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(a) Fourier transform infrared (FT-IR) spectra and (b) Photoluminescence (PL) emission spectra of as-prepared F-TiO 2 and OH-TiO 2 samples.
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In this study, we completed a simple low-temperature synthesis of nest-like titanium oxide (TiO2) microspheres with exposed (001) facets. For the first time, the photocatalytic performance was enhanced by sodium hydroxide (NaOH) alkalization. The characterization of as-synthesized F-TiO2 and OH-TiO2 were analyzed by field emission scanning electron...
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... Fourier transform infrared (FT-IR) spectroscopy was employed to investigate the chemical bonding of the catalysts (Figure 5a). The absorption peaks of F-TiO2 and OH-TiO2 were observed at 3416 cm −1 and 1630 cm −1 , respectively, which could be assigned to the adsorbed and bound H2O on the particles, respectively [38][39][40]. ...
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... Fourier transform infrared (FT-IR) spectroscopy was employed to investigate the chemical bonding of the catalysts (Figure 5a). The absorption peaks of F-TiO2 and OH-TiO2 were observed at 3416 cm −1 and 1630 cm −1 , respectively, which could be assigned to the adsorbed and bound H2O on the particles, respectively [38][39][40]. ...
Context 3
... Fourier transform infrared (FT-IR) spectroscopy was employed to investigate the chemical bonding of the catalysts (Figure 5a). The absorption peaks of F-TiO 2 and OH-TiO 2 were observed at 3416 cm −1 and 1630 cm −1 , respectively, which could be assigned to the adsorbed and bound H 2 O on the particles, respectively [38][39][40] ...
Context 4
... Photoluminescence (PL) emission spectra were used to investigate the efficiency of charge carrier trapping, immigration and transfer, and to understand the fate of electron hole pairs in catalysts (Figure 5b). Six peaks were observed in the spectra. ...
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Citations
... [50]. In the TiO2/HTiOF3, the diffraction peak of TiO2 is much sharper than that of pure TiO2, which is attributed to the increase of crystallinity of TiO2 particles due to the addition of F [51]. ...
In order to solve the problem of tetracycline hydrochloride (TCH) wastewater pollution, a photocatalyst for the efficient utilization of sunlight was proposed. In this work, a new method for the synthesis of three-dimensional flower-like Ag/TiO2-{001}/HTiOF3 photocatalyst was applied, where surface oxygen vacancies can induce Ag nanoparticles (NPs) to disperse on the surface of the photocatalyst, which avoids the aggregation of Ag NPs into large particles. The appropriate mesoporous structure of the photocatalyst makes TCH have a stronger affinity on its surface, which is more conducive to the subsequent photodegradation. Furthermore, the surface plasmon resonance (SPR) of Ag NPs extends the response region of photocatalyst to visible light, and the heterojunction formed with TiO2/HTiOF3 further stimulates the electrons in the oxygen vacancy region and inhibits the recombination of carriers. 10-Ag/TiO2/HTiOF3 showed the best degradation activity (96%) for TCH when the ratio of Ag and TiO2-{001}/HTiOF3 was 10%. In addition, the Ag/TiO2-{001}/HTiOF3 photocatalyst has excellent photocatalytic activity, structural stability and sedimentation performance. The prepared catalyst has practical application prospect.
... The peak~400 nm is ascribed to bound exciton emission due to the trapping of free excitons by titanate groups near defects. Reason for this emission signal is due to metal-ligand charge transfer from Ti 3+ to oxygen anion in TiO 6 complex [58][59][60]. The emission peak at 438 nm is assigned to the oxygen vacancies or defect states in the TiO 2 NPs [61]. ...
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Photocatalysis is still a promising technology to alleviate the antibiotic residual problem of wastewater in the ecological environment. Herein, an all-solid-state Z-scheme [email protected]3PO4/TiO2-(F2) (TFAP) heterojunction photocatalyst was constructed using the hydrothermal method for the first time. The photocatalytic performance of TFAP nanocomposites for tetracycline hydrochloride (TCH) degradation was evaluated under simulated sunlight. The prepared materials were characterized by XRD, FE-SEM, TEM, BET, FT-IR, UVvis DRS, XPS, PL, and ESR measurements. The TFAP nanocomposites showed high degradation efficiency and excellent repeatability to TCH destruction. Among them, the (TFAP 1-1) nanocomposite has a lower bandgap energy (1.80 eV), a larger specific surface area (53.48 m²/g), and a lower electron-hole recombination rate. After 2.5 h of simulated sunlight irradiation, the degradation rate of the 200 mg/L (TFAP 1-1) nanocomposite (k=0.0154 min⁻¹) to 10 mg/L TCH reached 94.14%, which was much higher than that of the pure TiO2, TiOF2, and Ag3PO4 samples. The experimental results demonstrated that TiO2 was generated as an intermediate product during the chemical reaction process between Ag3PO4 and TiOF2. Additionally, Ag nanoparticles were formed in the Ag3PO4/TiO2/TiOF2 heterojunction system. An electric field was formed between Ag3PO4 and Ag, enhancing the visible light absorption ability. Because of the Schottky potential difference, the electrons accumulate in Ag nanoparticles, thus enhancing the photocorrosion resistance of Ag3PO4. Additionally, the localized surface plasmon resonance (LSPR) effect of Ag nanoparticles greatly promoted the separation of carriers at the interface of the heterojunction. The LSPR effect leads to the co-oscillation of free electrons, which leads to the strong absorption of electromagnetic energy and enhances the photocatalytic performance of the heterojunction. The [email protected]3PO4 nanocomposites acted as electron transport media for an all-solid-state Z-scheme TFAP heterojunction system. This study provides some in-depth insights into the structural design of Z-scheme heterojunctions, which have certain implications for other catalytic systems.
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