Effect of the TiO2 doped photocatalytic nano-additives on the hydration and microstructure of Portland and High Alumina Cements
Palabras clave : 
Cement
Alumina cement
Nano-additives
Doped TiO2
SEM
Calorimetry
Hydration
Fecha incorporación: 
14-oct-2017
Editorial : 
MDPI AG
ISSN: 
2079-4991
Nota de editorial: 
From the January 2016 issue, MDPI journals will use article numbers in place of the traditional method of continuous pagination through the volume. This step helps us to maintain a rapid, efficient production process by being able to define pagination as soon as a paper is accepted. We have recently made a number of improvements to article layout and production procedures, of which article numbers is just one component. You can read more about the changes at http://blog.mdpi.com/2015/12/01/a-new-look-for-mdpi-papers/. For papers that use article numbers the page number will start from 1 and the citation needs only list the article number, e.g., Holmes, L.; LaHurd, A.; Wasson, E.; McClarin, L.; Dabney, K. Racial and Ethnic Heterogeneity in the Association Between Total Cholesterol and Pediatric Obesity. Int. J. Environ. Res. Public Health 2016, 13, 19 (article number: 19. http://www.mdpi.com/1660-4601/13/1/19).
Nota: 
Creative Commons Attribution License 4.0
Cita: 
Pérez-Nicolás M, Navarro-Blasco I, Fernández JM, Álvarez JI, "Effect of the TiO2 doped photocatalytic nano-additives on the hydration and microstructure of Portland and High Alumina Cements", Nanomaterials 2017, 7(10), 329
Resumen
Mortars with two different binders (Portland cement (PC) and high alumina cement (HAC)) were modified upon the bulk incorporation of nano-structured photocatalytic additives (bare TiO2, and TiO2 doped with either iron (Fe-TiO2) or vanadium (V-TiO2)). Plastic and hardened state properties of these mortars were assessed in order to study the influence of these nano-additives. Water demand was increased, slightly by bare TiO2 and Fe-TiO2, and strongly by V-TiO2, in agreement with the reduction of the particle size and the tendency to agglomerate. Isothermal calorimetry showed that hydration of the cementitious matrices was accelerated due to additional nucleation sites offered by the nano-additives. TiO2 and doped TiO2 did not show pozzolanic reactivity in the binding systems. Changes in the pore size distribution, mainly the filler effect of the nano-additives, accounted for the increase in compressive strengths measured for HAC mortars. A complex microstructure was seen in calcium aluminate cement mortars, strongly dependent on the curing conditions. Fe-TiO2 was found to be homogeneously distributed whereas the tendency of V-TiO2 to agglomerate was evidenced by elemental distribution maps. Water absorption capacity was not affected by the nano-additive incorporation in HAC mortars, which is a favourable feature for the application of these mortars.

Ficheros en este registro:
Fichero: 
nanomaterials-07-00329.pdf
Descripción: 
Tamaño: 
6,21 MB
Formato: 
Adobe PDF


Los ítems de Dadun están protegidos por copyright, con todos los derechos reservados, a menos que se indique lo contrario.