Nanomaterials in geopolymer composites: A review

Development of an Antimicrobial Inorganic Polymer Based on Fly Ash and Metakaolin Incorporated by Nano-TiO 2 for Reactive Dye Removal

“…4, the absorption band in the range of 1415-1456 cm -1 was formed as a result of the carbonation of calcium hydroxide. It appeared in the FTIR spectrum of the FM composite and completely disappeared in the FM-TiO2 mix, which may be attributed to the inter diffusion of NT particles inside open pores of geopolymer composites and inhibited the carbonation of hydration products [49]. For both geopolymer composites, the FTIR spectra show absorption bands in the ranges of 1639-1648 cm -1 that are connected to the bending vibration modes of the H-O-H group.…”

“…Furthermore, the presence of Ti-O-Ti photosensitive species was linked to the band's appearance at approximately 704 cm -1 in FM-TiO2 geopolymer [49]. Another indicator of NT particle dispersion inside the geopolymer matrix was the band of the O-Si-O bending vibration appearing for FM-TiO2 at 453-458 cm -1 [49,56]. On the other hand, Figure 4 shows that after degradation by sunlight, the asymmetric stretching vibration of the Si-O-T band in the FM and FM-TiO2 composites containing reactive blue 19 dye effluent shifts to higher wave numbers of 988 and 995 cm -1 , respectively.…”

“…In comparison to pure geopolymer composite (FM), geopolymers with nano-TiO2 added (FM-TiO2) demonstrated greater mechanical strength. After 28 days of hydration and during the extended hydration period, the incorporation of nano-TiO2 accelerated the polymerization process and enhanced the compressive strength of the composite [49]. The geopolymer composite MF-TiO2 attained its maximum compressive strength value (65 MPa) after 28 days of hydration.…”

“…As we observed from Figure 4 the incorporation of NT inside the geopolymer retards the hydration process with time, as indicated by a decrease in the intensity of the asymmetric stretching vibrations of Si-O-T at 962 cm -1 for the FM-TiO2 mix after 28 days compared with the reference sample FM. These may be related to the presence of NT decreasing the number of pores on the surface of the geopolymer composite, which affects the geopolymerization process [49]. Furthermore, the presence of Ti-O-Ti photosensitive species was linked to the band's appearance at approximately 704 cm -1 in FM-TiO2 geopolymer [49].…”

“…These may be related to the presence of NT decreasing the number of pores on the surface of the geopolymer composite, which affects the geopolymerization process [49]. Furthermore, the presence of Ti-O-Ti photosensitive species was linked to the band's appearance at approximately 704 cm -1 in FM-TiO2 geopolymer [49]. Another indicator of NT particle dispersion inside the geopolymer matrix was the band of the O-Si-O bending vibration appearing for FM-TiO2 at 453-458 cm -1 [49,56].…”