Sodium Titanate Research Articles

Sodium titanate (Na2Ti4O9) nanoribbons for effective removal of organic dyes from water: Experimental and computational studies

Sodium titanate (Na2Ti4O9) nanoribbons for effective removal of organic dyes from water: Experimental and computational studies

0D/1D p-n heterostructured composite of bismuth ferrite perovskite clusters on sodium titanate nanotube arouse exceptional blue-light-driven photooxidation

This study describes the synthesis of a 0D/1D p-n heterostructured composite of bismuth ferrite perovskite clusters on sodium titanate nanotubes prepared using an in-situ hydrothermal method. BiFeO3/Na2Ti3O7 (BFT) nanocomposite, forming a p-n heterojunction due to the equilibrium of Fermi level, exhibits exceptional blue-light-driven photo-oxidation activity with an exceptional benzyl alcohol conversion rate of 29.64 mmolproduced BAD·g−1 h−1. The outstanding performance originates from the promotion of photogenerated charge separation and effective inhibition of charge recombination due to internal electric field of p-n heterojunction. Density functional theory calculations combined with femtosecond transient absorption spectroscopy distinctly confirms the efficient separation and transfer of photogenerated carriers to be S-scheme charge transfer mechanism over the p-n heterojunctions. Furthermore, in-situ infrared spectroscopy combined with XPS results demonstrate the strong adsorption of benzyl alcohol and weak adsorption of benzaldehyde on BFT, which facilitates the transformation of reactant and desorption of product. This study provides a simple and effective approach to enhance photocatalytic selective oxidation reactions.

Monolayer Sodium Titanate Nanobelts as a Highly Efficient Anode Material for Sodium‐Ion Batteries

Monolayer Sodium Titanate Nanobelts as a Highly Efficient Anode Material for Sodium‐Ion Batteries

From mixed brookite/anatase TiO2 nanopowder to sodium titanates: Insight into morphology, structure, and photocatalytic performance

A method to obtain sodium titanate nanoribbons starting from a mixture of brookite and anatase TiO₂ nanopowder is described. As-prepared TiO2 nanopowder with a major brookite phase was used as a precursor in an alkaline hydrothermal approach, where the temperature was kept at 200 °C. The influence of hydrothermal treatment and consequent annealing temperature (T = 500 °C) on the crystal structure, phase composition, and morphology of samples were investigated by X-ray powder diffraction (XRPD), Raman and FTIR spectroscopy, and electron microscopy techniques (FESEM, HRTEM). All these methods point out that the hydrothermally treated sample, containing the NaTi3O6(OH)(H2O)2, Na2Ti3O7, and Na2Ti9O19, is dominated by layer-structured sodium hydroxititanate dihydrate. The annealing leads to the formation of rare sodium titanates, Na3Ti6O13 and Na2Ti9O19, with tunnel structures where the hexatitanate with increased sodium content prevails. The photocatalytic activity of synthesized nanostructures was tested in the degradation process of Reactive Orange (RO16) azo-dye upon UV excitation. It appears that photocatalytic activity is lower after hydrothermal treatment, but subsequent annealing makes sodium titanate nanoribbons faster in the degradation of RO16. The research implies that these sodium titanate nanostructures are promising photocatalytic materials and should be considered in the future for removing different pollutants from water.

Benchmarking the Performance of Lithium and Sodium‐Ion Batteries With Different Electrode and Electrolyte Materials

