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The current study was conducted by introducing a narrow bandgap semiconductor, ZnIn 2 S 4 , with the goal of addressing the inefficiency of hydrolysis dissociation and the limited visible light absorption capacity faced by TiO 2 as a hydrogen evolution reaction (HER) catalyst due to its low conduction band position and wide bandgap. Using a one-step hydrothermal process, ZnIn 2 S 4 nanosheet/TiO 2 nanorod heterostructures were built on nickel foam substrates. The nanosheet structure of ZnIn 2 S 4 is shaped like a flower, which greatly increased the roughness of the TiO 2 surface and revealed additional active sites. The ZnIn 2 S 4 /TiO 2 heterostructure demonstrates quick reaction kinetics and effective electron transport capability, as demonstrated by the electrochemical test results. An overpotential of just 195 mV is required to obtain a current density of 10 mA cm−2. In addition, the overpotential is further decreased to 160 mV under simulated solar radiation. Furthermore, ZnIn 2 S 4 addition minimizes the free energy of hydrogen adsorption on the TiO 2 surface and optimizes the position of its Fermi energy level, improving the usage of photogenerated carriers, according to density functional theory (DFT) calculations. This work validates the prospective use of ZnIn 2 S 4 /TiO 2 heterostructures in photoelectrocatalysis and offers a fresh viewpoint for developing high-performance HER catalysts. • Composite of TiO 2 with ZnIn 2 S 4 exposes more active sites and improves HER performance. • Changes in d-band center and free energy explain catalytic performance enhancement. • Formation of interfacial electric field improves HER performance of TiO 2. [ABSTRACT FROM AUTHOR]

Hydrogen production by photocatalysis water splitting is an attractive and promising development method, but the current efficiency is too low for application. Loading single atoms can significantly enhance the photocatalytic efficiency, however, the insightful understanding of the impact of single atom loading on catalytic performance is still ambiguous. In this work, In SA /TiO 2 photocatalysts modified with indium single atom (In SA) were synthesized by photo-deposition process. Under 300W Xe lamp illumination, the hydrogen production rate of the optimized In SA /TiO 2 photocatalyst achieves 6.11 mmol g−1 h−1, which is 7.6 times that of TiO 2 prepared under the same conditions. The results of characterization analysis and density functional theory (DFT) calculations indicate that some of the Ti atoms on the TiO 2 surface are replaced by the doped In, and the local electronic structures of the photocatalyst are regulated, which results in effectively separating of the photo-generated carriers, and significant increasing the activity of the surrounding unsaturated oxygen, thus, the photocatalytic hydrogen production performance is effectively improved. This work provides a strategy to improve photocatalytic activity, and also deepens the understanding of metal single atom modification mechanism. • In SA significant increasing the activity of the surrounding O Vs. • The surface local electronic structures of TiO 2 are regulated by loading In SA. • H 2 evolution rate of In SA /TiO 2 is 7.6 times that of TiO 2 under 300W Xe illumination. [ABSTRACT FROM AUTHOR]

The Ag + ions doped TiO 2 nanotube arrays fabricated on Ti mesh through an electrochemical anodization process, and n/n heterostructure formed by coating the TiO 2 nanotube array photoanode with an n-type stibnite (Sb 2 S 3) layer improve photoelectrochemical water splitting reaction by enhancing light harvesting and charge carrier separation. Sb 2 S 3 is chosen because of its suitable band gap position and strong visible light response. The Ag + ion incorporated TiO 2 nanotube array coated with Sb 2 S 3 exhibits a photocurrent density of 6.5 mA cm−2 vs. RHE, whereas bare TiO 2 nanotube array coated with Sb 2 S 3 and pristine TiO 2 nanotube array exhibit photocurrent densities of 3.6 and 0.27 mA cm−2, respectively, under the same conditions, which is nearly 1.8 and 24 times greater than the TiO 2 nanotube array coated with Sb 2 S 3 and pristine TiO 2 nanotube array photoanodes. The applied bias photon-to-current efficiency of Ag + ion incorporated TiO 2 nanotube array coated with Sb 2 S 3 is 3.6% and the improved Photoelectrochemical performance of Ag + ion doped TiO 2 nanotube array coated with Sb 2 S 3 is attributable to higher conductivity of TiO 2 nanotube array caused by increased oxygen vacancies and broad optical activity of Sb 2 S 3. The 1-dimensional TiO 2 nanotube array device structure in the Ti mesh improves charge separation and light harvesting while reducing photogenerated charge carrier recombination and the potential of this novel device structure for advanced energy conversion applications is highlighted in this study. [Display omitted] • Ag + ions doped TiO 2 nanotube array-Sb 2 S 3 Schottky-junction was fabricated on a porous titanium substrate. • The TiO 2 –Sb 2 S 3 device was tested for photoelectrochemical water splitting reaction. • Ag + doped TiO 2 –Sb 2 S 3 Schottky junction enhances light harvesting and charge carrier separation. • The potential of the novel PEC device for water splitting is highlighted. [ABSTRACT FROM AUTHOR]

