Search

Nanocrystalline TiO2 nanotube electrodes were fabricated by electrochemically anodizing the titanium in the electrolyte with an ethylene glycol with addition of 0.5% by weight NH4F and amount of water (2% w/w). Structural properties of the obtained coatings have been investigated by scanning electron microscopy and Raman and XRD spectroscopy. When illuminated by a sunlight simulator, these electrodes demonstrate high activity in photoelectrochemical degradation of anions of phenylacetic acid from aqueous solutions of 0.1 M Na2SO4. Results of intensity-modulated photocurrent spectroscopy show that the photoelectrocatalysis efficiency is explained by suppression of the electron–hole pair recombination and increase in the rate of photo-induced charge transfer. Thus, nanotubes from TiO2 can be considered as effective photoanodes. [ABSTRACT FROM AUTHOR]

In order to investigate the effect of organic electrolytes on the photocurrent performance of TiO 2 nanotubes, four kinds of fluoride containing electrolyte were prepared. This work focuses on the effect of electrolyte on the photocurrent response of TiO 2 nanotubes. The results show that the electrolyte is an important influence on the photocurrent response. Appropriate proportion of polyethylene glycol (PEG) organic solvent can improve the performance of photocurrent response. The addition of excessive organic solvent will make TiO 2 nanotubes lose the ability of photocurrent response. Suitable surface porosity is a necessary condition for the sample to have photocurrent response. Too low porosity hinders the photoelectric property. The reason for the better photoelectric properties of the sample prepared in 50 wt% PEG electrolyte is explained by the ionic current and electronic current theory. The results show that a more stable ratio of accumulated charge by ionic and electronic currents per unit area creates a more stable photocurrent response when the voltage is increased from 40 V to 60 V. [ABSTRACT FROM AUTHOR]

Microcantilevers (MCs) are highly sensitive sensors capable of detecting mass changes on the surface at the nanogram and even picogram scale. In this study, microcantilevers were fabricated for the first time using the Sodick AP250L Wire electrical discharge machining (EDM) from amorphous 2826MB (Fe40Ni38Mo4B18) ferromagnetic ribbons. This method is advantageous because it allows for the simultaneous production of a large number of microcantilevers, with about 100 MCs being produced in a single manufacturing process. Additionally, a straightforward and cost-effective measurement system was developed to measure the resonance frequency and frequency shift of the MC entirely through magnetic means, a technique not previously reported in the literature. To evaluate the performance of the MC, we employed it as a humidity sensor. For the TiO2-NT-coated MC, a frequency shift of approximately 202 Hz was observed when the humidity level changed from 5% to 95% relative humidity (RH). [ABSTRACT FROM AUTHOR]

Titanium dioxide nanotubes (TiO2 NTs) have been widely investigated in the past 20 years due to a variety of possible applications of this material. Indeed, their high surface area and tunable morphology can easily implement key features of TiO2, such as its biocompatibility and photo‐ and electrocatalytic properties. This combination makes TiO2 NTs perfect candidates for multifunctional applications ranging from biomedical application to sensing and energy devices. Herein, we present TiO2 NTs grown by anodic oxidation on top of a titanium foil in an ethylene glycol‐based electrolyte with NH4F. The as‐grown amorphous nanotubes were then subjected to annealing in a reducing atmosphere at different temperatures while maintaining their amorphicity. The morphological, physicochemical, and electronic properties were then thoroughly evaluated to assess their use in different fields, from energy storage devices to photo‐catalytical applications. [ABSTRACT FROM AUTHOR]

This study presents a comparative analysis of anodization and hydrothermal techniques for synthesizing TiO2 nanotubes directly on titanium foil. It emphasizes its advantages as a substrate due to its superior conductivity and efficient charge transfer. Optimized synthesis conditions enable a thorough evaluation of the resulting nanotubes' morphology, structure, and optical properties, ultimately assessing their photoelectrochemical and photocatalytic performances. Scanning electron microscopy (SEM) reveals differences in tube diameter and organization. An X-ray diffraction (XRD) analysis shows a dominant anatase (101) crystal phase in both methods, with the hydrothermally synthesized nanotubes exhibiting a biphase structure after annealing at 500 °C. UV–Vis and photoluminescence analyses indicate slight variations in band gaps (around 0.02 eV) and recombination rates. The anodized TiO2 nanotubes, exhibiting superior hydrophilicity and order, demonstrate significantly enhanced photocatalytic degradation of a model pollutant, amido black (80 vs. 78%), and achieve a 0.1% higher photoconversion efficiency compared to the hydrothermally synthesized tubes. This study underscores the potential advantages of the anodization method for photocatalytic applications, particularly by demonstrating the efficacy of direct TiO2 nanotube growth on titanium foil for efficient photocatalysis. [ABSTRACT FROM AUTHOR]

New technologies of microelectronics are emerging to reduce the size of devices and combine them into more compact ultralow power systems. Betavoltaic power sources (BVPSs) can serve as power generators of such order. BVPSs consist of a combination of betavoltaic cells (BVCs) based on long-lived radioisotopes of beta radiation and semiconductor converters (SCs). One of the key tasks for increasing the power of BVCs is the selection of SCs that can efficiently convert the energy of beta particles into electricity. Currently, semiconductor structures with a developed surface and a high band gap are considered to be perspective SCs. In present work, arrays of titanium dioxide nanopores (TiO2 NPs) synthesized by common electrochemical anodization were chosen as a SCs. These SCs were part of BVCs based on nickel-63 with an activity of ~10 Ci/g. TiO2 NPs with an amorphous structure in the composition of BVC demonstrated low electrical parameters. To increase them, we modified TiO2 NPs by the hydrothermal method in a solution of Sr(OH)2 with a concentration of 0.05 mol/L at various times. These experiments were carried out in order to convert TiO2 (anatase) into structure-like SrTiO3. We found that the electrical parameters of the SCs increased with the duration of the modification time. The best result was obtained in the case of modification for 3 h—the BVC generated a short circuit current of 2.9 nA and open circuit voltage of 0.8 V and had a maximum power of 0.8 nW at 0.45—0.5 V. The obtained electrical parameters in combination with the miniature dimensions of the BVCs open up the potential possibility of creating a BVPS with an increased power density. [ABSTRACT FROM AUTHOR]

