Photocatalytic properties, mechanical strength and durability of TiO2/cement composites prepared by a spraying method for removal of organic pollutants

Development of Photocatalytic 3D-Printed Cementitious Mortars: Influence of the Curing, Spraying Time Gaps and TiO2 Coating Rates

“…Semiconductor photocatalytic materials are able to catalyze the mineralization process of organic and inorganic compounds [3,11]. Titanium dioxide (TiO 2 ) holds particular features, such as high chemical stability, high oxidation-reduction capacity, non-toxicity, and is available at a lower price, besides being the most employed semiconductor in photocatalytic materials [2,3,8,[12][13][14][15][16][17]. TiO 2 is widely used in different fields for the purpose of water and air purification and self-cleaning [2,[18][19][20][21], including in civil engineering for cementitious materials (by, e.g., [3][4][5]7,17,[22][23][24][25]).…”

“…Titanium dioxide (TiO 2 ) holds particular features, such as high chemical stability, high oxidation-reduction capacity, non-toxicity, and is available at a lower price, besides being the most employed semiconductor in photocatalytic materials [2,3,8,[12][13][14][15][16][17]. TiO 2 is widely used in different fields for the purpose of water and air purification and self-cleaning [2,[18][19][20][21], including in civil engineering for cementitious materials (by, e.g., [3][4][5]7,17,[22][23][24][25]). The main factors that allow the cementitious materials an ideal support medium for semiconductors (and in particular TiO 2 ) are: (i) the porous structure of the cementitious mortar/concrete bulk [4,9,24]; (ii) the strong binding ability of the cementitious materials [9,17]; as well as (iii) the compatibility between TiO 2 particles with the alkaline nature of cementitious materials [6,9].…”

“…Different methodologies have been used to apply semiconductors into cementitious composites, in order to endow them photocatalytic properties [24]. Volume incorporation during the mixing process (by, e.g., [3,5,22,23]), binder modification [4,15], using the catalytic carrier in the cementitious mixture [24,25], and surface coating by spraying semiconductor particles (by, e.g., [3,5,17,24,26,27]) are some methods used for the photocatalytic functionalization. The coating method by spraying semiconductor particles is recognized as the most efficient and easiest application method for using semiconductors compared to other approaches [17,24].…”

“…Volume incorporation during the mixing process (by, e.g., [3,5,22,23]), binder modification [4,15], using the catalytic carrier in the cementitious mixture [24,25], and surface coating by spraying semiconductor particles (by, e.g., [3,5,17,24,26,27]) are some methods used for the photocatalytic functionalization. The coating method by spraying semiconductor particles is recognized as the most efficient and easiest application method for using semiconductors compared to other approaches [17,24]. In the case of adding semiconductors into the mixture composition, it is reported that higher amounts of semiconductors must be used to have the same distribution of TiO 2 particles on the specimens' surface when compared to the surface coating method [5].…”

Photocatalytic Performance of Alkaline Activated Graphitic Carbon Nitride Under Blue LED Light

“…Photocatalytic materials are the core part of photocatalytic technology. Currently, TiO2, ZnO and other photocatalysts are widely used [4,5]. However, these metalcontaining photocatalysts are difficult to recover, and will cause harm to the ecosystem if they enter water.…”