Ti-based Material Research Articles

Preparation and characterization of mesoporous HA coating with paclitaxel loaded lignin nanospheres on titanium surface

BackgroundPrimary malignant bone tumor is a disease that can lead to death. The usually applied clinical treatment strategy is surgical resection of the primary tumor. However, tumor cells are difficult to clean up, easy to make the tumor recurrence, and the bone defect caused by surgical resection also hindered the postoperative recovery. Materials and methodsHerein, in this work, mesoporous hydroxyapatite (HA) coating with petal-structure was prepared on titanium (Ti) implant surfaces by micro-arc oxidation (MAO) to accelerate the bone growth, and then paclitaxel (PTX) loaded lignin nanospheres were deposited into the HA coatings to get a sustained release for killing residual tumor cells. ResultsThe results showed that many gaps and holes of micro-scale were formed in the petal-structured HA coatings, they worked as traps for the PTX loaded nanospheres to enhance the deposited amount and immobilization stability, playing good role of drug loading platform. The encapsulation of PTX by lignin ensured a lower release rate and a higher sustaining release time when compared with the PTX without encapsulation. In addition, the HA coating with PTX loaded lignin nanospheres showed higher killing effect to tumor cells than to osteoblast. ConclusionThe mesoporous HA coating with paclitaxel loaded lignin nanospheres endowed the titanium surface with good biological property and tumor cell-killing effect, so the obtained Ti-based material had a highly hopeful application as the localized implant for therapy of primary malignant bone tumor.

Four-birds-with-one-stone: A multifunctional Ti-based material for solar-driven water evaporation

Four-birds-with-one-stone: A multifunctional Ti-based material for solar-driven water evaporation

A Novel Two-Dimensional TiClO as a High-Performance Anode Material for Mg-Ion Batteries: A First-Principles Study.

Searching for efficient electrode materials with excellent electrochemical performance is of great significance to the development of magnesium-ion batteries (MIBs). Two-dimensional Ti-based materials are appealing for use in MIBs due to their high cycling capability. On the basis of density functional theory (DFT) calculations, we comprehensively investigate a novel two-dimensional Ti-based material, namely, TiClO monolayer, as a promising anode for MIBs. Monolayer TiClO can be exfoliated from its experimentally known bulk crystal with a moderate cleavage energy of 1.13 J/m2. It exhibits intrinsically metallic properties with good energetical, dynamical, mechanical, and thermal stabilities. Remarkably, TiClO monolayer possesses an ultra-high storage capacity (1079 mA h g-1), a low energy barrier (0.41-0.68 eV), and a suitable average open-circuit voltage (0.96 V). The lattice expansion for the TiClO monolayer is slight (<4.3%) during the Mg-ion intercalation. Moreover, bilayer and trilayer TiClO can considerably enhance the Mg binding strength and maintain the quasi-one-dimensional diffusion feature compared with monolayer TiClO. All these properties indicate that TiClO monolayers can be utilized as high-performance anodes for MIBs.

Decomposition behavior of yttria-stabilized zirconia and its effect on directed energy deposited Ti-based composite material

• The present study focuses on the rule of YSZ nanoparticles in the refined both α and β grains and increased strength of additively manufactured Ti-6Al-4 V (Ti64). • The YSZ nanoparticles decomposed during the deposition process and led to the formation of Y 2 O 3 and some excess oxygen in the Ti64 matrix. • The decrease in the sizes of the prior β grains could be attributed to the increasing amount of dissolved oxygen and yttrium, which promoted constitutional supercooling. • The reduction in the size of the α grains could be ascribed to a shift of the onset of the β → α+β transformation to a higher temperature and shorter time with increasing concentration of dissolved oxygen. • The contributions of the underlying strengthening mechanisms (α grain size, oxygen solid solution, Y 2 O 3 precipitate) for the as-deposited specimens were quantitatively determined. We report on the microstructure and the strengthening mechanisms of additively manufactured parts fabricated by directed energy deposition of Ti-6Al-4V (Ti64) powders blended with yttria-stabilized zirconia (YSZ) nanoparticles. These specimens showed refined microstructures as compared to bare as-deposited Ti64, where the α and columnar prior β grain sizes decreased with increasing YSZ content. The YSZ nanoparticles decomposed during the deposition process and led to the formation of yttrium oxide and some excess oxygen in the Ti64 matrix. The decrease in the sizes of the prior β grains could be attributed to the increasing amount of dissolved oxygen and yttrium, which promoted constitutional supercooling. Furthermore, the reduction in the size of the α grains could be ascribed to a shift of the onset of the β → α+β transformation to a higher temperature and shorter time with increasing concentration of dissolved oxygen. Finally, the contributions of the underlying strengthening mechanisms for the as-deposited specimens were quantitatively determined.