Zirconia has become a popular choice for indirect restorations; however, adhesion to this material remains a challenge. The present study aimed to evaluate surface characteristics and bond strength to tetragonal Y-TZP and cubic Y-PSZ zirconia submitted to experimental surface treatments. Specimens of Y-TZP (T) and Y-PSZ (P) were prepared and divided into groups: Tf-A) thin TiO2 film functionalized with 3-(aminopropyl)trimethoxysilane (APTMS); Tf) thin TiO2 film; MNt-A) manual application of TiO2 nanotubes with APTMS; MNt) manual application of TiO2 nanotubes; VNt-A) vacuum application of TiO2 nanotubes with APTMS; VNt) vacuum application of TiO2 nanotubes; C) control with Al2O3 sandblasting. Characterization with x-ray photoelectron spectroscopy (XPS) and scanning electron microscopy (SEM) was done. Bond strength was evaluated by microshear bond strength (µSBS). Data were analyzed by two-way ANOVA and Tukey’s HSD tests (α = 0.05). XPS showed signals for elements O 1 s, Ti 2p, and Zr 3d 5/2. In addition, high-resolution demonstrated Ti-O-Si and Zr-O-Si bonding for treatments with TiO2 and APTMS for T-Tf-A/P-Tf-A. SEM presented a homogeneous film for T-Tf/T-Tf-A/P-Tf/P-Tf-A and cluster formations for all nanotube groups. Control groups for both Y-TZP and Y-PSZ showed clear surfaces. No differences of µSBS were seen between experimental surface treatments and the controls, except for T-MNt-A/T-VNt-A/P-MNt-A/P-VNt-A, which showed the lowest mean µSBS and highest incidence of pre-test failures. Surface treatments with TiO2 nanostructures were effective in modifying the surface of both zirconia materials evaluated, providing strong covalent bonds, changes to the surface topology, and shear bond strength comparable to conventional sandblasting protocols.

Porous anodic oxides have become a research hotspot, but their formation mechanisms are still controversial. The classical field-assisted dissolution theory (FADT) is a theory of top-down dissolution to form nanotubes. However, certain key problems such as the three-stage current-time curve in anodizing process cannot be explained by this theory. The oxygen bubble mold (OBM) is a new mechanism of bottom-up growth of nanotubes, which can explain the phenomenon that cannot be explained by the FADT. Compared to the anodic TiO 2 nanotubes, ZrO 2 nanotubes have a more complex anodizing current-time curve which is not studied sufficiently. Under certain conditions, there are double complete three-stage current-time curves and two-layer nanotubes. In this study, to explore the formation mechanism of anodic ZrO 2 nanotubes, the current-time curve and the interesting morphology were analyzed, after zirconium anodizing and SEM characterizing. An interesting three-layer structure composed of upper nanotubes, dense layer and lower nanotubes formed by zirconium anodizing is reported for the first time. The lower nanotubes and the dense layer are tightly bonding, which strongly refutes the FADT. The OBM was used to explain this phenomenon, which promoted the development of the formation mechanism of anodic ZrO 2 nanotubes. [ABSTRACT FROM AUTHOR]

The potential of photocatalysis applications rapidly expands, offering energy-efficient solutions across various industries. Titanium dioxide nanotubes (TiO2 NTs/TNTs) are emerging as effective catalysts for water filtration techniques. Electrochemical anodization is the preferred method for producing suitable TNTs on a titanium plate. The key challenge lies in fabricating these desired TNTs efficiently in terms of time, cost, and energy. These effective nanotubes can achieve optimal photocatalytic dye degradation by modifying their optical and morphological properties. This paper explores the fabrication of NTs by manipulating different parameters and the successful application of Titania in dye degradation through appropriate doping. [ABSTRACT FROM AUTHOR]

Titanium dioxide (TiO2) nanotubes were obtained by the anodization process, applying a potential of 30 V for 2 h in an electrolyte composed of NH4F, H2O and ethylene glycol. The nitrogen doping of the obtained nanostructures was studied and the influence of the use of different temperatures during the thermal treatments 400, 500 and 600°C, on the formed nanotubes were evaluated. The morphology and crystalline structure of the obtained materials were determined by field emission gun scanning electron microscopy and X-ray diffraction. The optical properties were evaluated by UV–Vis diffuse reflectance spectroscopy and the photoelectrochemical properties by linear sweep voltammetry curves. The photocatalytic activity of nanotubes was evaluated by degradation of glycerol in aqueous medium using UV and visible radiation. TiO2 nanotubes developed photoactivity, photoelectrochemical behaviour and presented catalytic activity for glycerol degradation, which is more evident with UV radiation. The sample thermally treated at 500°C was the one that presented superior photoelectrochemical behaviour and superior photocatalytic activity when exposed to both UV and visible radiation. [ABSTRACT FROM AUTHOR]

Copyright of Dental Press Endodontics is the property of Dental Press International and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Herein, the growth of transparent TiO2 nanotube (NT) layers is investigated by complete self‐organized anodization of a metallic Ti layer on fluorine‐doped tin oxide glass, deposited by electron beam evaporation. An initiation‐free open‐top tube morphology can be obtained for such transparent TiO2 NTs using an optimized second anodization approach combined with a post‐ultrasonication process. The photoelectrochemical properties of open‐top tubes exhibit notable enhancement, primarily attributed to their rapid electron‐transfer kinetics, with a ≈33% increase in the incident‐photon‐to‐electron conversion efficiency value (at 350 nm wavelength) in comparison to classical (initiation‐covered) NTs with a comparable morphology. [ABSTRACT FROM AUTHOR]

Titanium dioxide synthesis and modification by chemical, electrochemical, and mechanochemical methods are briefly outlined. The atomistic structure, nanostructure, morphology, optical characteristics, functional properties, and peculiar features of the semiconductor material are described. Practical applications of titanium dioxide in catalysis, sorption, and biomedicine are described. [ABSTRACT FROM AUTHOR]

This article studies the role of electrochemical parameters in controlling the morphology of oxidized TiO2 nanotubes and the electrochemical performance of modified TiO2 nanotubes. Humidity is a key factor for fabricating TiO2 nanotubes. When the relative humidity belows 70%, the TiO2 nanotubes can be successfully prepared. What's more, by changing the anodization voltage and time, the diameter and the length of TiO2 nanotubes can be adjusted. In addition, the TiO2 nanotubes are modified through electrochemical self-doping and loading Pt metal particles on the surface of the nanotubes, which promotes the performance of the supercapacitor. The sample anodized at 100 V for 3 h has a specific capacity of up to 2.576 mF/cm² at a scan rate of 100 mV/s after self-doping, and its capacity retention rate still remains at 89.55% after 5 000 cycles, demonstrating excellent cycling stability. The Pt-modified sample has a specific capacity of up to 3.486 mF/cm² at the same scan rate, exhibiting more outstanding electrochemical performance. [ABSTRACT FROM AUTHOR]