Nanotechnology: is the art and science of dealing with nanoscale particles. This has transformed contemporary dental practices through myriad contributions to biomaterial science. Titanium dioxide nanoparticles procured from Bacillus subtilis, an eco-friendly and biogenic source, can significantly magnify the physiochemical attributes of dental materials. However, postoperative sensitivity is a major drawback of composite restorations. The incorporation of these nanoparticles into dental adhesives can greatly benefit clinical dentistry by resolving this issue. This trial aimed to evaluate the effectiveness of a novel titanium dioxide nanofortified adhesive on the postoperative sensitivity of composite restorations. Methods: This triple-blind, parallel-group randomized controlled trial was conducted at the Department of Operative Dentistry and Endodontics, School of Dentistry, Islamabad, from May 15, 2023, to November 25, 2023. Participants (n = 60) with Class I and II primary carious lesions with a minimum cavity depth of 3–5 mm were randomly assigned to two groups (n = 30). After obtaining informed consent, the restorative procedure was accomplished using a minimally invasive approach and etch-and-rinse adhesive strategy. In group A, a nanofortified adhesive was used for composite restoration, whereas in group B, an adhesive without nanoparticles was used. Postoperative sensitivity was evaluated using the Visual Analog Scale (VAS) score at follow-up periods: of one day, one week, two weeks and one month. A Chi-square test was used to compare postoperative sensitivity between the two groups. The level of significance was set at p < 0.05. Results: A noteworthy association was observed between sensitivity and the group variable at all four evaluation periods: after one day (p = 0.002), 1 week (p = 0.002), 2 weeks (p = 0.007) and one month. In conclusion, participants who underwent restorative intervention using titanium dioxide nanoreinforced adhesives reported a notable reduction in sensitivity at all time intervals. Hence, the occurrence and severity of postoperative sensitivity are significantly reduced using Bacillus subtilis-procured nanofortified adhesives as compared to conventional adhesives without nanoparticles. Trial registration: This trial was retrospectively registered at ClinicalTrials.gov (ID: NCT06242184) on 03/02/2024. All procedures involving human participants were performed in conformance with this protocol. [ABSTRACT FROM AUTHOR]

In this work, the photo-, electro-, and photo-electro-oxidation of chloramphenicol was investigated. The photo-experiments were carried out with different irradiation sources (an ultraviolet and a simulated solar source) using self-doped titanium nanotubes (SDTNT), a very promising and innovative material that deserves further investigations in the degradation of different pollutants. The photo-electrooxidation (j = 15 mA cm–2) under simulated solar irradiation presented the best efficiency, with ca. 100% degradation and kinetic constant of k = 0.04427 min–1. The FTIR analysis demonstrated a structural modification of the standard molecule occurred for all conditions used, suggesting a modification in functional groups responsible for the biological activity. Furthermore, the TOC analysis showed a significant mineralization of the pollutant (66% from the initial concentration). In addition, both photo-electrooxidation approaches have demonstrated a positive value of S, where the simulated solar irradiation reached the highest value S = 0.6960. The experimental results pointed out evidence that the methodology employed herein for chloramphenicol degradation is greatly interesting and the photo-electrooxidation under simulated solar irradiation is a promising approach for this purpose. [ABSTRACT FROM AUTHOR]

To make pyrolytic bio‐oil useful as a transportation fuel, the oxygen content must be reduced, and this can be carried out by using catalytic hydrodeoxygenation (HDO) reaction. The greatest challenge is associated with the removal of strongly bound oxygenated groups without saturating the aromatic ring while preserving the number of carbons. However, the development of a stable catalyst that can selectively remove such oxygenated groups with low hydrogen consumption is still challenging. In this context, a systematic study on HDO of vanillin on bimetallic Pd−Pt catalysts was carried out. It aims to study the effect of bimetallic synergy in terms of activity and selectivity to creosol. Metallic nanoparticles of Pd and Pt were synthesized by sol immobilization technique and deposited on TiO2. The conversion of vanillin was correlated to the Pd−Pt atomic ratio, while the production of the creosol was correlated to the Pd(0)/(Pd+Pt) ratio at the surface. Full conversion of vanillin was obtained at low reaction temperature (20 °C) achieving nearly 100 % selectivity to creosol. These results represent a step forward in advancing the development of more efficient and sustainable processes for bio‐oil upgrading. [ABSTRACT FROM AUTHOR]

