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Titanium Dioxide (Anatase and Rutile): Surface Chemistry, Liquid–Solid Interface Chemistry, and Scientific Synthesis of Supported Catalysts ... Elucidation of polyethylene glycol adsorption at the solid–H 2 O(l) interfaces of anatase TiO 2 (101) using density functional theory and molecular dynamics simulations. Journal of Materials ...
The rutile form of titanium dioxide (r-TiO 2) usually shows a photocatalytic activity lower than that of anatase-TiO 2 (a-TiO 2).Nevertheless, there are numerous examples of sometimes unexpectedly high activity of r-TiO 2.This material may appear to be particularly useful when a noncomplete and selective photocatalytic oxidation of organic substrates …
The light-induced phase transition of TiO 2 nanoparticles from anatase to rutile structure is reported depending on the surrounding environment, the transition being accomplished under oxygen-poor conditions. The …
Titanium dioxide, TiO 2, is an important photocatalytic material that exists as two main polymorphs, anatase and rutile. The presence of either or both of these …
We demonstrate, through a combination of state-of-the-art materials simulation techniques and X-ray photoemission experiments, that a type-II, staggered, band alignment of ~ 0.4 eV exists between...
The material contains both rutile and anatase phases of TiO 2 according to XRD analysis (Fig. 2c). The one strobili and two mille-feuilles structures shown in surface view SEM (Fig. 2a ) were ...
Experimental studies of the surface reactions of photocatalyzed or photoelectrocatalyzed water oxidation on rutile, anatase, and brookite TiO2 show significant differences between the three polymorphs. Yet a fundamental understanding of the differences is still lacking. In this work, we carried out a systematic comparative …
Heterophase Polymorph of TiO 2 (Anatase, Rutile, Brookite, TiO 2 (B)) for Efficient Photocatalyst: Fabrication and Activity. by. Diana Rakhmawaty Eddy. 1,*, Muhamad Diki Permana. 1,2,3, Lintang Kumoro Sakti. 1, …
Abstract. TiO 2 has many polymorphs, among which rutile is the most thermodynamically stable. Bulk anatase TiO 2 is usually a metastable phase at room …
Rutile is deep red while anatase is yellow to blue. Rutile has a high absorbance property than anatase. Rutile and anatase are both used in the white pigmentation of paints, paper, and ceramics. Sunscreens contain rutile because of its absorbance of ultraviolet rays. Issues have risen regarding titanium dioxide as being carcinogenic. Rutile and ...
Anatase, rutile, and TiO 2 (B) have all been examined for their potential application in Li- and Na-based battery materials, and a wide range of results has been reported. It has been experimentally confirmed that anatase can readily incorporate Li. For Na, however, the situation is not as clear and is dependent on the TiO 2 nanostructure. Xiong et al. tested …
The cell parameters of anatase were obtained to be a/b = 3.7794 Å and c = 9.4984 Å, and for rutile a/b = 4.5847 Å and c = 2.9557 Å (from refinement in Figure S1 in SI). The anatase showed a ...
Anatase and brookite (both TiO 2) are polymorphs of rutile as are akaogiite and riesite.Anatase has a tetragonal structure (space group I4 1 /amd) whilst brookite is orthorhombic (space group Pbca).Akaogiite is monoclinic (space group P2 1 /c), riesite is also monoclinic with space group P2/c (El Goresy et al., 2010; Tschauner et al., …
High-temperature X-ray diffractograms show the polymorphic types of TiO 2 that are available at various temperatures. The phase transformation from anatase (DB card number 00-021-1272) to rutile (DB card number 01-073-1232) began around 400 °C and was completed at 800 °C (Fig. 1, Fig. 2).The precise phase transition temperature of …
The bandgap of rutile and anatase TiO 2 is of 3.0 and 3.2 eV respectively. Counting of all the possible alignments of their relative position of the conduction band (CB) ...