Inspired by the strong light absorption of carbon nanotubes, we propose a fabrication approach involving one-dimensional TiO 2 /Bi 2 S 3 QDs nanotubes (TBNTs) with visible red-light excitable photoelectric properties. By integrating the construction of heterojunctions, quantum confinement effects, and morphological modifications, the photocurrent reached 9.22 µA/cm2 which is 66 times greater than that of TiO 2 nanotubes (TNTs). Then, a red light-responsive photoelectroactive hydrogel dressing (TBCHA) was developed by embedding TBNTs into a collagen/hyaluronic acid-based biomimetic extracellular matrix hydrogel with good biocompatibility, aiming to promote wound healing and skin function restoration. This approach is primarily grounded in the recognized significance of electrical stimulation in modulating nerve function and immune responses. Severe burns are often accompanied by extensive damage to epithelial-neural networks, leading to a loss of excitatory function and difficulty in spontaneous healing, while conventional dressings inadequately address the critical need for nerve reinnervation. Furthermore, we highlight the remarkable ability of the TBCHA photoelectric hydrogel to promote the reinnervation of nerve endings, facilitate the repair of skin substructures, and modulate immune responses in a deep burn model. This hydrogel not only underpins wound closure and collagen synthesis but also advances vascular reformation, immune modulation, and neural restoration. This photoelectric-based therapy offers a robust solution for the comprehensive repair of deep burns and functional tissue regeneration. We explore the fabrication of 1D TiO 2 /Bi 2 S 3 nanotubes with visible red-light excitability and high photoelectric conversion properties. By integrating heterojunctions, quantum absorption effects, and morphological modifications, the photocurrent of TiO 2 /Bi 2 S 3 nanotubes could reach 9.22 µA/cm², which is 66 times greater than that of TiO 2 nanotubes under 625 nm illumination. The efficient red-light excitability solves the problem of poor biosafety and low tissue penetration caused by shortwave excitation. Furthermore, we highlight the remarkable ability of the TiO 2 /Bi 2 S 3 nanotubes integrated photoelectric hydrogel in promoting the reinnervation of nerve endings and modulating immune responses. This work proposes an emerging therapeutic strategy of remote, passive electrical stimulation, offering a robust boost for repairing deep burn wounds. [Display omitted] [ABSTRACT FROM AUTHOR]

This paper reports on the coating of heterostructured TiO2 nanopores/nanotubes on Ti substrates by anodizing at high voltages to design surfaces for biomedical implants. As the anodized voltage from 50 V to 350 V was applied, the microstructure of the coating shifted from regular TiO2 nanotubes to heterostructured TiO2 nanopores/nanotubes. In addition, the dimension of the heterostructured TiO2 nanopores/nanotubes was a function of voltage. The electrochemical characteristics of TiO2 nanotubes and heterostructured TiO2 nanopores/nanotubes were evaluated in simulated body fluid (SBF) solution. The creation of heterostructured TiO2 nanopores/nanotubes on Ti substrates resulted in a significant increase in BHK cell attachment compared to that of the Ti substrates and the TiO2 nanotubes. [ABSTRACT FROM AUTHOR]

This study focuses on the surface structures and microstructural changes of titanium dioxide nanotubes, when electrochemically coated with platinum and/or palladium. Ti samples anodized in a fluorine-containing electrolyte exhibit self-organized nanotubes of varying diameters with open pores. Annealing at 773 K led to compaction of the porous layer, the formation of cracks, and the appearance of corrugation in the nanotubes. The deposition of platinum produced a transition from a nanotubular surface structure to a microcrystalline structure consisting of rutile crystallites. The palladium-coated samples showed fused blocks characteristic of titanium suboxides. The tubular structure was preserved, even after crystallization. SEM images revealed a comb-like pattern in coatings with varying metal content. XRPD analysis confirmed the presence of anatase and elemental titanium. PdO was detected on the surface of the thermally treated samples. For samples co-treated with Pd and Pt, mutual diffusion of the two metals took place during the heat treatment. The findings reveal surface characteristics, metal deposition effects, and phase composition of titania nanotubes, providing valuable insights for further research. [ABSTRACT FROM AUTHOR]

TiO2 nanotube arrays (TNTA) were prepared by anodization, and then bismuth oxide (Bi2O3) was deposited on TNTA by vacuum impregnation‐chemical precipitation method to prepare Bi2O3@TNTA composite electrodes, which were used to detect 4‐nitrophenol (4‐NP) as an electrochemical (EC) sensor. The effects of the Bi2O3 loading amount and the pH value of the detection solution on the detection performance were exhaustively studied. Under best conditions, the linear range is 5 μΜ–30 mM, the sensitivity is 0.6696 μA ⋅ μM−1 ⋅ cm−2, and the limit of detection is 0.64 μΜ. The composite electrodes are characterized by outstanding reproducibility, superior stability and strong selectivity. [ABSTRACT FROM AUTHOR]

Nanotechnology is constantly advancing in dental science, progressing several features aimed at improving dental implants. An alternative for surface treatment of dental implants is electrochemical anodization, which may generate a nanotubular surface (TiO 2 nanotubes) with antibacterial potential and osteoinductive features. This systematic review and meta-analysis aims to elucidate the possible antibacterial properties of the surface in question compared to the untreated titanium surface. For that purpose, was performed a systematic search on the bases PubMed, Lilacs, Embase, Web Of Science, Cinahl, and Cochrane Central, as well as, manual searches and gray literature. The searches resulted in 742 articles, of which 156 followed for full-text reading. Then, 37 were included in the systematic review and 8 were included in meta-analysis. Fifteen studies revealed significant antibacterial protection using TiO 2 nanotube surfaces, while 15 studies found no statistical difference between control and nanotextured surfaces. Meta-analysis of in vitro studies demonstrated relevant bacterial reduction only for studies investigating Staphylococcus aureus in a period of 6 h. Meta-analysis of in vivo studies revealed three times lower bacterial adhesion and proliferation on TiO 2 nanotube surfaces. TiO 2 nanotube topography as a surface for dental implants in preclinical research has demonstrated a positive relationship with antibacterial properties, nevertheless, factors such as anodization protocols, bacteria strains, and mono-culture methods should be taken into consideration, consequently, further studies are necessary to promote clinical translatability. [Display omitted] • TiO 2 nanotubes as an implant surface topography was systematically revised according to their antibacterial potential. • Nanotubular surfaces revealed to induce antibacterial responses. • Preclinical research showed favorable antibacterial outcomes for TiO 2 nanotubes compared to untreated Ti. • Further research is needed to design complex studies evaluating TiO 2 nanotube surfaces in clinical set. [ABSTRACT FROM AUTHOR]

Design of experiments is a powerful planning technique that optimizes processes and reduces experimental variability. This research aims to optimize the hydrothermal synthesis of TiO2 nanotubes with a high specific surface area (SSA). A 22 factorial design was applied to investigate the influence of temperature and time on nanotube formation, achieving SSA above 350 m2 g−1. A Doehlert design combining SSA with morphology reveals closely related responses and a defined maximum surface. Microscopy shows that nanotube formation is favored at lower temperatures and longer treatment times, with the optimal condition at 120 °C for 36 h. Higher temperatures yield cauliflower-like nanostructures and provide insight into how synthesis conditions affect the morphology and nanoparticle properties. XRD and Raman spectroscopy analysis revealed that, although the anatase phase played a vital role in nanotube formation, the materials exhibited a combination of crystalline phases, including the discovery of an unidentified phase. [ABSTRACT FROM AUTHOR]