Highlights For preparing high performance LLDPE film, the photocatalytic activity and the UV absorption capacity of TiO2 were regulated by the alumina coating content on the surface of TiO2. Alumina‐coated TiO2 was prepared by the chemical liquid deposition method, and characterized by element analysis, TGA, FTIR, and morphology observation. The alumina coating layer had been proven to covalently bind to the surface of TiO2 through AlOTi bonds, which formed a continuous and dense coating layer, followed by forming a loose flocculent coating layer with the increase of alumina content. The alumina coating layer could significantly reduce the formation of carbonyl group on the LLDPE chains, and enhance UV aging resistance of LLDPE by inhibiting the photocatalytic activity of TiO2. Moreover, the dispersion of alumina‐coated TiO2 in the LLDPE matrix was improved. Thus, the transmittance of LLDPE/alumina‐coated TiO2 composites was reduced and the whiteness was improved. Importantly, the continuous and dense alumina coating layer was enough to inhibit the photocatalysis effect of TiO2 on LLDPE. The further increase of alumina coating content reduced the UV absorption capacity of alumina‐coated TiO2 and its compatibility with the LLDPE matrix. Therefore, the best alumina coating content on the surface of TiO2 was 1.46 wt% for preparing high performance LLDPE/TiO2 composites. Alumina‐coated TiO2 with controllable coating thickness was successfully synthesized. LLDPE/alumina‐coated TiO2 has excellent UV aging resistance and mechanical properties. The photocatalytic activity and UV absorption capacity of TiO2 could be regulated. 1.46 wt% of alumina coating is the best content for high performance LLDPE/TiO2 composites. [ABSTRACT FROM AUTHOR]

Metal nanoparticles (MNPs) stand out owing to conspicuous catalytic activity, optical and electromagnetic properties, with applications ranging from photocatalysis to biosensor and photoelectric devices. Although photocatalysis with TiO2 has emerged as a promising technique for preparing MNPs, the low photocatalytic efficiency of TiO2 limits its practical utilization. Herein, a rapid photoreduction approach is presented to prepare MNPs under UV and visible light based on polydopamine (PDA)/TiO2 composite surface. It found that the PDA‐modified TiO2 substrate can greatly enhance the photocatalytic efficiency and stability of MNPs, leading to rapid and highly‐controllable preparation of MNPs. By this method, various Ag, Au, and Pd patterns with controllable metallization degree can be easily fabricated. In addition, the substrate can be effectively recycled through rapid photobleaching. This method will have a promising future in the preparation of MNPs for various applications. [ABSTRACT FROM AUTHOR]

At present, the biphasic Li 2 TiO 3 –Li 4 SiO 4 ceramic pebbles with high lithium content and crushing load have been viewed as promising tritium breeders for maintaining the safety-state operation of the D-T fusion reactor. The tritium release behavior of Li 2 TiO 3 –Li 4 SiO 4 ceramic pebbles fabricated by centrifugal granulation method was investigated by using the Thermal Desorption Spectroscopy apparatus at Shizuoka University. It can be found that the Li 2 TiO 3 –Li 4 SiO 4 ceramic pebbles show three tritium release peaks, and most of the tritium was released as HTO observed from T-TDS spectra, and the peaks at 581 K and 734 K are mainly due to tritium release from Li 2 TiO 3 in core and shell. The peak at 813 K is mainly deemed as tritium release derived from the Li 4 SiO 4 shell. The content of tritium release from biphasic Li 2 TiO 3 –Li 4 SiO 4 ceramic is up to 11.5 MBq g−1, but the amount of gas species (HT) is only 0.126 MBq g−1. Besides, the isothermal heating experiment showed that the tritium release behavior was subject to diffusion process and de-trapping in defect sites. At the same time, the irradiation defects of E′-center, O-related center, and Ti3+ for breeding material can be found by using an ESR device, and the isochronous heating experiments have manifested that the amount of irradiated defect decreases as heating temperature increases, which indicates that the tritium release behavior is closely related to defect annihilation process. Therefore, the advanced Li 2 TiO 3 –Li 4 SiO 4 ceramic breeder can be fabricated based on tritium release result, which will be conducive to meet the practical application of breeder in the future. [ABSTRACT FROM AUTHOR]

