Decomposition of 2-naphthol in water by TiO2 modified with MnO and CeO

Decomposition of 2-naphthol in water by TiO₂ modified with SnO<i>_x</i> or (Mn, Sn)O<i>_x</i> and MnO<i>_x</i>

“…We confirmed that the valence band (VB) top decreases (becomes negative) concomitantly with increases in the MnO x amount. 12) This trend was confirmed for TiO 2 modified with transition metal oxide clusters by the CCC process, suggesting the forma- Figure 5 presents the concentration changes of 2-naphthol in water at 50°C in the dark. Pure TiO 2 , Sn2 and (MnSn)2 exhibited almost no concentration change during 6 h, except during the initial 1 h. However, decreased concentration of 2-naphthol after 1 h was observed clearly for Mn3, Sn2Mn3, and (Mn,Sn)2Mn3.…”

“…A similar trend was reported for Mn3 in our previous study, and was attributed to the slow re-oxidation rate of the reduced MnO x by dissolved oxygen during the MvK mechanism in water. 12) When UV light was illuminated onto the samples in the dark after (MnSn)2Mn3 was used twice, the decomposition activity recovered. That recovery became remarkable when heat treatment at 300°C was applied.…”

“…8),10),11) Very recently, we modified a TiO 2 surface with MnO x by chemisorption calcination cycle (CCC) processing. 12) The decomposition activities of the materials on 2-naphthol were evaluated in water at 50°C with and without visible light illumination. Both the decomposition activity in the dark and the visible light photocatalytic activity were induced in TiO 2 by modification with MnO x .…”

Decomposition of 2-naphthol in water and antibacterial property by NiO and CeO<i>_x</i> modified TiO₂ in the dark or under visible light

“…Recently, Shiohara et al modified rutile-type TiO 2 with MnO x and CeO y clusters using chemisorption calcination cycle (CCC) method 12), 13) developed by Tada et al They demonstrated that this material possesses decomposition activity against 2naphthol in water, either in the dark or under visible light at 50°C. 14) They attributed the activity in the dark to the Marsvan Krevelen (MvK) mechanism 15)17) of MnO x and CeO y . The activity under visible light was attributed to the apparent bandgap decrease caused by the formation of a TiOMn interfacial bond yielding a surface d sub-band, which disperses around the energy level to overlap with the valence band (VB) of TiO 2 .…”

“…We additionally modified CeO x onto the surface of the material using the same method. Then decomposition activity against 2-naphthol was evaluated in the dark and also under visible light under the same conditions as those used for the work conducted by Shiohara et al 14) .We also evaluated the antibacterial activity of prepared NiO-modified TiO 2 under visible light. Bacteria are classified into two categories: gram-negative bacteria and gram-positive bacteria.…”