Titanium dioxide (TiO2) is the material of choice for photocatalytic and electrochemical applications owing to its outstanding physicochemical properties. However, its wide bandgap and relatively low conductivity limit its practical application. Modifying TiO2 with carbon species is a promising route to overcome these intrinsic complexities. In this work, we propose a facile method to modify TiO2 nanotubes (NTs) based on the remnant organic electrolyte retained inside the nanotubes after the anodization process, that is, without removing it by immersion in ethanol. Carbon‐modified TiO2 NTs (C‐TiO2 NTs) showed enhanced H2 evolution in photocatalysis under UV illumination in aqueous solutions. When the C‐TiO2 NTs were subjected to UV light illumination, the carbon underwent modification, resulting in higher measured photocurrents in the tube layers. After UV illumination, the IPCE of the C‐TiO2 NTs was 4.4‐fold higher than that of the carbon‐free TiO2 NTs. [ABSTRACT FROM AUTHOR]

This study aimed to investigate the fabrication and characterization of hexagonal titanium dioxide nanotubes (hTNTs) compared to compact TiO2 layers, focusing on their structural, electrochemical, corrosion, and mechanical properties. The fabrication process involved the sonoelectrochemical anodization of titanium foil in various electrolytes to obtain titanium oxide layers with different morphologies. Scanning electron microscopy revealed the formation of well-ordered hexagonal TNTs with diagonals in the range of 30–95 nm and heights in the range of 3500–4000 nm (35,000–40,000 Å). The electrochemical measurements performed in 3.5% NaCl and Ringer's solution confirmed a more positive open-circuit potential, a lower impedance, a higher electrical conductivity, and a higher corrosion rate of hTNTs compared to the compact TiO2. The data revealed a major drop in the impedance modulus of hTNTs, with a diagonal of 46 ± 8 nm by 97% in 3.5% NaCl and 96% in Ringer's solution compared to the compact TiO2. Nanoindentation tests revealed that the mechanical properties of the hTNTs were influenced by their diagonal size, with decreasing hardness and Young's modulus observed with an increasing diagonal size of the hTNTs, accompanied by increased plastic deformation. Overall, these findings suggest that hTNTs exhibit promising structural and electrochemical properties, making them potential candidates for various applications, including biosensor platforms. [ABSTRACT FROM AUTHOR]

This paper describes the process to obtain ceramic nanotubes from titanium dioxide, alumina and yttrium oxide by a feasible, replicable and reliable technology, including three stages, starting from an electrospinning process of poly(methyl methacrylate) solutions. A minimum diameter of 0.3 μm was considered optimal for PMMA nanofibers in order to maintain the structural stability of covered fibers, which, after ceramic film deposition, leads to a fiber diameter of 0.5–0.6 μm. After a chemical and physical analysis of the stages of obtaining ceramic nanotubes, in all cases, uniform deposition of a ceramic film on PMMA fibers and, finally, a uniform structure of ceramic nanotubes were noted. The technological purpose was to use such nanotubes as ingredients in screen-printing inks for electrochemical sensors, because no study directly targeted the subject of ceramic nanotube applications for printed electronics to date. The printing technology was analyzed in terms of the ink deposition process, printed electrode roughness vs. type of ceramic nanotubes, derived inks, thermal curing of the electrodes and the conductivity of electrodes on different support (rigid and flexible) at different curing temperatures. The experimental inks containing ceramic nanotubes can be considered feasible for printed electronics, because they offer fast curing at low temperatures, reasonable conductivity vs. electrode length, good printability on both ceramic or plastic (flexible) supports and good adhesion to surface after curing. [ABSTRACT FROM AUTHOR]

The development of hemocompatible biomaterials with antithrombogenic surface coatings remains a challenge in cardiovascular applications. There is interest in negatively charged surfaces that inhibit thrombus formation through electrostatic repulsion between the biomaterial surface and negatively charged platelets. Hence, the present study investigated the influence of electrical polarization on the thrombogenicity of titania nanotubes (TNT), which are promising candidates for inhibiting thrombogenicity via surface modification. TNTs were formed on commercially pure titanium plate by the electrochemical anodization technique using platinum as a counter electrode at 60 V for 24 h with two kinds of electrolytes (hydrofluoric acid diluted with dimethyl sulfoxide [D‐TNT] or ethylene glycol [E‐TNT]) followed by an annealing at 540°C for 3 h in air. Both TNTs were mixture of anatase and rutile, and the D‐TNT had a diameter of 108.76 ± 2.55 nm and the E‐TNT, 53.833 ± 2.42 nm. The TNTs were electrically polarized at 100 V of DC field and 400°C for 1 h. Water contact angle measurements showed that the non‐polarized (0‐) TNT surface was hydrophilic whereas the positively (P‐) or negatively (N‐) polarized TNT surfaces showed high‐hydrophilicity. Antithrombogenicity was evaluated using the thrombus coverage area ratio (TCAR) after soaking the TNTs in bovine whole blood. The TCARs for 0‐polarized E‐ and D‐TNTs were 5.30 ± 4.34% and 36.3 ± 5.8% and for P‐polarized E‐TNT and D‐TNT were 1.50 ± 0.77% and 2.76 ± 1.07%, whereas no thrombus formation (0 ± 0%) for N‐polarized E‐TNT and very few thrombus formation (0.12 ± 0.22%) for N‐polarized D‐TNT. The electrostatic repulsion between the N‐polarized E‐TNTs and platelets completely inhibits thrombus formation, which cannot be achieved by the nanomorphology and high‐hydrophilicity of other TNTs. Hence, N‐TNTs formed by electrical polarization are potential candidates for cardiovascular devices, such as artificial heart valves with long‐term hemocompatibility. [ABSTRACT FROM AUTHOR]

NO2 is a prevalent environmental pollutant, and its reaction with water produces nitric acid, which is one of the main factors contributing to the degradation of books and paper. Therefore, it is crucial to develop a real-time monitoring system for NO2 gas content in the air and establish timely response measures to delay book aging and provide effective protection. In this study, TiO2 nanotubes (NTs) were fabricated using the anodic oxidation method, followed by the preparation of TiO2 NT/MoS2 composites through hydrothermal synthesis. It was observed that flaky MoS2 is attached to the surface of TiO2 nanotubes, forming aggregated structures resembling flower balls. The TiO2 NT/MoS2 nanocomposites were found to exhibit a rapid response with a 5 s response time and an 80 s recovery time towards 367 ppm NO2 at 260 °C. The gas response to 100 ppm NO2 vapor was 3.3, which is higher than all the other gases under the same concentration. Our experimental results demonstrate that compared to pure TiO2 NTs, TiO2 NT/MoS2 composites exhibit a larger specific surface area along with higher sensitivity and faster response times towards various concentrations of NO2 gas. [ABSTRACT FROM AUTHOR]