A post-functional Ti-based MOFs composite for selective removal of Pb (II) from water

Lead ions in water have notorious effects on humans and environment. It is important to design an adsorbent with high adsorption capacity and reproducibility for efficiently removing Pb (II)ions from polluted water. Here, a novel Ti-based MOFs material (BDB-MIL-125(Ti)@Fe3O4) was prepared by modifying NH2-MIL-125(Ti) with sulfhydryl and amino groups. Due to the large number of active sites, the maximum Pb (II) adsorption capacity of BDB-MIL-125(Ti)@Fe3O4 was 710.79 mg/g at 25 °C and pH = 6 within 120 min corresponding to a maximum removal rate of 95.68%. The adsorbent also has extremely high selectivity and good cycling adsorption performance. The adsorption isotherms and kinetics agree with the Langmuir and the pseudo-second-order models, indicating that the process was chemisorption. Thermodynamic studies prove that spontaneous processes enhance Pb (II) adsorption at higher temperatures. DFT and FMOs calculations were used to discuss the adsorption mechanism. The sulfhydryl groups on the surface of organic ligands have a stronger affinity for Pb (II).

Application of factor analysis in electron spectrometry (AES, XPS) for materials science

Abstract Electron spectroscopic methods as X-ray photoelectron spectrometry (XPS) and Auger electron spectrometry (AES) are well established in the field of thin-film and surface analysis. In the measured spectral information, always also chemical information on the sample is contained. It is discussed that often chemometrical methods are the only way to extract such (hidden) information from the measured data sets. We demonstrate for AES and XPS measurements, how factor analysis (FA) can help to derive chemical information at Ti-based material developed for body implants. An introduction to the methodology is given, and challenges and restrictions are discussed.

In situ composite of Co-MOF on a Ti-based material for visible light multiphase catalysis: synthesis and the photocatalytic degradation mechanism

A Co-MOF/Ti-based Z-type heterojunction prepared by an in situ growth method exhibits good photocatalytic activity for tetracycline.

Revisited Ti2Nb2O9 as an Anode Material for Advanced Li-Ion Batteries.

Ti2Nb2O9 with a tunnel-type structure is considered as a perspective negative electrode material for Li-ion batteries (LIBs) with theoretical capacity of 252 mAh g-1 corresponding to one-electron reduction/oxidation of Ti and Nb, but only ≈160 mAh g-1 has been observed practically. In this work, highly reversible capacity of 200 mAh g-1 with the average (de)lithiation potential of 1.5 V vs Li/Li+ is achieved for Ti2Nb2O9 with pseudo-2D layered morphology obtained via thermal decomposition of the NH4TiNbO5 intermediate prepared by K+→ H+→ NH4+ cation exchange from KTiNbO5. Using operando synchrotron powder X-ray diffraction (SXPD), single-phase (de)lithiation mechanism with 4.8% unit cell volume change is observed. Operando X-ray absorption near-edge structure (XANES) experiment revealed simultaneous Ti4+/Ti3+ and Nb5+/Nb4+ reduction/oxidation within the whole voltage range. Li+ migration barriers for Ti2Nb2O9 along [010] direction derived from density functional theory (DFT) calculations are within the 0.15-0.4 eV range depending on the Li content that is reflected in excellent C-rate capacity retention. Ti2Nb2O9 synthesized via the ion-exchange route appears as a strong contender to widely commercialized Ti-based negative electrode material Li4Ti5O12 in the next generation of high-performance LIBs.

