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Anatase TiO 2 ultra-thin nanosheets (TiO 2 -NS) are synthesized by a facile hydrothermal method. Several merits are realized when employing the prepared TiO 2 -NS as lithium ion battery anode material, compared to TiO 2 nanoparticles. Firstly, the as-prepared TiO 2 -NS has high charge capacities and a specific surface area up to 98.8 m 2 g −1 , which is beneficial for the insertion of lithium ion. Secondly, the large specific surface area is helpful in enlarging the electrode/electrolyte interfacial area. Finally, the EIS result verifies short electron transfer paths. More importantly, the stability of the nanosheet structure is indirectly confirmed by the excellent cycling performance of charge capacity and the curve of charge capacities versus cycle number at different current densities. After galvanostatic charge/discharge of the batteries for 1000 cycles, the HRTEM images of post-mortem batteries directly reveal a good reversibility of the lithium ion insertion/extraction process aided by TiO 2 -NS. Thus, all these advantages and the special structure facilitate an excellent cycling performance: the charge capacity with the maximum value of 250 mAh g −1 keeps half after 2000 cycles at a current density of 840 mA g −1 (5 C). [ABSTRACT FROM AUTHOR]

In this paper, novel TiO 2 /Bi 2 WO 6 heterojunction photocatalysts with hollow microsphere structures were successfully fabricated by a one-pot glucose-assisted hydrothermal route followed by the calcination at 450 °C. The photocatalytic activities of the as-prepared photocatalysts were evaluated on the degradation of rhodamine B (RhB) aqueous solution under visible light irradiation and the results indicated that the as-prepared TiO 2 /Bi 2 WO 6 composite exhibited higher photocatalytic activity than bare TiO 2 and Bi 2 WO 6 . In addition, the TiO 2 /Bi 2 WO 6 composite with TiO 2 loading of 20 wt.% showed the highest photocatalytic activity and retained the high photocatalytic performance after four recycles for the photodegradation of RhB, confirming its stability and practical usability. The enhanced photocatalytic activity of TiO 2 /Bi 2 WO 6 composite was attributed to well matched energy band positions of TiO 2 and Bi 2 WO 6 , which facilitated the efficient separation of photogenerated electron–hole pairs and thereby led to the increasing photocatalytic activity. On the basis of calculated energy band positions, the results of photoluminescence (PL) and active species trapping experiments, the mechanism of the obviously enhanced photocatalytic performance was proposed. [ABSTRACT FROM AUTHOR]

Abstract: Arrays of TiO2 nanotubes were fabricated by the anodization of Ti foils and then used in assembling dye-sensitized solar cells (DSSCs). The role of the morphologies of the TiO2 nanotubes in the photovoltaic performances of the DSSCs was studied in terms of the surface topography and the tube length. The necessity of removing the nanoporous films from the surface of the nanotube arrays for good DSSC performance has been demonstrated. Also, it has been shown that appropriately increasing the tube length was an effective measure for enhancing both the short-circuit current density and the conversion efficiency of the DSSCs. [Copyright &y& Elsevier]

Abstract: An effective ZnO compact film (ZCF) has been introduced at the interface of fluorine doped tin oxide (FTO) substrate and mesoporous TiO2 layer, and its effect on dye-sensitized solar cells (DSSCs) has been compared to that of conventional TiO2 compact film (TCF). The ZCF and TCF prepared by spin-coating method on FTO are characterized by energy-dispersive X-ray spectroscopy (EDX), scanning electron microscopy (SEM), and UV–vis spectrophotometer. The existence of TiO2 can suppress the recombination occurring at the interface of FTO/electrolyte, resulting in a higher J sc and V oc than bare FTO. The ZCF creates an energy barrier between FTO substrate and mesoporous TiO2 layer, which not only reduces the electron back transfer from FTO to I3 − in the electrolyte, but also leads to the accumulation of photogenerated electrons, and increases the electron density in the conduction band of TiO2. The device based on FTO/ZCF substrate remarkably improves V oc and FF, finally increases energy conversion efficiency by 13.1% compared to the device based on bare FTO and 4.7% compared to the counterpart based on FTO/TCF. [Copyright &y& Elsevier]

