Photocatalytic reduction of nitrate in seawater using C/TiO2 nanoparticles

Photocatalytic Reduction of Hexavalent Chromium with Nanosized TiO2 in Presence of Formic Acid

“…Because of the presence of formic acid, the hydroxyl radical (•OH), which is produced from the holes and OH − , is able to be captured by formic acid. This will produce reactive •CO2 − , which has a relatively negative redox potential, E 0 (•CO2 − /CO2) = −1.9 V vs. NHE [24,25], compared with the redox potential for Cr(VI), E 0 (HCrO4 − /Cr 3+ ) = 1.35 V vs. NHE [26]. TiO2 + hν → TiO2 (eCB − + hVB + )…”

Enhanced Solar Photocatalytic Reduction of Hexavalent Chromium in Seawater over Carbon Doped TiO2 Nanoparticles

“…Additionally, no glycine was added, to avoid any probability for carbon incorporation. Details on the preparation and characterization procedures have been described in our previous work (Shaban et al, 2016).…”

“…Whereas after the same irradiation time, only 42.3 % of the same concentration of Cr(VI) was removed using pure TiO 2 under the same experimental conditions. The observed enhanced photocatalytic activity of CTiO 2 nanoparticles, can be attributed to carbon modification of TiO 2 (Khan et al, 2002;Shaban et al, 2013;Shaban et al, 2016;Shaban and Khan, 2008;Xu et al, 2006). The origin of visible-light response of carbon doped TiO 2 is due to the presence of the dopant carbons at the oxygen sites of TiO 2 and the formation of C 2p states above the valence band which can be mixed with the O 2p valence band, leading to a significant narrowing of the optical bandgap energy of CTiO 2 (Irie et al, 2006).…”

“…Therefore, the extension of its utilization over the main part (45%) of visible region in solar spectrum is of crucial importance. Many efforts have been devoted to reduce its optical band gap energy through different approaches such as doping with metals (Anpo et al, 1997;Al-Azri et al, 2015;, and non-metal ions (Asahi et al, 2001;Khan et al, 2002;Shaban et al, 2013;Shaban et al, 2016;Umebayashi et al, 2002). In particular, modification of TiO 2 via carbon incorporation has been evidenced as an effective approach to enhance its photocatalytic performance under visible light (Fang et al, 2016;Khan et al, 2002;Liu, et al, 2016;Shaban et al, 2013;Shaban et al, 2016).…”

Design of inner-motile ZnO@TiO2 mushroom arrays on magnetic cilia film with enhanced photocatalytic performance

“…Among copious photocatalysts [10][11][12][13], titanium dioxide (TiO 2 ) has become the most commonly used one due to its superior photocatalytic activity, chemical stability, nontoxicity and low cost [14][15][16]. However, numerous studies devoted to improve the photocatalytic activity of TiO 2 in slurry systems [17][18][19][20][21]. Although the traditional TiO 2 powders benefit from fast mass transfer, the absorption and scattering caused by nanoparticles lead to a nonuniform distribution of light and thus low photon transfer.…”