Imidazolium-based titanosilicate nanospheres as active catalysts in carbon dioxide conversion: Towards a cascade reaction from alkenes to cyclic carbonates

Porous silica-based nanospheres bearing titanium centres as single site were successfully synthesized employing a time- and energy-efficient procedure. The influence of the post-synthesis treatment on the insertion of Ti was investigated via DR UV–Vis and XPS spectroscopy and the titanium content was quantified through ICP-OES analysis. The textural and structural properties of the different solids were evaluated via XRD, TEM and N2 physisorption. The resulting materials were thereafter covalently functionalized with imidazolium chloride, followed by characterization via 29Si and 13C solid-state NMR, N2 physisorption and chemical combustion analysis. The bi-functional catalysts were tested in the challenging conversion of CO2 with cyclohexene oxide to the corresponding cyclic carbonate as well as with various other epoxides with excellent results. The insertion of Ti as single site played a key role substantially improving the activity of the solids. The most active bi-functional material was successfully recovered and reused through multiple cycle without loss of the catalytic activity. Moreover, the cyclohexene epoxidation reaction was tested as well employing the mono-functionalized Ti-based material. The catalytic mixture, composed by the mono-functional and bi-functional solids, was efficiently used to convert the cyclohexene into cyclohexene oxide and subsequently the cyclohexene oxide into the corresponding carbonate thus opening the prospect for a cascade reaction.

Optimizing an Osteosarcoma-Fibroblast Coculture Model to Study Antitumoral Activity of Magnesium-Based Biomaterials.

Osteosarcoma is among the most common cancers in young patients and is responsible for one-tenth of all cancer-related deaths in children. Surgery often leads to bone defects in excised tissue, while residual cancer cells may remain. Degradable magnesium alloys get increasing attention as orthopedic implants, and some studies have reported potential antitumor activity. However, most of the studies do not take the complex interaction between malignant cells and their surrounding stroma into account. Here, we applied a coculture model consisting of green fluorescent osteosarcoma cells and red fluorescent fibroblasts on extruded Mg and Mg–6Ag with a tailored degradation rate. In contrast to non-degrading Ti-based material, both Mg-based materials reduced relative tumor cell numbers. Comparing the influence of the material on a sparse and dense coculture, relative cell numbers were found to be statistically different, thus relevant, while magnesium alloy degradations were observed as cell density-independent. We concluded that the sparse coculture model is a suitable mechanistic system to further study the antitumor effects of Mg-based material.

Pulsed laser–deposited Li2TiO3 thin film electrodes for energy storage

Li2TiO3 (LTO) is a promising Ti-based material showing interesting electrochemical performance, good structural stability, cost-effectiveness, and non-toxic electrode material for energy storage and conversion. In this work, thin films of LTO have been deposited by the pulsed laser deposition (PLD) technique on Au/Ti/SiO2/textured Si multilayer substrates maintained at different temperatures (Ts) in a partial pressure of 0.4 mPa, and the microstructural properties are investigated. The as-deposited films are textured and contain TiO2 impurities. The LTO thin films grown at Ts of 600 °C are observed to be phase pure with a predominant (002) orientation related to the β-Li2TiO3 phase with C2/c symmetry. As electrodes for lithium microbatteries, LTO thin films delivered a specific discharge capacity of 46 μAh cm−2 μm−1 in the voltage range 0.0–1.0 V vs. Ag/AgCl and retained 91% capacity after 30 discharge cycles; as electrodes for supercapacitors, LTO thin films displayed a specific capacitance of 283 mF cm−2 at a current density of 1 mA cm−2 and retained 94% capacitance over 1000 cycles. The dual nature of the films demonstrates that the LTO films are suitable electrodes for supercapattery application.

Design TiZrCuNi filler materials for vacuum brazing TA15 alloy

TA15 alloy with near α microstructure offers excellent high temperature mechanical properties for future gas turbine blades. To developing for the thin-wall and complex structure of this material, brazing is preferred. However, a new brazing material and process are required. In this study, a new theoretical modeling approach for designing Ti-based filler material for TA15 is presented by simulation on the bond strength in the crystal unit for the brazing filler material (BFM). The BFM chemical composition was determined as Ti-(17∼19)Zr-15Cu-15Ni wt.% to balance its strength, the toughness and relative lower melting temperature for TA15. All the fracture happened in the matrix rather than the brazing joints. It means that the strength of the brazed TA15 joint at room temperature was at least as strong as that of the matrix. Furthermore, under its service temperature (600℃), the strength of the brazing joint maintained almost 70 % of strength. The high joint strength and the ductile connection were attributed to the formed Widmanstätten structure and the sufficient diffusion of Cu and Ni solutes from the BFM across the interface. No intermetallics compound was formed in the joint. This model is established to optimizing a Ti-based filler material for achieving the excellent properties of brazed joints.