Abstract: The photocatalytic degradation of Reactive Brilliant Blue KN-R has been investigated under UV irradiation in aqueous suspension of titanium dioxide under a variety of conditions. The degradation was studied by monitoring the change in dye concentration using UV spectroscopic technique. The effects of key operation parameters such as initial dye concentration, catalyst loading, hydrogen peroxide dosage as well as initial pH value on the decolorization extents were studied. The decolorization of the organic molecule followed a pseudo-first-order kinetics according to the Langmuir–Hinshelwood model. Under the optimum operation conditions, approximately 97.7% color removal was achieved with significant reduction in TOC (57.6%) and COD (72.2%) within 3h. Moreover, the degradation products were analyzed by GC–MS technique and probable pathways for the formation of products were proposed. [Copyright &y& Elsevier]

Abstract: The evolution of alumina coating layers on rutile TiO2 particle surfaces was investigated starting from aluminum sulfate by a chemical liquid deposition method. The morphology of the alumina coating layers was determined by transmission electron microscopy. The chemical structure and the evolution mechanism of the alumina coating layers on TiO2 surfaces were investigated by Fourier transform infrared spectroscopy, X-ray photoelectron spectroscopy, and powder X-ray diffraction techniques. The dispersibility of the alumina-coated TiO2 powders was determined by dynamic laser scattering (DLS) mode. The alumina coating layers existed in boehmite phase, AlOOH, and anchored at the surfaces of TiO2 via Ti–O–Al bond. The formation of alumina coating layers on TiO2 surfaces depended on the pH value of the deposition solution and the alumina loading. After coated by alumina layer, the dispersibility, whiteness, brightness, and light scattering index of the resultant samples were promoted. [Copyright &y& Elsevier]

Abstract: Hexatitanate (K2Ti6O13) and titanium dioxide (TiO2) fibers were synthesized by ion-exchange method using fibrous potassium titanate (K4Ti3O8) as initial material. Fibrous K4Ti3O8 was prepared by treating TiO2 with 80wt.% concentrated KOH solution at 220°C for 2h under atmospheric pressure. Then, high qualities of K2Ti6O13 and TiO2 fibers were formed by a thermal treatment of the hydrolytic intermediates K4−b H b Ti3O8 (1.2≤ b ≤3.0) and H4Ti3O8, which were quantitatively obtained by controlling the pH value ranging from 10.9 to 12.0 and from 2.0 to 5.0 in the hydrolytic process of K4Ti3O8, respectively. Based on the experimental results, the possible ion-exchange and phase transformation mechanisms in the reaction process were discussed. [Copyright &y& Elsevier]

We demonstrate a method for incorporating plasmon metallic nanoparticles in hierarchical rutile TiO 2 clusters (RTC) assembled from single-crystal nanospindles. The RTC could efficiently improve the diffusion of the photoelectrons, which can be ascribed to the improvement of the connectivity by bridging the neighbouring microflowers through the single-crystal nanospindles. But not all the nanospindles are tightly interconnected, hence organic colloid has been prepared for post-treatment of the device based on RTC by the generation of TiO 2 nanoparticles. When added into Au nanoparticles, localized electric fields can be produced, because Au can excite dye molecules more intensively than incident far-field light. The surface plasmon synergistic effect had been investigated by Uv-vis absorption spectrum of Au@ organic colloid and the relative change of the IPCE. As a result, the cell based on RTC exhibits an overall conversion efficiency of 7.68%, indicating a 17% promotion compared with that derived from commercial P25 (6.58%) which could be ascribed to faster electron transfer of single-crystal nanospindles. With the Au nanoparticles incorporation in RTC, the device achieves a conversion efficiency of 9.15%, resulting in a 11% increase compared to the RTC device post-treated by organic colloid without Au nanoparticles (8.24%), which is attributed to the surface plasmon synergistic of Au nanoparticles. [ABSTRACT FROM AUTHOR]

