학술논문

Low-temperature strategy for vapor phase hydrothermal synthesis of C\N\S-doped TiO2 nanorod arrays with enhanced photoelectrochemical and photocatalytic activity
Document Type
Article
Source
Journal of Industrial and Engineering Chemistry, 98(0), pp.130-139 Jun, 2021
Subject
화학공학
Language
English
ISSN
1876-794X
1226-086X
Abstract
In this study, a material with high photocatalytic activity was synthesized using ternary C/N/S-dopedTiO2 nanorod array (TiO2); this was done using a practical and straightforward vapor-phase hydrothermal(VPH) method at a low temperature. The effect of C/N/S content on TiO2 morphology, optical,photocatalytic and photoelectrochemical (PCE) properties of the material was investigated by varying thequality of thiourea. C/N/S-TiO2 reduced the bonding rate of electron-hole pairs and enhances visible lightabsorption, photocatalytic, and PCE properties. The C/N/S doping could significantly adjust theabsorption cut-off wavelengths (407 602 nm) and shorten the bandgap (3.04 2.18 eV) of TiO2. Undersimulated sunlight, 8-C/N/S-TiO2 had the highest photocatalytic efficiency of 97.6% for methylene blue(MB) in 150 min with a rate constant of 0.0192 min 1, which is approximately four times that of TiO2(0.005 min 1). The 8-C/N/S-TiO2 photoelectrode had the lowest transfer resistance for interfacial chargesand highest transient photocurrent of 33.5 mA/cm2, which isfive times higher than that of TiO2 (6.6 mA/cm2). The 8-C/N/S-TiO2 exhibits the most extensive PCE behavior as a photoelectrode, and has a currentdensity of 38.2 mA/cm2 at 2.5VRHE, which is about two times higher than TiO2 (19.1 mA/cm2). Thefavorable sunlight-driven photocatalytic activity is probably due to the synergistic effect of C/N/S-doping,which shifts the valence band maximum of TiO2 upward. This provides new ideas for future solar cellsthat can use dye-sensitized TiO2 nanorod arrays as photoanodes. It is noteworthy that VPH is a veryeffective strategy for fabricating semiconductors doped with multiple nonmetallic elements.