Corrosion behaviors and mechanisms of in-situ Ti-based MGMCs in chloride-containing and chloride-free solutions

The corrosion behavior of Ti62Zr12V13Cu4Be9 metallic glass matrix composites (MGMCs) in chloride-containing (NaCl and HCl) and chloride-free (NaOH and H2SO4) solutions was studied. As a result, Ti62Zr12V13Cu4Be9 MGMCs exhibits better corrosion resistance in chloride-free solutions due to the formation of oxide layer. In comparison, the oxide layer formed in NaOH solution is superior to that formed in H2SO4 solution according to the analysis results of XPS and EIS. The irregularity of elemental and phase distribution in this Ti-based MGMCs material is considered the driving force of the corrosion process. With the inclusion of other factors such as the different pH values and the cathodic reaction, rather reasonable interpretation about the difference of corrosion behaviors of Ti-based MGMCs samples in various media is proposed.

Hazard assessment for a Ti-based nano-additived material: from core-shell production to final part

Hazard assessment for a Ti-based nano-additived material: from core-shell production to final part

Metal-Oxide-Supported Ir-Decorated Electrocatalysts for Polymer Electrolyte Membrane Water Electrolysis

Introduction Since polymer electrolyte membrane water electrolysis (PEMWE) is similar in cell structure to polymer electrolyte fuel cells (PEFC), technologies used for PEFCs can be applied to PEMWEs. However, Pt electrocatalysts supported on carbon black (Pt/C) typically used for PEFCs cannot be applied under a high potential up to 2.0V [1]. Here, we apply SnO2 and titanium as alternative support materials. SnO2 may be promising as an anode electrocatalyst support material since it has relatively high electronic conductivity and stability against a high potential, among various metal oxides [2 ,3 ]. The top surface of metallic titanium is naturally oxidized to form stable titanium oxide, so that titanium supports may exhibit high durability under the strongly-acidic PEMWE condition [4]. In this study, we prepare the iridium-decorated SnO2/VGCF electrocatalysts (IrO2/Nb-SnO2/VGCF). Furthermore, by making such Ti sheet acting as the gas diffusion layer (GDL) and current collector, we prepare a GDL-integrated PEMWE electrode consisting of Ir electrocatalyst and Ti-based catalyst support (Ir/Ti). Experimental Sn0.98Nb0.02O2/VGCF was prepared via an ammonia co-precipitation method. IrO2 nanoparticles were decorated on Sn0.98Nb0.02O2/VGCF by evaporating the aqueous solution mixture containing Sn0.98Nb0.02O2/VGCF and H2IrCl6.nH2O while stirring, followed by heat treatment at 440°C in air. The Ti sheet was etched with 1M NaOH solution at 60°C for 1 hour, followed by heat treatment at 400°C in 5%H2-N2 for 30 minutes. Ir nanoparticles were decorated on the NaOH-etched Ti sheet by the arc plasma deposition (APD). The microstructure of the IrO2/Nb-SnO2/VGCF and the Ir/Ti sheet was observed by SEM, STEM, and TEM. Electrochemical measurements were made for the half cell and the single cell. Results and discussion We prepared IrO2/Sn(Nb)/VGCF with IrO2 loading of 23.6wt.%. Figure 1 shows the micrograph of the IrO2/Nb-SnO2/VGCF electrocatalyst. The micrograph indicates that Ir (or IrO2) nanoparticles have particle size of 1 to 3nm in diameter. I-V characteristics and durability of the MEA made with the IrO2/Sn(Nb)O2/VGCF electrocatalyst were evaluated. The MEA exhibited low activation overvoltage, but still with high IR loss and poor durability Figure 2 shows the STEM image of the Ir/Ti sheet after 2000 pulses of the APD with the Ir loading of 0.086mg/cm2, showing Ir particles of 1 to 2 nm on the etched Ti-based material. I-V characteristics of the MEA made with the Ir/Ti with the oxidized Ti surfaces were evaluated. The Ir/Ti MEA exhibited higher performance than that of the IrO2/Sn(Nb)O2/VGCF electrocatalyst despite very low Ir loading, indicating that the Ir/Ti MEA could be of interest for PEMWE applications.

