One-step formation of TiO₂hollow spheres via a facile microwave-assisted process for photocatalytic activity

Abstract

Mesoporous TiO hollow spherical nanostructures with high surface areas were successfully prepared using a microwave method. The prepared hollow spheres had a size range between 200 and 500 nm. The spheres consisted of numerous smaller TiO nanoparticles with an average diameter of 8 nm. The particles had an essentially mesoporous structure, with a pore size in the range of 2-50 nm. The results confirmed that the synthesised of anatase TiO nanoparticles with specific surface area approximately 172.3 m g. The effect of ultraviolet and visible light irradiation and catalyst dosage on the TiO photocatalytic activity was studied by measuring the degradation rate of methylene blue. The maximum dye degradation performances with low catalyst loading (30 mg) were 99% and 63.4% using the same duration of ultraviolet and visible light irradiation, respectively (120 min).

Titanium Dioxide Microscale and Macroscale Structures: A Mini-Review

“…In contrast to the two above-noted synthesis strategies, the self-templating method has attracted interest due to its lower production cost and feasibility for scaling up to the industrial scale. Ostwald ripening is attributed in some papers to the mechanism of the growth of TiO 2 spheres and hollow spheres [80,81]. Ostwald ripening is a thermodynamic process that is tailored by the differences in Gibbs energy (∆G) between the high G of the precursor and the low G of the resultant hollow nanostructure.…”

“…In comparison with the conventional methods, which localize overheating output from the hot surface of the reaction vessels, possibly leading to product composition changes in cases of heating for elongated periods, the microwave method takes advantage of the potential to produce uniform internal heating by direct coupling of microwave energy with the polar molecules present in the reaction mixture [81]. In order to produce TiO 2 hollow spheres, Alosfur et al (2018) recently utilized a 100 mL solution of titanium (IV) isopropoxide (TTIP 0.2 M; 95% ethanol) placed in a microwave oven with a reflux device and magnetic stirrers at 550 W for 5 min.…”

“…The growth mechanism of the TiO 2 hollow spheres was attributed to the Ostwald ripening process during heating. The photocatalytic activity of the TiO 2 hollow spheres for MB was high under both UV and visible light irradiation; this was attributed to the organization of the NPs into a hierarchical structure that can prevent random aggregation [81].…”

Facile synthesis of C, N-TiO2 nanorods via layered Ti 3 O 7 2 − -TMAH interlaminar bonding interaction and their enhanced catalytic performance

“…Photocatalysis has been widely employed as a green, non-secondary wastewater agent especially for dyeing wastewater treatment [5][6][7][8][9]. Photocatalytic nanomaterials have excellent degradation performance due to their high specific surface area [10][11][12]. In particular, TiO 2 nanomaterials appear to be a promising green catalyst due to its environmental safety, low cost and no secondary pollution [13][14][15][16].…”

Fabrication of Ag/AgBr/Ag3VO4 composites with high visible light photocatalytic performance

“…[9][10][11] To date, the most commonly used photocatalyst is TiO 2 that has excellent chemical stability and is abundant, non-toxic, and low-cost. 12,13 However, TiO 2 is a photocatalyst with a wide band gap (3.2 eV), and its low solar energy utilization and quantum yield limit its practical application. [14][15][16] Researchers have tried to develop a variety of photocatalytic materials with effective visible light responses, which has already been a key problem in the eld of photocatalysis.…”