ABSTRACTSodium‐ion (Na‐ion) batteries are considered a promising alternative to lithium‐ion (Li‐ion) batteries due to the abundant availability of sodium, which helps mitigate supply chain risks associated with Li‐ion batteries. Many studies have focused on the design of Li‐ion batteries, exploring their energy, power, and cost aspects. However, there is still a lack of similar research conducted on Na‐ion batteries. A comparison of the cell voltage characteristics and rate capability of sodium and lithium‐ion batteries using different types of electrodes and electrolytes. For sodium‐ion batteries electrolytes used are NaPF6 and NaClO4 and electrodes used are NaCoO2, NaNiO2, NaFePO4, (Na3V2(PO4)3), graphite, hard carbon, sodium metal, and sodium titanate. For lithium‐ion batteries with LiPF6 and KOH electrolytes and electrodes as LiCoO2, NMC, LVP, Li2MnSiO4, graphite, silicon, lithium titanate (LTO), lithium metal. A thorough analysis of six important performance metrics is part of the investigation: Ragone plots, Electrolyte salt concentration versus spatial coordinate, electrolyte potential versus spatial coordinate, Cell voltage versus battery cell state of charge, Cell voltage versus time, and state variable versus time. Comparing operating voltage and rated capacity NMC and graphite is selected for lithium‐ion batteries as this combination provides operating voltage up to 4.2 V and a rated capacity of 275 Wh/kg, for sodium‐ion for NaCoO2 and hard carbon which has an operating voltage of 2.5–3.8 V and rated capacity around 200 Wh/kg and another combination of electrode as NaFePO4 and sodium metal with NaClO4 electrolyte has a maximum operating voltage of 2.8–3.8 V and rated capacity around 200 Wh/kg. This paper shows significant influence of electrolyte selection on battery performance. The Ragone plots demonstrate that LiPF6 electrolytes in lithium‐ion batteries and NaPF6 electrolytes in sodium‐ion batteries both exhibit superior specific energy densities compared to their KOH and NaClO4 counterparts, respectively. The work presented in this paper encourages researchers to select alternate electrolytes and electrodes for lithium‐ion and sodium‐ion batteries in order to obtain optimal device performance.

Sol-gel synthesized flexible Na2Ti6O13–aluminium oxide fibres for photocatalytic degradation of Acid red 1

Sodium titanate (Na2Ti6O13; NTO) was loaded onto aluminium oxide fibres (AFs) using the sol–gel method to synthesize NTO/AF fibres. The surface roughness of NTO/AF-n fibres increased with increasing number of dip-coating cycles (n = 1–3). The Fourier transform infrared spectra and X-ray photoelectron spectroscopy spectra of NTO/AF-n demonstrated the loading of NTO onto AF. The bandgap energies of NTO/AF-1, NTO/AF-2, NTO/AF-3 and NTO were determined to be 3.08, 3.12, 3.38 and 3.45 eV, respectively. The production of hydroxyl radicals by fibres under irradiation decreased in the order of NTO, NTO/AF-1, NTO/AF-2 and NTO/AF-3. NTO/AF-n fibres were designed for convenient separation from water, with NTO/AF-1 exhibiting the highest activity among the NTO/AF-n samples. The photocatalytic degradation efficiencies of NTO/AF-1, NTO/AF-2 and NTO/AF-3 after 30 min of reaction were determined to be 61.4 %, 51.7 % and 44.3 %, respectively. Complete removal of Acid Red 1 from the solution was achieved through a photocatalytic reaction using NTO/AF-n. The activity of NTO/AF-n samples remained stable over five reaction cycles, indicating their application potential for large-scale water treatment.

Photocatalytic Nanocomposite Based on Titanate Nanotubes Decorated with Plasmonic Nanoparticles for Enhanced Broad-Spectrum Antibacterial Activity.