In this study, two distinct photocatalysts, namely tin(IV)porphyrin-sensitized titanium dioxide nanotubes (SnP-TNTs) and titanium dioxide nanofibers (TNFs), were synthesized and characterized using various spectroscopic techniques. SnP-TNTs were formed through the hydrothermal reaction of NaOH with TiO2 (P-25) nanospheres in the presence of Sn(IV)porphyrin (SnP), resulting in a transformation into Sn(IV)porphyrin-imbedded nanotubes. In contrast, under similar reaction conditions but in the absence of SnP, TiO2 (P-25) nanospheres evolved into nanofibers (TNFs). Comparative analysis revealed that SnP-TNTs exhibited a remarkable enhancement in the visible light photodegradation of model pollutants compared to SnP, TiO2 (P-25), or TNFs. The superior photodegradation activity of SnP-TNTs was primarily attributed to synergistic effects between TiO2 (P-25) and SnP, leading to altered conformational frameworks, increased surface area, enhanced thermo-chemical stability, unique morphology, and outstanding visible light photodegradation of cationic methylene blue dye (MB dye). With a rapid removal rate of 95% within 100 min (rate constant = 0.0277 min−1), SnP-TNTs demonstrated excellent dye degradation capacity, high reusability, and low catalyst loading, positioning them as more efficient than conventional catalysts. This report introduces a novel direction for porphyrin-incorporated catalytic systems, holding significance for future applications in environmental remediation. [ABSTRACT FROM AUTHOR]

In this research, TiO2 nanotubes (NTs) were produced by electrochemical anodization of a Ti substrate where different NH4F wt.% in the electrolyte was added. NTs with diameter of 65–90 nm and 3.3–4.9 µm length were obtained and sensitized with binary cadmium chalcogenides nanoparticles, CdS and CdSe, by successive ionic layer adsorption and reaction method (SILAR). Additionally, both anions S and Se were deposited onto Cd, labeled as CdSSe and CdSeS, to evaluate the effect of the deposition order of the anion from the precursor solution to form cadmium chalcogenides. The structural, optical, and electrochemical performance were analyzed through the SEM, XRD, XPS, UV-VIS, lineal voltammetry and chronoamperometry characterizations. The increase of NH4F wt.% from 1.5% to 4.5% produced a decrement of the diameter and length attributed to the fluoride ions concentration causing solubility of the NTs. XRD confirmed the TiO2 anatase and hexagonal CdS structures. From the EDS and XPS results, the presence of small amount of Se in the sensitized samples demonstrated the doping effect of Se instead of forming ternary semiconductor. With the sensitization of the TiO2 NTs with the nanoparticles, an improved hydrogen generation was observed (reaching 1.068 mL h−1 cm−2) in the sample with CdSSe. The improvement was associated to a synergetic effect in the light absorption and higher cadmium chalcogenide amount deposited when sulfur ions were deposited before selenium. [ABSTRACT FROM AUTHOR]

Abstract The development of hemocompatible biomaterials with antithrombogenic surface coatings remains a challenge in cardiovascular applications. There is interest in negatively charged surfaces that inhibit thrombus formation through electrostatic repulsion between the biomaterial surface and negatively charged platelets. Hence, the present study investigated the influence of electrical polarization on the thrombogenicity of titania nanotubes (TNT), which are promising candidates for inhibiting thrombogenicity via surface modification. TNTs were formed on commercially pure titanium plate by the electrochemical anodization technique using platinum as a counter electrode at 60 V for 24 h with two kinds of electrolytes (hydrofluoric acid diluted with dimethyl sulfoxide [D‐TNT] or ethylene glycol [E‐TNT]) followed by an annealing at 540°C for 3 h in air. Both TNTs were mixture of anatase and rutile, and the D‐TNT had a diameter of 108.76 ± 2.55 nm and the E‐TNT, 53.833 ± 2.42 nm. The TNTs were electrically polarized at 100 V of DC field and 400°C for 1 h. Water contact angle measurements showed that the non‐polarized (0‐) TNT surface was hydrophilic whereas the positively (P‐) or negatively (N‐) polarized TNT surfaces showed high‐hydrophilicity. Antithrombogenicity was evaluated using the thrombus coverage area ratio (TCAR) after soaking the TNTs in bovine whole blood. The TCARs for 0‐polarized E‐ and D‐TNTs were 5.30 ± 4.34% and 36.3 ± 5.8% and for P‐polarized E‐TNT and D‐TNT were 1.50 ± 0.77% and 2.76 ± 1.07%, whereas no thrombus formation (0 ± 0%) for N‐polarized E‐TNT and very few thrombus formation (0.12 ± 0.22%) for N‐polarized D‐TNT. The electrostatic repulsion between the N‐polarized E‐TNTs and platelets completely inhibits thrombus formation, which cannot be achieved by the nanomorphology and high‐hydrophilicity of other TNTs. Hence, N‐TNTs formed by electrical polarization are potential candidates for cardiovascular devices, such as artificial heart valves with long‐term hemocompatibility.

[Display omitted] • Using a promising one-step vacuum space confined with carbon-coated tri-doped reaction method. • A unique novel core/shell structure comprises C N S-TiO 2 nanotubes and N S carbon coating. • Stable nitrogen, carbon and sulfur doping, and cocatalyst have synergistic effects. • Under simulated sunlight and visible light conditions, the photocurrent exhibited an increase of 18.3 times and 32.8 times, respectively. • The photoelectrocatalyst was recyclable and had excellent water splitting performance. The integration of non-metallic doping and carbon coating for TiO 2 -based photoelectrocatalysts can be recognized as a promising strategy to enhance their hydrogen production performance. To this end, this study explored the carbon coating engineering to induce stable multi-element doping with an aim to develop high-performance TiO 2 nanotube array-based photoelectrocatalysts. The resulting structures consisted of carbon–nitrogen-sulfur-tri-doped TiO 2 nanotube arrays with a nitrogen-sulfur-codoped carbon coating (C N S-TNTA/N S C). The fabrication process involved a one-step, low-cost strategy of the carbon-coated tridoped reaction confined in vacuum space, utilizing polymer thiourea sealed in a controlled environment. Compared the photocurrent density of C N S-TNTA/N S C with pristine TNTA, the photocurrent enhancement of approximately 18.3-fold under simulated sunlight and a remarkable increase of 32.8-fold under simulated visible light conditions. The enhanced photocatalytic activity under visible light was ascribed to two factors: First, C, N, and S tri-doping and Ti3+ created a diverse array of impurity energy levels within the band gap, which synergistically narrowed the band gap and further enhanced response to the visible light range. Second, the presence of a carbon coating shell doped with N and S can greatly promote electron transfer and efficient electron-hole pair separation. This study could provide significant insights concerning the design of sophisticated photoanodes. [ABSTRACT FROM AUTHOR]

This study shows that the simple approach of keeping anodic TiO2 nanotubes at 70 °C in ethanol for 1 h results in improved photoelectrochemical water splitting activity due to initiation of crystallization in the material amplified by the light‐induced formation of a Ti3+−Vo states under UV 365 nm illumination. For the first time, the light‐induced Ti3+−Vo states are generated when oxygen is present in the reaction solution and are stable when in contact with air (oxygen) for a long time (two months). We confirmed here that the amorphous or nearly amorphous structure of titania supports the survival of Ti3+ species in contact with oxygen. It is also shown that the ethanol treatment substantially improves the morphology of the titania nanotube arrays, specifically, less surface cracking and surface purification from C‐ and F‐based contamination from the electrolyte used for anodizing. [ABSTRACT FROM AUTHOR]

