Ti³⁺ Self-Doped Blue TiO₂(B) Single-Crystalline Nanorods for Efficient Solar-Driven Photocatalytic Performance

Abstract

Ti self-doped blue TiO(B) single-crystalline nanorods (b-TR) are fabricated via a simple sol-gelation method, cooperated with hydro-thermal treatment and subsequent in situ treatment method, and afterward annealed at 350 °C in Ar. The structures are characterized by X-ray diffraction (XRD), Raman, X-ray photoelectron spectroscopy (XPS), diffuse reflectance spectroscopy (UV-vis), scanning electron microscopy (SEM), and transmission electron microscopy (TEM). The prepared b-TR with narrow band gap possesses single-crystalline TiO(B) phase, Ti self-doping, and one-dimensional (1D) rodlike nanostructure. In addition, the improved photocatalytic performance is studied by decomposition of Rhodamine B (RhB) and hydrogen evolution. The degradation rate of RhB by Ti self-doped blue TiO(B) single-crystalline nanorods is ∼6.9- and 2.1-times higher compared with the rates of titanium dioxide nanoparticles and pristine TiO(B) nanorods under visible light illumination, respectively. The hydrogen evolution rate of b-TR is 26.6 times higher compared with that of titanium dioxide nanoparticles under AM 1.5 irradiation. The enhanced photocatalytic performances arise from the synergetic action of the special TiO(B) phase, Ti self-doping, and the 1D rod-shaped single-crystalline nanostructure, favoring the visible light utilization and the separation and transportation of photogenerated charge carriers.

Preparation of Blue TiO2 for Visible-Light-Driven Photocatalysis

“…Blue TiO 2 (B) single-crystalline nanorods were obtained by further annealing at 350°C in Ar [33]. Under visible light illumination, the degradation rate of RhB reached 97.01% by b-TR and the photocatalytic hydrogen evolution rate was as high as 149.2 μmol h −1 g −1 under AM 1.5 irradiation [33].…”

“…Blue TiO 2 (B) single-crystalline nanorods were obtained by further annealing at 350°C in Ar [33]. Under visible light illumination, the degradation rate of RhB reached 97.01% by b-TR and the photocatalytic hydrogen evolution rate was as high as 149.2 μmol h −1 g −1 under AM 1.5 irradiation [33]. The mechanistic analysis and characterization results showed that the synergetic action of the special TiO 2 (B) phase, Ti 3+ self-doping, and the 1D rod-shaped single-crystalline nanostructure resulted in a narrowed bandgap of 2.61 eV, which enhanced the photocatalytic and photoelectrochemical performances [33] (Figure 10).…”

Design, Synthesis, and Structure-Property Relationships of Er3+-Doped TiO2 Luminescent Particles Synthesized by Sol-Gel

“…Indeed, the luminescence of Er 3+ ions at 1540 nm makes Er 3+ -doped TiO 2 systems suitable for optical planar waveguides, lasers, and fiber amplifiers for telecommunications [8,9,10,11]. In addition, red and green up-conversion emissions [12,13] make it a promising material for an even broader range of applications, such as photovoltaics, display technologies, medical diagnostics, and solid state lasers [14,15,16,17]. …”

“…The properties of a bulk material are significantly different with respect to the ones exhibited by the micro-/nano-particles [17,18,19]. Among the different synthesis methods employed for the fabrication of the TiO 2 particles, the sol-gel synthesis method has been demonstrated to allow a reliable and precise control of particle size and morphology [20,21,22,23].…”

Hydrothermal synthesis of In2O3 nanoparticles hybrid twins hexagonal disk ZnO heterostructures for enhanced photocatalytic activities and stability

“…However, ZnO with a wide band gap (Eg = 3.3 eV) can only be activated by ultraviolet (UV) light, which restricts its practical applications for solar energy [4–8]. Another main drawback of ZnO is rapid recombination of photo-induced electron-hole pairs, which results in the low quantum yield for any photocatalytic reactions [9–12]. Therefore, how to extend absorption edge of ZnO to visible light region for the utilization of about 43% solar spectrum meanwhile suppress the photo-generated electron-hole pairs recombination is still a great challenge for scientists.…”