Infections resulting from microorganisms pose an ongoing global public health challenge, necessitating the constant development of novel antimicrobial approaches. Utilizing photocatalytic materials to generate reactive oxygen species (ROS) presents an appealing strategy for combating microbial threats. In alignment with this perspective, sodium titanate nanotubes were prepared by scalable hydrothermal method using TiO2 and NaOH. Ag, Au, and Ag/Au-modified titanate nanotubes (TNTs) were prepared by a cost-effective and simple ion-exchange method. All samples were characterized by XRD, FT-IR, HRTEM, and DLS techniques. HRTEM images indicated that the tubular structure was preserved in all TNTs even after the replacement of Na+ with Ag+ and/or Au3+ ions. The antibacterial activity in dark and sunlight conditions was evaluated using different bacterial strains, Staphylococcus aureus, Escherichia coli, and Pseudomonas aeruginosa. The results showed that while a low bacterial count (∼log 5 cells per well) was used for inoculation, the TNTs exhibited no antibacterial activity against the three bacterial strains, regardless of whether they were tested under light or dark conditions. However, the plasmonic nanoparticle-decorated TNTs showed remarkable activity in the dark. Additionally, Ag/Au-TNTs demonstrated significantly higher activity in the dark compared with either Ag-TNTs or Au-TNTs alone. Notably, under dark conditions, the Au/Ag-TNTs achieved log reductions of up to 4.5 for P. aeruginosa, 5 for S. aureus, and 3.7 for E. coli. However, when exposed to sunlight, Au/Ag-TNTs resulted in a complete reduction (log reduction ∼9) for P. aeruginosa and E. coli. The combination of two plasmonic nanoparticles (Ag/Au) decorated on the surface of TNTs showed synergetic bactericidal activity under both dark and light conditions. Ag/Au-TNTs could be explored to design surfaces that are responsive to visible light and exhibit antimicrobial properties.

Microwave-Assisted Fabrication and Characterization of Carbon Fiber-Sodium Bismuth Titanate Composites

Lead-based piezoelectric materials cause many environmental problems, regardless of their exceptional performance. To overcome this issue, a lead-free piezoelectric composite material was developed by incorporating different percentages of carbon fiber (CF) into the ceramic matrix of Bismuth Sodium Titanate (BNT) by employing the microwave sintering technique. The aim of this study was also to evaluate the impact of microwave sintering on the microstructure and the electrical behavior of the carbon-fiber-reinforced Bi0.5Na0.5TiO3 composite (BNT-CF). A uniform distribution of the CF and increased densification of the BNT-CF was achieved, leading to improved piezoelectric properties. X-ray diffraction (XRD) showed the formation of a phase-pure crystalline perovskite structure consisting of CF and BNT. A Field Emission Scanning electron microscope (FESEM) revealed that utilizing microwave sintering at lower temperatures and shorter dwell times results in a superior densification of the BNT-CF. Raman Spectroscopy confirmed the perovskite structure of the BNT-CF and the presence of a Morphotropic Phase Boundary (MPB). An analysis of nanohardness indicated that the hardness of the BNT-CF increases with the increasing amount of CF. It is also revealed that the electrical conductivity of the BNT-CF at a low frequency is significantly influenced by the amount of CF and the temperature. Moreover, an increase in the carbon fiber concentration resulted in a decrease in dielectric properties. Finally, a lead-free piezoelectric BNT-CF showing dense and uniform microstructure was developed by the microwave sintering process. The promising properties of the BNT-CF make it attractive for many industrial applications.

PVA/titanate nanotube nanocomposites: Evaluating the required structural properties for their performance as macromolecule delivery systems

AbstractBiopolymer‐based nanocomposites are gaining prominence in the fabrication of biomedical devices, with polyvinyl alcohol (PVA) being widely used in smart dressings for drug and protein integration. This study introduces electrospun mats composed of partially hydrolyzed PVA and sodium titanate nanotubes (TiNTs). The investigation involved mats with TiNT concentrations ranging from 0% to 5% at room temperature. The morphological and structural changes resulting from adding TiNTs were examined in detail. The inclusion of TiNTs impacted parameters such as mean fiber diameter (130–190 nm), crystallinity degree (30–50%), and porosity (70–55%) and was closely associated with the viscoelastic properties of the mats. Higher TiNT concentrations led to reductions in either the storage modulus, from 350 to 220 MPa, or in the loss modulus, from 30 to 25 MPa, unveiling an increase in tenacity. Furthermore, in vitro release tests were conducted using bovine serum albumin (BSA) in Franz cells over 48 h. The results indicated that release profiles were best fitted by the Higuchi model (0.95 > R2 > 0.99) for both PVA mats (0% and 5.0% TiNTs), with the 5% TiNTs‐PVA membrane demonstrating greater BSA diffusion when compared to pure PVA. The release constant 𝐾rel, representing the rate of drug diffusion, was found to be 0.006 for 5% TiNT‐PVA mats and 0.002 μg h‐1/2 for pure PVA, respectively. These results suggest the potential of these materials in designing controlled transdermal delivery systems that could significantly improve the efficacy and safety of drug applications.