Abstract: Light harvesting in dye-sensitized solar cells (DSSCs) mediated by plasmonic metallic nanoparticles and sub-micron light-scattering metal oxides is a facile and cost-effective approach to achieving high device performance. Ag nanoparticles, protected by thin shells of TiO2, were incorporated in TiO2 photoanode. The large plasmonic near-field intensity generated by these nanoparticles caused an 18.3% rise in photocurrent, which resulted in an enhanced efficiency of 6.23% as compared to 5.29% efficiency of DSSC based on unmodified TiO2 photoanode. In addition, DSSC with TiO2 nanofibers (NFs) embedded in TiO2 photoanode was also constructed, which because of the efficient light scattering ability of the nanofibers, attained an efficiency of 7.14% as a result of a current rise of 36.9%. Another DSSC was assembled with Ag NPs added to the photoanode of the NFs-based DSSC to further boost cell performance. The addition of Ag NPs, however, did not produce an appreciable change in the cell performance. The reason for this unexpected outcome was probably due to the low internal resistance associated with charge recombination and large resistance to electron transport in the cell as determined by electrochemical impedance analysis computed in this work. [Copyright &y& Elsevier]

Abstract: TiO2 doping has been widely used to improve the performance of dye-sensitized solar cells. In this paper, we study the use of N as a dopant of TiO2 in dye-sensitized solar cells (DSSCs), analyzing the effect on the photovoltaic properties of the cells based on different amounts of N doping. Results indicate that the dye absorption is increased, which would enhance the amount of photoelectron; moreover, the resistance (R 3) of the electron transport within photoelectrode and electron lifetime of it are improved by N doping. The above two reasons would lead the high short circuit current density (J sc). However, owing to the sites of recombination and severe defects introduced, the trend of dye absorption, R 3 and electron lifetime is opposite when the amount of N doping is more than 3%. Finally, we find that the optimal amount of N doing is 3%, which outstandingly increase the performance of DSSCs. The conversion efficiency of the DSSCs can be reached to 6.25% when using the 3% N-doped TiO2 photoelectrode, and this efficiency is 23.03% higher than that of the pure TiO2. [Copyright &y& Elsevier]

Abstract: The catalytic activities of kieselguhr-, TiO2-, and Al2O3-supported Ni catalysts in hydrogenation of p-nitrophenol to p-aminophenol were investigated. The supported Ni catalysts were characterized by N2 adsorption/desorption, X-ray diffraction, temperature-programmed reduction, and temperature-programmed desorption of ammonia techniques. The catalytic activities of the supported Ni catalysts were in an order of Ni/kieselguhr ≫ Ni/TiO2 > Ni/Al2O3. The acidities of the supported Ni catalysts were in an order of Ni/Al2O3 ≫ Ni/TiO2 > Ni/kieselguhr. The acidity of the supported Ni catalyst significantly affected the catalytic activity. [Copyright &y& Elsevier]

Controllable three-dimensional villose titanium dioxide architectures grown on carbon textiles are fabricated by a facile one-step in-situ hydrothermal method at low temperatures. It has in fact been proven to be an effective method to reduce self-aggregation and promote lithium-ion intercalate/extract via building 3D architectures based on 2D conductive materials. More importantly, the freestanding electrodes without any addition of conductive agents and polymeric binders reveal significant improvement in high-rate capacity and cycling performance. [ABSTRACT FROM AUTHOR]