Superhydrophilic and underwater superoleophobic Ti foam with fluorinated hierarchical flower-like TiO2 nanostructures for effective oil-in-water emulsion separation

In this work, a superhydrophilic Ti foam was designed and fabricated by applying a novel one-step hydrothermal approach to achieve highly efficient oil in water emulsion separation. Attributed to the synergistic effect of the surface roughness constructed by hierarchical flower-like TiO2 nanostructures and the surface hydrophilicity induced by titanium oxy-fluoride groups, the as-prepared Ti foam exhibited superhydrophilicity and underwater superoleophobicity. The formation of flower-like TiO2 nanostructures was studied and a possible “partial replacement” fluorinated process was proposed. Oil in water emulsion separation test showed that the superhydrophilic Ti foam could handle with various emulsions only under gravity with high separation efficiency over 99%. The separation efficiency remained high even after 20 times of reusing, demonstrating good reusability. More importantly, the superhydrophilic Ti foam could still maintain its wettability after immersed corrosive solutions for 48 h or stored under ambient atmosphere for three months, indicating excellent anti-corrosion property and long-term storage stability. We envision the methodology for the construction of a superhydrophilic surface by a simple and low-cost hydrothermal process will shed light on the Ti-based material design and also pave the way for applications in other fields such as liquid manipulation, fluidic devices and bioadhesion control.

Extraordinary high strength Ti-Zr-Ta alloys through nanoscaled, dual-cubic spinodal reinforcement.

The current research details microstructural, mechanical, and biological investigations into four novel biomedical alloys in a hitherto uninvestigated region of the Ti-Zr-Ta alloy system; Ti-45Zr-10Ta, Ti-40Zr-14Ta, Ti-35Zr-18Ta and Ti-30Zr-22Ta. We find that the investigated alloys display 0.2% yield strengths of up to 1.40GPa and elastic admissible strains of up to 1.48%, along with biological properties comparable to that seen in the conventional metallic biomaterial ASTM Grade-2 CP-Ti, achieved in the complete absence of traditional thermomechanical processing techniques. This is attributed to the presence of a dual-BCC cuboidal nanostructure, achieved via spinodal decomposition; while similar structures have been reported in e.g. Ni-based superalloys, we believe this is the first such structure investigated in a Ti-based material. As such, this work is felt to be of great interest in aiding the design and manufacture of highly-biocompatible, porous, metallic biomaterials for orthopedic application.

Photocatalytic Degradation of Methylene Blue by the La-N/TiO&lt;sub&gt;2&lt;/sub&gt; Composite and its Kinetic Enumeration

Photocatalytic degradation kinetics of methylene blue in aqueous solution was systematically investigated using Ti-based composite material as the photocatalyst. The single-variable-at-a-time ( SVAT) method was employed. It studied the individual and synergistic effects of several classical parameters on photocatalytic efficiencies. The kinetic mechanism was systematically explored. The kinetics effects of the doping amount of La and N, calcination temperature and time, light intensity were studied in detail. The factors on the degradation of MB were in accordance with the pseudo first order kinetic model. This kinetic model followed the Langmuir–Hinshelwood model. The best preparation conditions were found in the experiments. It is proved that the Ti-based composite material is an effective adsorbent for the degradation of dye contaminated water.

Synthesis, Characterization and Photocatalytic Activity of La&lt;sub&gt;2&lt;/sub&gt;O&lt;sub&gt;3&lt;/sub&gt;-N/TiO&lt;sub&gt;2&lt;/sub&gt; for Methylene Blue Removal under UV Irradiation

In this work, the novel Ti-based composite material has been synthesized, characterized and studied for the photocatalytic degradation of methylene blue(MB). The effects of the doping amount of La and N, calcination temperature and time, light intensity were studied in detail. The strong synergism of La, N and TiO2 was discussed during the photocatalytic process. The results suggested that the degradation efficiency was obviously improved by the Ti-based photocatalyst and the La element could enhance the photocatalytic degradation performance significantly, and the best molar ratio of N and TiO2 was 0.000014:1. The study found that the best preparation conditions can also improve the photocatalytic activity, the optimal material was made after calcining for 4h at 800°C. What is more, the higher illumination power was benifit for the degradation of the MB. It is indicated that the mixed crystal Ti-based composite material being an effective adsorbent for the elimination of the contaminated water by dyes. In addition, the work provide new direction for future research.

Li2TiSiO5: a low potential and large capacity Ti-based anode material for Li-ion batteries

Li2TiSiO4with a 0.28 V operational potential may fill the gap between the present 0.1 V carbonaceous and the 1.5 V Li4Ti5O12electrodes.