Design of Na2Ti3O7/Na2Ti6O13 nanorods for sodium-ion batteries from titanium oxysulfate solution

Sodium titanate is currently a widely studied anode electrode material for sodium-ion batteries, showing promising potential for large-scale production and applications. Current research focuses on Na2Ti3O7, Na2Ti6O13, and their mixed compositions Na2Ti3O7/Na2Ti6O13, utilizing high-purity titanium compounds as raw materials. In this study, precursors of biased titanate with three different sulfur contents (3.20 %, 2.04 %, 0.28 %) are prepared using a self-seeding hydrolysis method and a titanium oxysulfate (TiOSO4) solution as the starting material. During the synthesis of sodium titanate, sodium consumption occurs due to sulfur, resulting in a mixed phase comprising Na2Ti3O7/Na2Ti6O13. However, when the sulfur content is very low, a single phase of Na2Ti3O7 can be obtained. Notably, Na2Ti3O7/Na2Ti6O13 synthesized from biased titanate with high sulfur content exhibits a larger percent of Na2Ti6O13, which improves rate capability and cycling stability. The initial discharge specific capacity at 177 mA·g−1 is 57.4 mAh·g−1, and after 1000 cycles, the discharge capacity reaches 22.7 mAh·g−1. Designing mixed materials Na2Ti3O7/Na2Ti6O13 from TiOSO4 solution represents one of the pathways to achieve high-performance sodium titanate materials.

KNN composite ceramics with superior pyroelectric performance for self-powered thermal detector

The thermal detector based on pyroelectric effect has attracted widespread attention due to its self-powering and rapid response. Although phase boundary engineered lead-free potassium sodium niobate [K0.5Na0.5NbO3, KNN] based ferroelectrics exhibit promising for pyroelectric sensor application, the high dielectric constants (εr) of these materials significantly constrain their pyroelectric figures of merit (FOMs), owing to the inverse correlation between FOMs and εr. To address this problem, we innovatively introduce perovskite bismuth sodium titanate [Bi0.5Na0.5TiO3, BNT] with low εr and high pyroelectric coefficient as the second phase to construct a KNN/BNT composite. The introduction of BNT can not only remain the high pyroelectric coefficient (p=7.12 × 10−4 C m−2 K−1) of KNN matrix, but also result in superior FOMs (Fv increased by 74 %), outperforming previous KNN-based pyroelectric ceramics. The excellent pyroelectric performance originates from the unique composite microstructure with compositional heterogeneity. That is, both the low εr BNT enriched phase and refined grain size as well as the promoted vibration of Nb–O octahedron contribute to the superior pyroelectric performance. A self-powered thermal detector with great thermal response has been developed, which also exhibits potential for detecting ultraviolet energy and infrared radiation.

Enhancing Energy Storage Performance of 0.85Bi0.5Na0.5TiO3-0.15LaFeO3 Lead-Free Ferroelectric Ceramics via Buried Sintering.

