WO3-modified TiO2 nanotubes for photocatalytic elimination of methylethylketone under UVA and solar light irradiation

Tungsten-based nanomaterials (WO 3 & Bi 2 WO 6 ): Modifications related to charge carrier transfer mechanisms and photocatalytic applications

“…The modification of WO 3 with TiO 2 improves the photoactivity in several ways: (i) recombination of charge carriers is lowered as W 6+ easily traps the electrons to form W 5+ ; (ii) oxygen vacancies on the TiO 2 surface will be covered by the dispersed WO 3 as a result of charge transfer, leading to high quantum efficiency; (iii) extends the range of excitation light to visible region; (iv) composite adsorbs more hydroxide ion or water molecules to generate hydroxyl radicals [127]; (v) WO 3 is nearly 15 times more acidic than TiO 2 and thus WO 3 coupling improves the surface acidity. The anatase has only Lewis acidity, while incorporation of WO 3 results in the appearance of Bronsted acidic sites.…”

“…Although, the charge transfer was prevailed in this composite, its deactivation during toulene degradation was noticed due to the accumulation of hydroxylated intermediates that are less reactive to free radicals [129]. The photocatalytic efficiency, CO 2 selectivity, carbon deficit, and deactivation of TiO 2 -WO 3 was linked to the activation wavelengths; highest activity of the composite suffered from strong The WO 3 -TiO 2 has been obtained by several methods like flame-spray pyrolysis [128a], spray drying method [128b], hydrothermal [127,131], ball milling [129], combined electrospinning-thermal evaporation [132], sol-gel [133] and evaporation-induced self-assembly (EISA) methods [134]. In the EISA process, WO 3 suppressed the anatase crystallization and favored the brookite nucleation.…”

“…This composite will be active at acidic pH and their performance deteriorated at alkaline medium for the degradation of DCP [135]. The ZPC of TiO 2 and WO 3 are at 6.4 and 0.3-0.5 respectively [127,128]. The heterocoupling of TiO 2 with WO 3 introduced more surface acidic groups shifting the isoelectric potential to a lower value than that of pure TiO 2 (~3.6).…”

Gas phase oxidation of n-decane and PCE by photocatalysis using an annular photoreactor packed with a monolithic catalytic bed coated with P25 and PC500

“…The most common photoreactors are tubular, annular and flat plate types [20][21][22]. Regarding the photocatalyst structural configuration, thin-film powder layer and/or fluidized bed [21,23], coated wall-parallel [24,25] and honeycomb/foam monolithic reactors [26][27][28] are probably the most representative.…”

A Novel Technique for the Deposition of Bismuth Tungstate onto Titania Nanoparticulates for Enhancing the Visible Light Photocatalytic Activity

“…Thus, titanium dioxide coupled with such materials, as CdS [5], WO 3 [6], Cu 2 O [7], etc has been reported. Bismuth tungstate (Bi 2 WO 6 ) is gaining increasing popularity as a narrow band gap semiconductor that exhibits good photocatalytic properties under visible light irradiation [8,9].…”