Biphasic TiO 2 with adjustable crystalline phases was prepared by the hydrothermal-calcination method assisted by nitric acid (HNO 3) and hydrogen peroxide (H 2 O 2), using potassium titanate oxalate (K 2 TiO(C 2 O 4) 2) as the titanium source.The influences of H 2 O 2 volume on anatase and rutile contents and photocatalytic activity of biphasic TiO 2 …
a, Ball-and-stick model of anatase TiO 2 (101). Inset: details of the structure. O atoms are red, Ti atoms are grey. This notation is used in all of the figures. b, STM image ( Vsample =+1.5 V ...
Therefore, the corresponding final products are nominated as anatase TiO 2 (TO-A), anatase/rutile TiO 2 (TO-AR) and rutile TiO 2 (TO-R). 2.2. Morphological and structural characterization. Thermal stability was measured on a Netzsch Thermo Microbalance TG 209 F1 Libra heated to 900 °C under a nitrogen atmosphere at a …
The physicochemical properties of titanium dioxide (TiO 2) depend strongly on the crystal structurepared to anatase, rutile TiO 2 has a smaller bandgap, a higher dielectric constant, and a higher refractive index, which are desired properties for TiO 2 thin films in many photonic applications. Unfortunately, the fabrication of rutile thin films …
The anatase TiO 2 (001) surface has attracted extensive attention in surface science and for practical applications because of its excellent performance. However, the highly reactive (001) surface usually reconstructs to a (1 × 4)-(001) surface, which may potentially alter its properties. ... anatase, rutile, brookite, and TiO 2 (B). Among ...
TiO 2 is a promising photoanode material for photoelectrochemical (PEC) water splitting, but its severe bulk recombination of photogenerated carriers, sluggish oxygen evolution reaction (OER) kinetics and poor visible light response are the main bottleneck problems. Here, the carbon quantum dots (CQDs) modified anatase/rutile …
Anatase/rutile mixed-phase TiO 2 nanoparticles were synthesized through a simple sol-gel route with further calcination using inexpensive titanium tetrachloride as a titanium source, which effectively reduces the production cost. The structural and optical properties of the prepared materials were characterized by X-ray diffraction (XRD), …
Figure 1 illustrates the most important experimental results concerning the first nanomaterial system—undoped n-type TiO 2.XRD (Fig. 1a) for as-prepared TiO 2 nanopowder indicates the predominance of anatase polymorphic form. The content of rutile is low as determined from the analysis of this XRD pattern and amounts to f R = 0.07. As …
[ 23] In the present study, we aim to provide a comprehensive understanding of initial crystal structures during the reduction process of TiO 2. For this purpose, two …
The 2D lateral anatase–rutile TiO 2 phase junctions with controllable oxygen vacancies were fabricated through the melted Al reduction. The 2D TiO 2 NSs and Al powders were separately positioned in a two-zone tube furnace (Fig. S1) and then evacuated to a base pressure of 0.5 Pa.
Abstract. The light-induced phase transition of TiO 2 nanoparticles from anatase to rutile structure is reported depending on the surrounding environment, the transition being accomplished under oxygen-poor …
The phase transition from rutile to anatase by carbon ion-implantation in TiO 2 structure improves the efficiency of dye-sensitized solar cells (5.32%) [32], which increases the light-harvesting ...
Experimentally, anatase has a slightly larger band gap sE1d than rutile, 3.2 (Ref. 22) versus 3.0 eV (Ref. 23).The difference is somewhat overestimated in the calculations: E1=2.61 and 2.14 eV for anatase and rutile, respectively, at KLS (2.19 and 1.81 eV, respectively, in G), see Table I. The band gaps are underestimated, as usual in DFT.
A comparison of PL spectra of anatase (A and A2) and rutile (R) samples in Fig. 7 reveals a difference between the high-energy bands of anatase and rutile due to differences in the band structure of the two TiO 2 polymorphs [59], [61]. On the other side, the positions of shallow level traps at 2.8, 2.7, 2.55 and 2.34 eV remained the same.
The anatase and rutile planes of TiO 2 nanoparticles made with 0.6 M of Ti precursors exhibit the same XRD peak intensity. This can be attributed to TiO 2 crystal phase transformation from rutile to anatase with increase in titanium precursor. Anatase is more stable at low temperature and transfers to rutile phase at high temperature.
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