Bismuth sodium titanate (Bi0.5Na0.5TiO3, BNT) ceramics are expected to replace traditional lead-based materials because of their excellent ferroelectric and piezoelectric characteristics, and they are widely used in the industrial, military, and medical fields. However, BNT ceramics have a low breakdown field strength, which leads to unsatisfactory energy storage performance. In this work, 0.85Bi0.5Na0.5TiO3-0.15LaFeO3 ceramics are prepared by the traditional high-temperature solid-phase reaction method, and their energy storage performance is greatly enhanced by improving the process of buried sintering. The results show that the buried sintering method can inhibit the formation of oxygen vacancy, reduce the volatilization of Bi2O3, and greatly improve the breakdown field strength of the ceramics so that the energy storage performance can be significantly enhanced. The breakdown field strength increases from 210 kV/cm to 310 kV/cm, and the energy storage density increases from 1.759 J/cm3 to 4.923 J/cm3. In addition, the energy storage density and energy storage efficiency of these ceramics have good frequency stability and temperature stability. In this study, the excellent energy storage performance of the ceramics prepared by the buried sintering method provides an effective idea for the design of lead-free ferroelectric ceramics with high energy storage performance and greatly expands its application field.

Stoichiometric Study on Ion Composition of a Precursor in Chemical Bottom-Up Synthesis for Peroxo-Titanate.

Layered alkali titanates of the lepidocrocite type are gaining enormous interest in various fields owing to their unique properties. These materials are mainly synthesized through a hydrothermal alkali treatment. However, this method uses a highly concentrated alkali solution, which has high environmental impacts and is therefore unsuitable for mass synthesis. Herein, we propose an efficient method for the large-scale synthesis of layered sodium titanate structures (Na2-x H x Ti2O5) using a recently reported bottom-up chemical process. The effects of the Na:Ti molar ratio in the peroxo-titanium complex ion precursor on the products are investigated through stoichiometric calculations for a molar ratio range of 10:1-1:1. The optimal ratio for the complete ionization of TiH2 (which is the starting material) to form the peroxo-titanium complex ion is found to be 1.1:1. The amount of alkali raw material required is 99.6% lower than that required in the traditional hydrothermal method. The crystal structures and morphologies of the samples are almost identical regardless of the Na:Ti molar ratio. The precursor-derived peroxo bonds narrow the energy band gaps of the layered titanates even when the amount of titanium ions dissolved in the precursor increases. The proposed method is not only an efficient synthetic route for mass production but also has potential applications in the development of photofunctional materials.

Effects of Cation Exchange in Rhodamine B Photocatalytic Degradation Using Peroxo-Titanate Nanotubes.

Lepidocrocite-type layered sodium titanate (NaxH2-xTi2O5) is widely used in environmental remediation because of its large specific surface area, formed by anisotropic crystal growth, and its ability to store and exchange cations between layers. Additionally, peroxo-titanate nanotubes (PTNTs), which are tubular titanates with peroxy groups, exhibit visible-light absorption capabilities, rendering them suitable for photocatalytic applications under visible light irradiation. However, because of cation exchange reactions, the Na+ concentration and pH of the solution can fluctuate under aqueous conditions, affecting the photocatalytic performance of the PTNTs. Herein, we evaluated the impact of cation exchange reactions on the photocatalytic degradation of Rhodamine B (Rh B) by PTNTs at controlled Na+ ratios. The observed pH of Rh B solutions increases due to the cation exchange reaction with Na+ and H3O+, leading to the formation of zwitter-ionic Rh B molecules, eventually weakening their adsorption and photodegradation performance. Moreover, the results indicate that inhibiting the pH increase of the Rh B solution can prevent the weakening of both the adsorption and photodegradation performance of PTNTs. This study highlights the significance of regulating the sodium ion content in layered titanate materials, emphasizing their importance in optimizing these materials' photocatalytic efficacy for environmental purification applications.