A self-organized TiO2 nanotubes were fabricated via anodization on Titanium substrate and loaded with dispersed platinum nanoparticles using electrodeposition method. The effect of electrodeposited Pt NPs (100 s, 200 s, 300 s, 600 s) on TiO2 nanotubes on their photocatalytic activities for amido black (AB) dye degradation was studied. Morphological characterizations showed a highly ordered nanotubular TiO2 structure with 15 μm of length and 100 nm of diameter using Scanning Electron Microscopy (SEM) and Transmission Electron Microscopy (TEM) technics. Optical characterizations such as photoluminescence and diffuse reflectance spectroscopy proved the charges exchange between metal NPs and the semiconductor. The successful depositions of Pt on to the surface of TiO2-NTs contributed for the improved photocatalytic activity compared to the pure sample, due to the greater the work function of platinum nanoparticle, which further anchored the separation of photogenerated electron–hole pairs. It was found that the sample Pt/TiO2-NTs with 200 s of Pt deposition time offered the highest photocatalytic performance, this sample resulted 97% degradation after 90 min under UV irradiation. Due to the plasmonic effect of Pt nanoparticles we obtained an intensification in the photocatalytic activity. Kinetic studies demonstrated that the apparent first-order kinetics for the corresponding photocatalytic reaction shows that Pt/TiO2 NTs is one of the best photocatalyst for dye degradation. Furthermore, quenching studies were performed and shows that hydroxyl radicals (OH°) and superoxide free radicals (O2°) were the primary and secondary reactive species during photo-degradation. [ABSTRACT FROM AUTHOR]

The current research aims to elucidate the influence of reduction process of TiO2 nanostructures on the surface properties of a bioinspired Ti modified implant, considering that the interface between a biomaterial surface and the living tissue plays an important role for this interaction. The production of reduced TiO2 nanotubes (RNT) with lower band gap is optimized and their performance is compared with those of simple TiO2 nanotubes (NT). The more conductive surfaces provided by the presence of RNT on Ti, allow a facile deposition of silk fibroin (SF) film using the electrochemical deposition method. This hybrid film is then functionalized with ZnO nanoparticles, to improve the antibacterial effect of the coating. The modified Ti surface is evaluated in terms of surface chemistry, morphology and roughness, wettability, surface energy, surface charge and antibacterial properties. Surface analysis such as SEM, AFM, FTIR and contact angle measurements were performed to obtain topographical features and wettability. FT‐IR analysis confirms that SF was effectively attached to TiO2 nanotubes surfaces. The electrochemical deposition of SF and SF‐ZnO reduced the interior diameter of nanotubes from ~85 nm to approx. 50–60 nm. All modified surfaces have a hydrophilic character. [ABSTRACT FROM AUTHOR]

The atomic layer deposition method allows for the production of a thin film with a high aspect ratio on the uneven surface of titanium dioxide nanotubes TiO2(Nt). A modified BiFeO3/TiO2(Nt)/Ti (BFOT) structure with controllable electrical characteristics was obtained. BFOT possesses both ferroelectric and semiconductor properties with nonlinear conductivity dependent on the magnitude and duration of the voltage supply. Analysis of the temperature dependence of charge variation showed leakage currents in the BFOT structure due to the capture and release of charge carriers from defect levels. Surface modification of nanotubes with the multiferroic BiFeO3 allows for the creation of semiconductors with adaptive functional properties. [ABSTRACT FROM AUTHOR]

The capacitive deionization (CDI) technique is considered a promising eco-friendly desalination method due to its high energy efficiency, ease of operation, and simplistic electrode regeneration capability. Thus, significant research is focused on developing highly efficient electrode materials with high electrochemical stability and salt electro-adsorption capacity (Sc) behavior during operation because these are the governing factors in examining the measured activity of fabricated CDI cells. In this manuscript, we report the synthesis of hydrogenated titanium nanotubes@spongy activated carbon (HTiO 2 NTs@SAC) using pyrolysis and hydrothermal processes. The SAC is synthesized by the pyrolysis of spongy loofa in an inert atmosphere and further hydrothermally activating it in an aqueous potassium hydroxide solution. The hydrothermal process activates and enhances the hydrophilicity of SAC. HTiO 2 is synthesized electrochemically at 20 V in 0.1 M perchloric acid. Such HTiO 2 NTs@SAC configuration can provide excellent pathways to increase ion adsorption and improve the kinetics of charge transfer by enhancing the contact between the electrolyte and electrode at the interface. It is found that HTiO 2 NTs@SAC has a specific capacitance (Cs) of 385.7 F g−1 compared with 332.7 F g−1 for SAC. The salt electrosorption capacity (Sc) of HTiO 2 NTs@SAC electrode material is found to be 24.90 mg g−1 in 250 μS cm −1 saline solution at 1.2 V, which is much higher than the values obtained for SAC (9.8 mg g−1). HTiO 2 NTs@SAC has also shown an antimicrobial effect toward gram-negative bacteria and exhibited good performance in the supercapacitor application, wherein HTiO 2 NTs@SAC showed a higher Cs (505.55 F g−1) than SAC (380 F g−1) at 1 A g−1. Thus, we demonstrate that the prepared composite can be used as an energy storage material, an antibacterial material, and a CDI electrode in the CDI technology. [ABSTRACT FROM AUTHOR]

In this work, we synthesized TiO 2 nanotube films (TiO 2 -NTFs) photo-decorated with Ag nanoparticles for their application in Surface-Enhanced Raman Scattering. In situ growth of Ag nanoparticles was performed through the exposure of anodic TiO 2 -NTFs to UVC radiation following their pretreatment in an AgNO 3 aqueous solution. High nanoparticle surface densities, with uniform coverage on the film surface, and controllable size, were prepared by regulating the UVC exposure time and AgNO 3 concentration. Ag nanoparticles nucleation and growth also take place along the tubes, including at the bottoms. The evidence obtained also indicates that a high enough AgNO 3 concentration inhibits the well-known water-assisted crystallization mechanism, typically promoted when TiO 2 -NTFs are exposed for prolonged times in aqueous media. The performance of the photo-decorated films in Surface-Enhanced Raman Scattering shows that the presence of Ag nanoparticles plays a key role, and both the nanoparticle surface density and size must be regulated to promote a large number of hot-spots. [ABSTRACT FROM AUTHOR]

Ti and their alloys are commonly used metallic implants due to their good bio-activity. Post-surgery reflects inferior osseointegration that makes the material unhealthy in the long run after surgery. In this regard, surface characteristic remains one of the most trivial and incurable problems for hard tissue application. In the present study, Nano-Dicalcium Phosphate Dihydrate (DCPD) Coatings were deposited over anodized TiO 2 Nanotubes and its structural, surface and in-vitro study has been done. Surface transitions from the contact angle analyser reveal hydrophilic to super-hydrophilic surfaces have been achieved over Ti6Al4V alloy. The highest absorbance value has been observed on TTOAD compared to TD in both 24 h and 48 h. FESEM Mapping and EDS unveil that the distribution of elements is not homogenous entirely. However, the AFM result reveals that the distribution of an ex-situ deposited layer is enriched in Calcium-Phosphorus elements and has distinct irregular topography. Besides more surface roughness value has been revealed in TTOAD surface. Optical density (O.D.) value at 570 nm with ∼ 1.09 O.D. at 24 h and ∼1.3 O.D. at 48 h was obtained on the TTOAD specimen reflecting the best cell proliferation of MG-63 compared to TD. In addition, superhydrophilicity with ∼8.5° contact angle was gained at TTOAD compared to TD and TTOCD specimens. [ABSTRACT FROM AUTHOR]

