International Journal of Architectural Heritage ( IF 2.4 ) Pub Date : 2021-09-13 , DOI: 10.1080/15583058.2021.1969483 Danielle Grossi 1 , Dolores Ribeiro Ricci Lazar 2 , Eliane Aparecida Del Lama 1 , Valter Ussui 2
ABSTRACT
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 Itararé 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.
中文翻译:
具有光催化性能的二氧化钛-二氧化硅复合材料及其在巴西花岗岩和砂岩上的应用
摘要
这篇文章中描述的研究的目的是评估一种包含二氧化钛(二氧化钛,TiO 2)的产品,该产品应用于已经暴露于风化和人为活动的石头——特别是巴西石头建造的遗产地使用的两种类型。该产品是通过在正辛胺作为表面活性剂存在的情况下,用原硅酸四乙酯 (TEOS) 制备两种浓度(1% 和 4% w/v)的TiO 2悬浮液来制备的。然后通过扫描电子显微镜 (SEM)、Brunauer-Emmett-Teller (BET) 表面积测量、粒度分布分析 (CILAS) 和 X 射线衍射观察 TiO 2 的特性。应用 TiO 2后-TEOS 复合材料,检查了宝石的接触角、分光光度法、吸附率、抗热震性和抗紫外线辐射性。该产品被证明对 Itararé 砂岩无效,主要是由于其矿物成分,因为该产品不粘附在石英上。当应用于 Itaquera 花岗岩时,1% TiO 2 (w/v) 浓度被证明是一种合适的处理方法,因为与 4% 浓度相比,它表现出更好的抗热震性、光催化活性、孔隙率保持和整体颜色。