Sodium titanate nanostructured modified by green synthesis of iron oxide for highly efficient photodegradation of dye contaminants

Abstract In this study, sodium titanate (ST)/iron oxide (Fe2O3) was successfully prepared as a novel binary photocatalyst for the first time to enhance the photocatalytic activity. The prepared photocatalyst was used in the photodegradation of methylene blue (MB) dye under sunlight and a tungsten lamp. The green synthesis method using orange peel extract was employed to prepare Fe2O3, while the hydrothermal method was used to synthesize ST. To achieve optimal photocatalytic efficiency, the loading of Fe2O3 onto ST was carefully controlled. The average crystallite size of ST, Fe2O3, and ST@Fe2O3 (with a 1:1 wt% ratio) was 999.8, 81.9, and 104 nm, respectively, using the Williamson–Hall (W–H) model. Optical analysis revealed that ST@Fe2O3 had a smaller direct bandgap (2.54 eV) compared to ST@0.3 Fe2O3 (2.70 eV) and ST@0.5 Fe2O3 (3.24 eV). The photodegradation of MB was analyzed considering the weight of the photocatalyst, the irradiation time, and the dye concentration. In-depth explanations of stability and kinetic models were also provided. Remarkably, the ST@Fe2O3 photocatalyst demonstrated superior performance compared to the other evaluated photocatalysts, completely degrading MB dye within just 60 min of solar light exposure. Incorporating Fe2O3 into ST effectively reduces the recombination of photo-produced electron/hole (e/h) pairs and broadens the response range of the solar spectrum. Based on these findings, ST@Fe2O3 appears to have a promising future as a practical photocatalyst for degrading various dye pollutants in wastewater.

Ultra-large strain response in BNT-BT-KNN thin films boosted by electric field-induced inversion of long-range ordered polarization

Bismuth sodium titanate (BNT)-based piezoelectric materials are the most promising candidates for lead-free actuator applications. With the request for integration and size miniaturization of devices, it is urgent to develop thin films for microdevices to be compatible with semiconductor processes. Through composition engineering, BNT-based thin films were fabricated on silicon substrates, with ultra-high strain response and negligible hysteresis in strain curves. The DC-dependent and temperature-dependent dielectric properties were collected to investigate the relaxor state of thin films. The structure and polarization transition and evolution as a function of electric field and time were analyzed based on the electric characterization, in-situ Raman measurements, and dynamics PFM. The reversible phase transition and polarization order-disorder transformation are the most significant features for reaching a large strain of >1.6% in BNT-based thin films.

Magnetic sodium titanate nanotubes for simultaneous recovery of multiple low-level heavy and radioactive metal ions

Heavy and radioactive metal ions pollutants in water are a serious environmental problem and cause various health issues which lead to fetal human diseases. Herein, magnetic sodium titanate nanotubes (Fe3O4/NaTNTs) as magnetically separable nanostructure composite material were synthesized and used as adsorbent for simultaneous removal of multiple metal ions contaminants. HRTEM, SEM, FTIR, EDX, XRF, XRD, thermal gravimetric analysis (TGA), and zeta potential analysis were used for Fe3O4/NaTNT characterization. Thirteen metal cations including Th4+ and U4+, have been tested for competitive and simultaneous sorption on Fe3O4/NaTNTs nanostructure. In the mixed metal ions system, the removal efficiency of Co2+ and Pb2+ is the highest (Co2+; 95.9 %, Pb2+; 94.2 %). The relative selectivity for the removal of Cs+ ions (32 %) is more than that of Sr2+ ions (25 %). Thus, the data indicates the potential of Fe3O4/NaTNTs to be used in wastewater treatment, especially to simultaneously remove multiple heavy metal ions. Fe3O4/NaTNTs sorbent can be used for the rapid removal of heavy elements to mitigate large quantities of water pollution in emergencies, such as nuclear accidents and leaks.

