Enhancement of TiO2 NPs Activity by Fe3O4 Nano-Seeds for Removal of Organic Pollutants in Water

Abstract

The enhancement of the photocatalytic activity of TiO2 nanoparticles (NPs), synthesized in the presence of a very small amount of magnetite (Fe3O4) nanoparticles, is here presented and discussed. From X-ray diffraction (XRD) and differential scanning calorimetry (DSC) analyses, the crystallinity of TiO2 nanoparticles (NPs) seems to be affected by Fe3O4, acting as nano-seeds to improve the tetragonal TiO2 anatase structure with respect to the amorphous one. Photocatalytic activity data, i.e., the degradation of methylene blue and the Ofloxacin fluoroquinolone emerging pollutant, give evidence that the increased crystalline structure of the NPs, even if correlated to a reduced surface to mass ratio (with respect to commercial TiO2 NPs), enhances the performance of this type of catalyst. The achievement of a relatively well-defined crystal structure at low temperatures (Tmax = 150 °C), preventing the sintering of the TiO2 NPs and, thus, preserving the high density of active sites, seems to be the keystone to understand the obtained results.

Tunable Pseudocapacitance in 3D TiO2−δ Nanomembranes Enabling Superior Lithium Storage Performance

“…Another sharp exothermic peak around 306 °C with no weight loss corresponds to the phase transition from amorphous to the tetragonal anatase structure. 1 Subsequently, a big weight loss (42.897%) can be observed from 300 to 550 °C, corresponding to the thermal decomposition of photoresist. If we exclude the mass of photoresist, the minimum amount of oxygen deficiencies in TiO 2-δ is calculated to be 5.31%.…”

Synthesis of Magnetic Microspheres with Sodium Alginate and Activated Carbon for Removal of Methylene Blue

“…These results indicated that magnetite (Fe 3 O 4 ) has a face-centered cubic structure. Moreover, we did not observe other iron oxides, such as α-Fe 2 O 3 , β-Fe 2 O 3 , γ-Fe 2 O 3 , which suggests that Fe 3 O 4 was not oxidized to other forms in the synthetic steps [24,25,32]. …”

“…Characteristic peaks at 1070, 1620 and 3416 cm −1 are caused by –OH stretching vibration, 1430 cm −1 is attributed to –CH 2 – stretching vibration [20,25]. Compared to the spectra of AC and SA, the new band at 564 cm −1 can be attributed to the stretching vibrations of Fe–O in MSA-AC2, and the enhanced peaks 3416 cm −1 and 1620 cm −1 indicate the presence of Fe 3 O 4 .…”

“…Fe 3 O 4 , as a magnetic material, has gained much attention as a means to provide fast and efficient adsorption [5,24,25]. Yang et al [26] prepared Fe 3 O 4 /histidine composite nanoclusters, which exhibited remarkably efficient adsorption of proteins.…”

Making Marble Powder Waste Profitable by Using Nano-TiO2 Surface Modification for Air Quality Improvement Applications

“…To assess the degradation efficiency of hazardous organics by the prepared nano-TiO 2 by way of its photocatalytic activity, a methylene blue degradation test was carried out according to the standard of ISO 10678:2010 [22][23][24][25]. Firstly, 0.4 mg methylene blue powder was dissolved sufficiently into 100 ml deionized water, followed by adding 12.5 mg asprepared TiO 2 nanoparticles into the solution.…”