Design of Low Tetnperature Hybrid TiO2 - Cyanuric acid nanocorrlposites - Application in the photodegradation of organic pollutants in water

Abstract

"the modification of Ti02 by cyanuric acid main reservoir of nitrogen opens the way to new hybrid nanomaterials with interesting photocatalytic activity. Indeed, this work can be summed up in two main objectives. The first concerns the development of titanium dioxide nanohybrid materials decorated with cyanuric acid and obtained at low temperature thanks to the use of growth catalyst. The second objective is to evaluate these different nanomaterials in the photodegradation of formic acid under UV irradiation and methyl orange under visible light. Thus, elaboration parameters have been varied in order to understand the behavior of each nanomaterial towards the photodegradation of formic acid and methyl 2OTi-Interesting textural and structural properties of cyanuric acidorange. nanohybrid materials have been noted. BET analysis shows high surface area. X-ray and Raman spectroscopy show successful formation of anatase phase at low temperature without performing any post-thermal treatment. This finding, open-up new routes for nanohybrid materials. The photoluminescence analysis shows clearly the benefit effect of nitrogen . 2quenching. IR analysis shows CA grafting onto TiOPL and results in which are ascribed 1 -and 1400 cm1 -cm815 We observed elongations at to triazine and C- N in conjugated molecule. However, UV-visible in reflectance mode showed unexpected shift of band gaps to higher energy absence of values. This is surprising result. and can be explained by the tion roducIn addition, the p. 2nitrogen insertion in the lattice of TiOmethod and the content of functionalized cyanuric acid (CA) have been investigated, thus leading to the development of nanomaterials revealing interesting photocatalytic properties, compared to their undoped counterparts. Thus, a content of 5% by mass of functionalized CA leads to a maximum activity. These results also showed that the maximum photocatalytic activity is reached for a content corresponding to a hybrid maximum recovery by formic acid monolayer on the surface of etween the textural properties, the structural ion b. Thus, a correlat2TiOvisible and IR) and the -Raman, photoluminescence, UVray, -(Xproperties degradation rate constant of FA has been established using Langmuir-by cyanuric acid 2 TiOmodification of Hinshelwood model. Indeed, the positively influence their intrinsic performance photodegradation of in the formic acid. The addition of CA stabilizes the holes and facilitates the transfer of photogenerated electrons leading to better charge separation. Thus, the photocatalytic activity is significantly improved by limiting the recombination probability of the photogenerated electron-hole pairs. nanohybrids were explored for the 2 TiO-Finally, cyanuricphotodegradation of methyl orange (MO) under visible light in presence of excess of diluted oxygen peroxide. Our results show a pseudo-first order rate degradation of MO molecules. Again, the photocatalytic activity is significantly improved in presence of 5wt% cyanuric acid."