Photocatalytic activity, water absorption capacity, and thermal stability of white cement-based mortars with polysiloxane silicone and different doses of titanium dioxide nanoparticles
Actividad fotocatalítica, absorción de agua y estabilidad térmica de morteros a base de cemento blanco con silicona de polisiloxano y diferentes dosis de nanopartículas de dióxido de titanio
Cienc. tecnol. salud; 9 (1), 2022
Publication year: 2022
White cement-based mortars in urban areas are usually discolored and altered their esthetic properties due to air pollutants. The addition of nanoparticles in these mortars can provide photocatalytic properties that can decompose pollution agents. Likewise, other hydrophobic agents have been individually studied to improve outdoor building constructions. Therefore, this study presented the photocatalytic and hydrophobic effect of adding nano-TiO2and silicone hydrophobic powder (DOWSILTM) in a white cement matrix. The nano-TiO2 were characterized by X-Ray Diffraction (XRD); afterwards, the mortar was mixed with additions of nano-TiO2 (0.0, 0.5, 1.0, 3.0%) and DOWSILTM (0.0, 0.5%). The mortar’s photocatalytic performance was evaluated using a modification of the standard Italian test Ente Nazionale Italiano di Unificazione 11259:2016 based on Rhodamine B (RhB) degradation on the sample exposed to UV irradiation. Therefore, mortar samples were subjected to UV irradiation to degrade the organic dye rhodamine B, monitoring their color variation using a C I E L* a* b* spectrophotometer. Moreover, the water permeability and the contact angle were evaluated. This research demonstrates that the white cement-based mortar samples added with nano-TiO2/DOWSILTM possess photocatalytic activity. The samples with the addition of 1.0%/0.5% and 3.0%/0.5% nano-TiO2/DOWSILTM showed a higher RhB degradation for R4 and R26. Therefore, these two materials can be employed in these proportions to improve the quality of the white cement-based mortars in urban constructions.
Los morteros a base de cemento blanco generalmente se decoloran y alteran sus propiedades estéticas debido a los contaminantes del aire en las áreas urbanas. Nanopartículas añadidas a estos morteros pueden proporcionar propiedades fotocatalíticas que descomponen estos contaminantes. Asimismo, otros agentes hidrofóbicos se han estu-diado individualmente para mejorar las construcciones a la intemperie. Por lo tanto, se presenta el efecto fotocatalítico e hidrofóbico al incorporar nano-TiO2 y silicona hidrofóbica de polisiloxano (DOWSILTM) en una matriz de cemento blanco. El nano-TiO2 se caracterizó por medio de Difracción de Rayos X (DRX); luego, el mortero se mezcló con adiciones de nano-TiO2 (0.0, 0.5, 1.0, 3.0%) y DOWSILTM (0.0, 0.5%). Los morteros se sometieron a irradiación UV, para degradar el colorante orgánico rodamina B, monitoreando su variación de color usando un espectrofotómetro C I E L* a* b*.