Photocatalytic Activity and RNO Dye Degradation of Nitrogen-doped TiO2 Prepared by Ionothermal Synthesis

Abstract

This work concerns the preparation a nitrogen-doped TiO 2 by ionothermal synthesis methods and the photocatalytic studies. In this procedure, alkoxide was used as a titanium source, and a deep eutectic mixture of choline chloride and urea (molar ratio 1:2) served as a solvent and source of nitrogen. Different samples were synthesized varying the percentages of the eutectic mixture, titanium butoxide, and water, as well as temperature and reaction time. The catalysts were characterized by X-ray diffraction, Raman spectrometry, scanning electron microscopy, and diffuse reflectance spectroscopy. N-doping was confirmed by X-ray photoelectron spectroscopy. The photocatalytic activity of the N-TiO 2 nanoparticles was evaluated in the oxidation of N,N-dimethyl-4-nitrosoaniline (RNO) dye. The best photocatalytic activity under illumination by UV and visible light was found for the catalysts prepared under reflux in the presence of water, and for the catalysts prepared hydrothermally using intermediate percentages of the nitrogen source (the eutectic mixture).

Visible-light photocatalytic activity and recyclability of N-doped TiO2 films grown by MOCVD

“…The narrowing of the TiO 2 band gap region can be obtained by metallic (Ag, Cu, Ni, Fe, Ru) and non-metallic (S, N, C, B, P) species [25,26], from the formation of intermediate states. Other studies also have shown the possibility of using doped-TiO 2 for the degradation of different dyes, such as reactive triazine dyes (Yellow 84, Red 120, Blue 160) [27], N,Ndimethyl-4-nitrosoaniline (RNO) [28], tartrazine (TRZ), Eriochrome Black-T (EBT) [29], Rhodamine B (RhB) [30], and principally methyl orange dye and methylene blue [31]. Maria Magdalane et al [32,33] studied the catalytic properties of the CeO 2 /Er 2 O 3 and CeO 2 /La 2 O 3 based binary metal oxide nanostructures on the RhB photodegradation under visible light.…”

Obtaining Porous Zinc Oxide Ceramics Using Replica Technique: Application in Photocatalysis

“…These are responsible for the mineralization of the organic components 6-8. Semiconductors are generally studied in the form of ultrafine powders due to their larger surface area. This characteristic enables greater exposure to oxidizing sites and favors photocatalysis 3,8,[16][17][18] . Nevertheless, for daily use in dye photocatalysis, it is necessary to use porous solid ceramics, which have larger surface areas than dense solids, since the material in particulate form (powders) is difficult to be recovered, compromising its regular use 18 .…”

The Influence of pH on the Nitrogen-doped TiO2 Structure and Its Photocatalytic Activity on Methylene Blue Degradation

“…Synthesis N-doped TiO2 have been widely studied, mainly prepared using annealing of TiO2 under nitrogen atmosphere (Ryoji Asahi et al, 2014;Irie et al, 2003) and chemical proses with aqua-based such as sol-gel method (Caratto et al, 2012;Qiu and Burda, 2007;Shang et al, 2014), hydrothermal (Zhou et al, 2011), ionothermal (Pipi et al, 2017) or solvothermal (Dunnill et al, 2011). The sol-gel method is being the simple technology that does not require other nitrogen source like ammonia (Gao et al, 2014) and also it is easily controlling structure, morphology, and particle size by simple variations of synthesis parameters, such as solution pH, reactant composition, temperature, and solvent systems (Reddy et al, 2015).…”