We demonstrate a facile approach to synthesize shape-controlled anatase titania with tailored facets via the employment of 3-aminopropyltrimethoxysilane (APTMS) as shape-tunable and capping agent. The as-synthesized anatase TiO 2 nanorods was highly crystalline and exposed with {001} and {100} facets. The LIBs based on these highly crystalline TiO 2 nanorods with tailored facets reveals significant improvement in high-rate capacity and cycling performance. More importantly, this methodology enable the industrial application of anatase titania as anode materials for LIBs without high temperature annealing process. [ABSTRACT FROM AUTHOR]

Abstract: Trace amount chromium-doped (Cr-doped) TiO2 is prepared by hydrothermal method for dye-sensitized solar cells (DSSCs). The effect on photovoltaic performance of the cells is investigated via control of the concentrations of Cr doped in TiO2. Rutile phase increases when Cr is incorporated into TiO2 while the property of electron transport in photoelectrodes is improved by doping Cr which results in a reduced resistance (R ct) of the electron transport within mesoporous layer and an improved electron lifetime. The regularity of R ct and electron lifetime is reversed when the level of doped Cr exceeds 50 ppm. On the other hand, owing to the doping effect of Cr, the short-circuit photocurrent density (J sc) of DSSCs is remarkably enhanced and reaches maximum. Consequently, the overall energy conversion efficiency enhances to 6.35% with Cr-doped TiO2 of 50 ppm, which is 14.62% higher than that with undoped TiO2. In general, compared with undoped TiO2, Cr-doped TiO2 is a better photoanode material and a more promising alternative for high efficient DSSCs. [Copyright &y& Elsevier]

Abstract: Binary Al2O3/SiO2-coated rutile TiO2 composites were prepared by a liquid-phase deposition method starting from Na2SiO3·9H2O and NaAlO2. The chemical structure and morphology of binary Al2O3/SiO2 coating layers were investigated by Fourier transform infrared spectroscopy, X-ray photoelectron spectroscopy, TG–DSC, Zeta potential, powder X-ray diffraction, and transmission electron microscopy techniques. Binary Al2O3/SiO2 coating layers both in amorphous phase were formed at TiO2 surfaces. The silica coating layers were anchored at TiO2 surfaces via Si–O–Ti bonds and the alumina coating layers were probably anchored at the SiO2-coated TiO2 surfaces via Al–O–Si bonds. The formation of continuous and dense binary Al2O3/SiO2 coating layers depended on the pH value of reaction solution and the alumina loading. The binary Al2O3/SiO2-coated TiO2 composites had a high dispersibility in water. The whiteness and brightness of the binary Al2O3/SiO2-coated TiO2 composites were higher than those of the naked rutile TiO2 and the SiO2-coated TiO2 samples. The relative light scattering index was found to depend on the composition of coating layers. [ABSTRACT FROM AUTHOR]

Abstract: TiO2-coated sericite powders were prepared by the chemical deposition method starting from lamellar sericite and TiCl4 in the presence or absence of La3+ cations. After calcination at 900°C for 1h, the resultant TiO2 nanoparticles on the sericite surfaces existed in anatase phase. The light scattering indexes of the TiO2-coated lamellar sericite powders were dozens of times higher than that of the naked lamellar sericite powders. The presence of La3+ in the deposition solution was beneficial to the formation of the small-sized anatase TiO2 nanoparticles, resulting in the formation of the dense and uniform island-like TiO2 coating layers in a large range of the weight ratios of TiO2 to sericite from 5% to 20%. The TiO2-coated lamellar sericite powders prepared in the presence of La3+ had higher light scattering index than that prepared in the absence of La3+. XPS analysis shows that when La3+ cations were absent in the reaction solution, TiO2 coating layers anchored at the sericite surface via the Ti–O–Si and Ti–O–Al bonds. The presence of La3+ cations caused the formation of Si–O–La and Al–O–La bonds at the sericite surface and Ti–O–La bond at the surface of TiO2 coating layers. After coating TiO2 on the sericite surface, the yellowness of the TiO2-coated sericite powders obviously increased and the brightness slightly decreased. [Copyright &y& Elsevier]