This work examines the cooperative effect between Zr doping and oxygen vacancy engineering in anodized TiO2 nanotubes (TNTs) for enhanced oxygen reduction reactions (ORRs). Zr dopant and annealing conditions significantly affected the electrocatalytic characteristics of grown TNTs. Zr doping results in Zr4+ substituted for Ti4+ species, which indirectly creates oxygen vacancy donors that enhance charge transfer kinetics and reduce carrier recombination in TNT bulk. Moreover, oxygen vacancies promote the creation of unsaturated Ti3+(Zr3+) sites at the surface, which also boosts the ORR interfacial process. Annealing at reductive atmospheres (e.g., H2, vacuum) resulted in a larger increase in oxygen vacancies, which greatly enhanced the ORR activity. In comparison to bare TNTs, Zr doping and vacuum treatment (Zr:TNT–Vac) significantly improved the conductivity and activity of ORRs in alkaline media. The finding also provides selective hydrogen peroxide production by the electrochemical reduction of oxygen. [ABSTRACT FROM AUTHOR]

The present study investigated the application of photocatalytic process using TiO 2 nanotubes (NTs) photocatalyst as an effective pre-treatment method for palm kernel expeller (PKE) in increasing its biodegradability to enhance the microalgal hydrogen production via dark fermentation. A series of TiO 2 NTs photocatalysts were synthesized via employing electrochemical anodization of Ti foil at various voltages each in different types of electrolytes (choline chloride-ethylene glycol (ChCl-EG), choline chloride-urea (ChCl-U), choline chloride-glycerol (ChCl-Gly)). Increasing trend of average NTs diameters at 26.14 ± 1.30, 73.01 ± 1.94 and 122.00 ± 13.32 nm was observed for 25, 30 and 35 V in synthesizing TiO 2 NTs using suitable ChCl-EG electrolyte, respectively. The high 35 V had resulted in noticeable pore ruptures within this TiO 2 NTs photocatalyst. The PKE pre-treated by TiO 2 NTs photocatalyst anodized at optimum 30 V in ChCl-EG electrolyte had demonstrated the highest releases of biochemical oxygen demand (BOD 5) and soluble chemical oxygen demand (SCOD) concentrations at 594 and 607 mg/L, respectively. Moreover, the microalgal efficiency of BOD 5 conversion and hydrogen yield were also consistently maintained from third cycle of TiO 2 NTs photocatalyst's reutilizations, signifying the stability of TiO 2 NTs photocatalyst. [Display omitted] • Anatase phase TiO 2 NTs photocatalyst to pre-treat palm kernel expeller (PKE). • Photocatalytic pre-treated PKE exhibited improved biodegradable organic matter. • TiO 2 NTs in ChCl-EG at 30 V showed enhanced microalgal hydrogen production. • TiO 2 NTs was stable and reusable in releasing biodegradable organics from PKE. [ABSTRACT FROM AUTHOR]

In this research, the effect of metal electrodes and crystalline phase on gas detection of titanium dioxide (TiO 2) nanotube-based hydrogen (H 2) sensors was investigated. TiO 2 nanotubes were produced using glycerol-based electrolyte and annealed at 300 °C and 700 °C to change the anatase and rutile crystalline phases, respectively. TiO 2 nanotubes were coated by platinum (Pt), palladium (Pd), gold (Au) and silver (Ag) electrodes to fabricate metal/TiO 2 nanotubes Ti H 2 sensor devices and then the current-voltage (I–V) characteristics were investigated at room temperature. The structural properties of TiO 2 nanotubes were characterized by SEM, FE-SEM, XRD, and Raman techniques. The H 2 detection properties of the sensors were examined at the 1000 ppm - 5% H 2 concentration range. The crystal structure and metal electrodes are the main factors that affect the H 2 sensing properties of TiO 2 nanotube-based sensors. The effect of crystal forms on sensitivity was not the same as for metal electrodes. The underlying sensing mechanisms for different types of metal electrodes and crystal structures are discussed and the relevance of their sensing performance to nanotubes and electronic properties is investigated. In addition, discussion of each metal electrode and crystal structure will make important contributions to the development of H 2 sensors. The Pd-coated device annealed at 700 °C showed the best detection performance. • The synthesis of TiO 2 nanotubes by gylcerol-based anodization method. • The mean length and diameter of the nanotubes are 1.67 μm and 169 nm respectively. • The H 2 sensors were fabricated with various metal electrodes and crystal structure. • The highest H 2 sensor sensitivity was obtained with the Pd coated rutile form sensor. • The best sensor response (I H2 /I air) value was measured as 15118.7 for Pd-700 °C. [ABSTRACT FROM AUTHOR]

[Display omitted] Advanced oxidation processes (AOPs) can directly degrade and mineralize organic pollutants (OPs) in water by generating reactive oxygen species with strong oxidizing ability. The development of advanced electrode materials with high catalytic performance, low energy consumption, no secondary pollution, and long lifespan has become a challenge that must be addressed in this field. A heterojunction catalyst loaded with Co 3 O 4 on TDNAs (Co 3 O 4 /RTDNAs) was designed and constructed by a simple and efficient pyrolysis (Co 3 O 4 /TDNAs) and electrochemical reduction. Co 3 O 4 can be uniformly distributed on the inner wall and surface of the TiO 2 nanotubes, enhancing the specific surface area while forming a tight conductive interface with TiO 2. This facilitates rapid transmission of electrons, thereby assisting Co 3 O 4 in quickly activating PS to form reactive oxygen species. The Ti3+ and Ov generated in Co 3 O 4 /RTDNAs can significantly improve the electrocatalytic degradation of OPs. Also, the interface formed by Co 3 O 4 and RTDNAs will effectively suppress Co2+ leakage, thereby reducing the risk of secondary pollution. When the reaction conditions were 1 mM PMS (PDS) and a current density of 5 mA/cm2 in the EA-PMS (PDS)/Co 3 O 4 /RTDNA system, 30 mg/L TC can achieve 83.24 % (81.89 %) removal in 120 min, with very low cobalt ion leaching, while the energy consumption was reduced significantly. Therefore, EA-PS/Co 3 O 4 /RTDNA system has strong stability and a high potential for treating the OPs in AOPs. [ABSTRACT FROM AUTHOR]

