Effect of Surface Treatment on the Selective Photocatalytic Oxidation of Benzyl Alcohol into Benzaldehyde by O2 on TiO2 Under Visible Light

Abstract

The photocatalytic oxidation of benzyl alcohol into benzaldehyde proceeded with high conversion and selectivity on a TiO 2 photocatalyst by O 2 under visible light irradiation. Surface complex formed by the interaction of benzyl alcohol with the Ti sites and/or surface OH groups of TiO 2 play an important role in the absorption of visible light and unique selective photocatalytic reaction.

Photocatalysis of titanium dioxide modified by catechol-type interfacial surface complexes (ISC) with different substituted groups

“…Therefore, the development of visible-light-sensitive TiO 2 photocatalyst has been a great concern for efficient utilization of solar light [6][7][8][9]. Visible-light-responsive TiO 2 photocatalysts have been designed by several methods such as doping with nitrogen and other elements [10][11][12][13][14], organic dye sensitizer [15], plasmonic Au and Ag nanoparticles [16][17][18][19], and interfacial surface complexes (ISC) [20][21][22][23][24][25][26][27][28][29][30].…”

“…Recently, attention has been paid to photocatalysis due to the ISC formed by the interaction of TiO 2 surface with such colorless organic compounds as aromatic alcohols [20][21][22][23][24][25], amine [26,27], and phenolic compounds [28][29][30]. We previously reported the selective photocatalytic oxidation of benzyl alcohol into benzaldehyde with high selectivity on TiO 2 under visible-light irradiation [20][21][22][23][24] and theoretical studies on its reaction mechanisms by DFT calculations [25].…”

“…We previously reported the selective photocatalytic oxidation of benzyl alcohol into benzaldehyde with high selectivity on TiO 2 under visible-light irradiation [20][21][22][23][24] and theoretical studies on its reaction mechanisms by DFT calculations [25]. The visible-light response of the ISC formed by the interaction of benzyl alcohol with the TiO 2 surface is attributed to excitation from the donor levels in the TiO 2 midband, and the ISC is selectively converted into benzaldehyde.…”

DFT study on the reaction mechanisms behind the catalytic oxidation of benzyl alcohol into benzaldehyde by O2 over anatase TiO2 surfaces with hydroxyl groups: Role of visible-light irradiation

“…Hence, the selective photocatalytic oxidation of alcohols by O 2 under UV-light and/or visible-light irradiation on such photocatalyst as pure TiO 2 [8][9][10][11][12][13][14], dye-sensitized TiO 2 [15], gold nano-particles supported TiO 2 or CeO 2 [16,17], Fe 3+ or Rh 3+ ions modified TiO 2 [18,19], nitrogendoped TiO 2 [20], Nb 2 O 5 [21,22] and carbon nitride (C 3 N 4 ) [23] have been widely studied.…”

An evaluation of the application of a TiO2/ Cu(II)/solar simulated radiation system for selective oxidation of benzyl alcohol derivatives

“…Augugliaro et al performed the selective photocatalytic oxidation of benzyl alcohol in pure water by using different TiO 2 samples, obtaining selectivities to benzaldehyde up to 38%. Higashimoto et al reported the selective photocatalytic oxidation of benzyl alcohol to benzaldehyde with conversion and selectivity higher than 99% on TiO 2 in the presence of O 2 under visible light irradiation using acetonitrile as solvent. Feng and co‐authors have shown that the photocatalytic selective oxidation of benzyl alcohol can be achieved over transition metal‐modified TiO 2 in the presence of molecular oxygen in a solvent free system and under ultraviolet irradiation.…”