Enhanced comprehensive energy storage properties in Bi0.5Na0.5TiO3-based relaxor ferroelectric ceramics under a moderate electric field

Bismuth sodium titanate (Bi0.5Na0.5TiO3)-based relaxor ferroelectric ceramics have received ever-increasing interest for their potential application in dielectric capacitors owing to their sterling energy storage capability. Herein, the perovskite end-member Ba(Fe0.5Nb0.5)O3 (BFN) was incorporated into 0.7Bi0.5Na0.5TiO3-0.3SrTiO3 (0.7BNT-0.3ST) ceramics to improve the relaxor characteristics and refine the grain, leading to slim polarization–electric field (P–E) hysteresis loops and enhanced electric breakdown strength. Particularly, the 0.85(0.7BNT-0.3ST)-0.15BFN ceramics achieved a high recoverable energy density of 5.7 J/cm3 and a high energy storage efficiency of 86.4% under a moderate electric field of 390 kV/cm. Additionally, remarkable stability in frequency, cycling, and temperature and excellent charge/discharge behavior were achieved at the same time. The above findings reveal that BFN-modified BNT-ST ceramics display greatly improved comprehensive energy storage properties, making them promising candidates in the field of electrostatic energy storage.

Improvement of thermomechanical and dielectric properties of thermoplastic polyurethane using bismuth sodium titanate/carbon nanotube hybrid fillers

AbstractThe development of innovative composite materials through the amalgamation of thermoplastic polyurethane (TPU) with bismuth sodium titanate (BNT) and carbon nanotube (CNT) fillers was investigated. Before the composite fabrication, the fillers' surfaces were treated to enhance their compatibility with the TPU matrix. Hybrid fillers of BNT and CNTs were fabricated by mixing the two types of filler particles through ball milling and subsequently annealing the mixture at 250°C. Melt‐blending and injection molding were utilized to synthesize the composites at 210°C processing temperature. The prepared composites showed significantly enhanced thermal conductivity, dielectric constant, thermal stability, and thermomechanical properties compared with the neat TPU matrix. For instance, the dielectric constant was enhanced by 340% upon the inclusion of 40 wt.% BNT and CNT fillers compared to the neat TPU matrix (40CBNT‐TPU has 13.2). In particular, the inclusion of BNT‐CNT particles in the TPU matrix improved the thermal conductivity of the TPU matrix by 1180% tremendously as compared to neat TPU (40CBNT‐TPU has 2.6 W/(m.K)).Highlights Crystalline bismuth sodium titanate (BNT) is fabricated. Degradation of 8 wt.% of the IPDI‐treated BNT proves surface treatment. Dielectric constant (DC) improved by 340% compared to neat TPU. Thermal conductivity (TC) enhanced 11.4 times compared to neat TPU. Improvement in TC and DC will make it applicable in electronic materials.

Preparation and Characterization of Nanofiber Coatings on Bone Implants for Localized Antimicrobial Activity Based on Sustained Ion Release and Shape-Preserving Design.

Titanium (Ti), as a hard tissue implant, is facing a big challenge for rapid and stable osseointegration owing to its intrinsic bio-inertness. Meanwile, surface-related infection is also a serious threat. In this study, large-scale quasi-vertically aligned sodium titanate nanowire (SNW) arrayed coatings incorporated with bioactive Cu2+ ions were fabricated through a compound process involving acid etching, hydrothermal treatment (HT), and ion exchange (IE). A novel coating based on sustained ion release and a shape-preserving design is successfully obtained. Cu2+ substituted Na+ in sodium titanate lattice to generate Cu-doped SNW (CNW), which maintains the micro-structure and phase components of the original SNW, and can be efficiently released from the structure by immersing them in physiological saline (PS) solutions, ensuring superior long-term structural stability. The synergistic effects of the acid etching, bidirectional cogrowth, and solution-strengthening mechanisms endow the coating with higher bonding strengths. In vitro antibacterial tests demonstrated that the CNW coatings exhibited effective good antibacterial properties against both Gram-positive and Gram-negative bacteria based on the continuous slow release of copper ions. This is an exciting attempt to achieve topographic, hydrophilic, and antibacterial activation of metal implants, demonstrating a paradigm for the activation of coatings without dissolution and providing new insights into insoluble ceramic-coated implants with high bonding strengths.