Titanium dioxide nanotubes (TNT) have been extensively studied because of their unique properties, which make such systems ideal candidates for biomedical application, especially for the targeted release of drugs. However, knowledge about the properties of TiO2 nanotubes with typical dimensions of the order of the nanometer is limited, especially concerning the adsorption of molecules that can be potentially loaded in actual devices. In this work, we investigate, by means of simulations based on hybrid density functional theory, the adsorption of Vitamin C molecules on different nanotubes through a comparative analysis of the properties of different structures. We consider two different anatase TiO2 surfaces, the most stable (101) and the more reactive (001)A; we evaluate the role of the curvature, the thickness and of the diameter as well as of the rolling direction of the nanotube. Different orientations of the molecule with respect to the surface are studied in order to identify any trends in the adsorption mechanism. Our results show that there is no preferential functional group of the molecule interacting with the substrate, nor any definite spatial dependency, like a rolling orientation or the concavity of the nanotube. Instead, the adsorption is driven by geometrical factors only, i.e., the favorable matching of the position and the alignment of any functional groups with undercoordinated Ti atoms of the surface, through the interplay between chemical and hydrogen bonds. Differently from flat slabs, thicker nanotubes do not improve the stability of the adsorption, but rather develop weaker interactions, due to the enhanced curvature of the substrate layers. [ABSTRACT FROM AUTHOR]

The effects of TiO2 nanotube (TNT) and reduced graphene oxide (rGO) deposition onto titanium, which is widely used in dental implants, on Streptococcus mutans (S. mutans) and preosteoblastic cells were evaluated. TNTs were formed through anodic oxidation on pure titanium, and rGO was deposited using an atmospheric plasma generator. The specimens used were divided into a control group of titanium specimens and three experimental groups: Group N (specimens with TNT formation), Group G (rGO-deposited specimens), and Group NG (specimens under rGO deposition after TNT formation). Adhesion of S. mutans to the surface was assessed after 24 h of culture using a crystal violet assay, while adhesion and proliferation of MC3T3-E1 cells, a mouse preosteoblastic cell line, were evaluated after 24 and 72 h through a water-soluble tetrazolium salt assay. TNT formation and rGO deposition on titanium decreased S. mutans adhesion (p < 0.05) and increased MC3T3-E1 cell adhesion and proliferation (p < 0.0083). In Group NG, S. mutans adhesion was the lowest (p < 0.05), while MC3T3-E1 cell proliferation was the highest (p < 0.0083). In this study, TNT formation and rGO deposition on a pure titanium surface inhibited the adhesion of S. mutans at an early stage and increased the initial adhesion and proliferation of preosteoblastic cells. [ABSTRACT FROM AUTHOR]

Titanium dioxide with suitable band edges is one of promising photocatalysts for water splitting. Nanotubes with one-dimensional structure can induce efficient charge transfers and hollow centers can provide large surface area for surface reactions. Modifying Ti foils for anodization can enhance light utilization of TiO 2 nanotube photoelectrodes. In this work, it is firstly to fabricate TiO 2 nanotube photoelectrodes on acid-etched Ti foils by anodization (MNT) for photoelectrochemical catalyzing water splitting. Different acid-etching durations are applied on Ti foils to induce various rugged surfaces. The resulting photoelectrodes present largely enhanced light utilization than that fabricated by the pristine Ti foil. The anodization duration is also optimized to find suitable lengths of MNT. The smallest overpotential of 524.7 mV at 10 mA/cm2 and Tafel slope of 167 mV/dec are obtained for the optimal MNT photoelectrode. The TiO 2 nanotubes grown on the pristine Ti foil shows the overpotential of 679.3 mV at 10 mA/cm2 and Tafel slope of 285 mV/dec. This result opens a blueprint for raising the photocatalytic ability by simply modifying the surface property of the conductive substrate. Other modifications may be applicable to enhance the roughness of Ti foils for growing more efficient MNT array as photocatalysis of water splitting. [Display omitted] • TiO 2 nanotube photoelectrodes are fabricated on acid-etched Ti foils by anodization. • Different acid-etching duration is used on Ti foil to induce various rugged surface. • Anodization duration is optimized to find the suitable lengths of TiO 2 nanotubes. • Smaller overpotential of 524.7 mV at 10 mA/cm2 and Tafel slope of 167 mV/dec are got. • High light absorbance and small charge transfer resistance are got for modified tube. [ABSTRACT FROM AUTHOR]

Photoelectrochemical, structural, and electrocatalytic properties of titanium dioxide (TiO2) nanotubes obtained by the anodization of titanium with subsequent thermal treatment in air or hydrogen were studied. The heat treatment of TiO2 nanotubes in hydrogen was found to have no effect on the morphology and phase composition of the resultant TiO2 electrodes. However, such treatment led to a high concentration of defect states in the TiO2 crystal lattice due to reductive doping accompanied by the conversion of Ti4+ to Ti3+. The rise in the defectivity diminished the overpotential for oxygen electroreduction at an electrode made from titanium dioxide nanotubes annealed in hydrogen compared to such an electrode annealed in air. In addition, annealing in hydrogen led to a significant increase in the long-wavelength photocurrent generated under visible light irradiation. [ABSTRACT FROM AUTHOR]

Constructing heterostructures is a promising strategy to improve the photoelectrochemical (PEC) performance of photoanodes in PEC water‐splitting systems. The effect on PEC performance is dependent on the deposition conditions of the overlayer in the heterostructured photoanode. Herein, the deposition condition of the antimony selenide (Sb2Se3) overlayer by adjusting the duty cycle and cycle number during pulse‐reverse electrodeposition. This aims to assess its impact on the PEC characteristics of the Sb2Se3 overlayered titanium dioxide (Sb2Se3/TiO2) nanotube photoanode. Adequate pulse‐off time in the duty cycle ensures sufficient permeation of deposition electrolyte into the inner wall of TiO2 nanotube, leading to uniform Sb2Se3 deposition. On the other hand, an excessive cycle number negatively affects PEC performance, as Sb2Se3 agglomeration blocks the pores of the TiO2 nanotube. Consequently, the Sb2Se3/TiO2 nanotube photoanode, when fabricated with the optimal pulse‐off time and cycle number, exhibits enhanced PEC performance. This is due to efficient charge transfer/separation facilitated by the p–n heterojunction and improved light absorption. These insights offer valuable guidance in choosing the appropriate fabrication processes for heterostructured photoanodes in efficient PEC water‐splitting systems. [ABSTRACT FROM AUTHOR]

Copyright of Journal of Orofacial Orthopedics/Fortschritte der Kieferorthopadie is the property of Springer Nature and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

The geometric and electronic properties of the double-walled nanotubes (DWNTs), constructed by the two coaxial single-walled nanotubes (SWNTs) rolling the hexagonal titanium dioxide (TiO2) nanosheet along with the armchair (ac-) and the zigzag (zz-) directions, have been investigated systematically using the methods based on the density functional theory. For the optimized structures, the bandgap values of the TiO2 DWNTs are significantly reduced from that of the constituent SWNTs, falling in the visible light range. Further detailed analysis reveals that the reduction is caused by the band misalignment due to the different curvatures of the inner and outer TiO2 SWNTs. [ABSTRACT FROM AUTHOR]