, photocatalytic activity, porosity maintenance, and global colour when compared to the 4% concentration. Coordena????o de Aperfei??oamento de Pessoal de N??vel Superior (CAPES) CAPES: 88882.315495/201901