Phosphors-in-glass films (PiGFs) with thermally conductive substrates are considered to be an efficient color inorganic color conversion material for laser lighting. However, due to the contradiction between the light extraction and heat dissipation, achieving high brightness and excellent color quality simultaneously is still a big challenge. Herein, a unique architecture of bicolor PiGF with highly reflective interface design was proposed for high-quality laser lighting. The TiO 2 -glass films with different thicknesses were prepared on highly heat-conducting AlN substrates to obtain the TiO 2 –AlN (TA) substrates with various reflectance. In addition, mixed green/red, stacked green-red, and stacked red-green phosphor glass films were printed and sintered on the TA substrates to prepared three bicolor PiGF converters of M-PiTA, G-R-PiTA, and R-G-PiTA. At the TiO 2 -glass film thickness of 100 μm, the M-PiTA enables a luminous flux of 2053 lm@24.8 W/mm2, which is 1.9 times that of traditional M-PiGF-AlN converter (1077 lm@17.6 W/mm2). The M-PiTA converter realizes a high-quality white light with a CRI of 82.7 and a chromaticity coordinate of (0.3378, 0.3297). Furthermore, the M-PiTA converter enables higher luminance and light quality compared with the stacked G-R-PiTA and R-G-PiTA converters. With the laser power of 4.2 W, the working temperature of M-PiTA converter is only 59.2 °C, while that of R-G-PiTA and G-R-PiTA converters rises to 499 °C and 301 °C. The results demonstrate that the bicolor PiTA converters have broad prospects in the application of laser lighting. [ABSTRACT FROM AUTHOR]

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]

Bimetallic oxide nanoparticles (NPs) have gained the interest of researchers owing to the synergistic mechanism of action by the elements present. Mycosynthesis of nanostructures is a promising, facile, and an environmentally friendly approach. In the present study, CuO/TiO 2 NPs were produced using the cell-free filtrate of the endophytic fungus Trichoderma virens. The reaction of the fungal filtrate with the two metal salts, CuSO 4.5H 2 O and TiO 2 , resulted in the mycosynthesis of the CuO/TiO 2 NPs. The prepared bimetal oxide NPs were characterized using XRD, FTIR spectroscopy, EDX, DLS, zeta potential analysis, XPS, Raman scattering, FESEM, and HRTEM. The mycosynthesized CuO/TiO 2 NPs exhibited diffraction peaks characteristic of the monoclinic CuO and tetragonal rutile TiO 2 crystal planes. Homogeneity and stability were observed as a result of the biological moieties present in the fungal filtrate, which capped the CuO/TiO 2 NPs. The prepared CuO/TiO 2 NPs were distributed as flake/plate-like and quasi-spherical/nanorod CuO and TiO 2 NPs, respectively. A broad-spectrum antibacterial effect was recorded, with zones of inhibition as follows: foodborne pathogens Escherichia coli (14.34 mm), Salmonella enterica serovar Typhimurium (11.32 mm), and Staphylococcus aureus (9.63 mm); and phytopathogenic bacteria involving Clavibacter michiganensis subsp. michiganensis (Cmm , 12.16 mm), C. michiganensis subsp. capsici (Cmc , 11.26 mm), wild type and streptomycin-resistant Pectobacterium carotovorum subsp. carotovorum (Pcc , 11.06 and 12.37 mm, respectively), and wild type and streptomycin-resistant Xanthomonas citri pv citri (Xcc , 12.48 and 12.69 mm, respectively). The minimum inhibitory concentrations (MICs) and minimum bactericidal concentrations (MBCs) of the CuO/TiO 2 NPs were determined using the broth microdilution assay. NP-treated bacterial cells at sub-MICs had rough surfaces with membrane defects and exhibited shrinkage, reduction of cell edges, cracks, and fractures on their surfaces. This study provides insights into the potential of the mycosynthesized CuO/TiO 2 NPs as alternative nano-antimicrobial agents, which could be employed for future biomedical, agricultural, and pharmaceutical applications. [Display omitted] [ABSTRACT FROM AUTHOR]

The construction of heterojunction photocatalysts is an excellent strategy for treating wastewater. Herein, a three-dimensional nanoflower-like TiO 2 /WO 3 heterojunction photocatalyst was synthesized in situ on the surface of pure Ti substrate by plasma electrolyte oxidation (PEO) combined with a subsequent process, and the abundant network topology and lattice defects improved the adsorption performance of the photocatalyst. The construction of Z-scheme heterojunction not only promotes the separation of photogenerated carriers, but also enhances the light absorption ability and greatly improves the photocatalytic performance of photocatalysts. Under the synergistic effect of adsorption and photocatalysis, the degradation rate of MB reached 86.2 % in 2 h, which was significantly higher than that of the single-component photocatalyst. Finally, the synthesis of TiO 2 /WO 3 heterojunction photocatalysts by this process and the reaction mechanism of heterojunction photocatalysts for the degradation of organic dyes were illustrated by combining experiments and DFT calculations. In conclusion, this study opens up a new process for synthesizing Z-scheme heterojunction photocatalysts, which brings new insights for photocatalytic treatment of water pollution. [ABSTRACT FROM AUTHOR]

To improve the biological fouling and corrosion resistance of Ti6Al4V (TC4) in marine environments, copper-containing titanium dioxide (TiO 2 (Cu)) films were prepared by magnetron sputtering TiO 2 (Cu) powder targets. The morphologies of the films showed that they became rough and coarse from 1.6 nm of the TiO 2 film to approximately 9 nm of the TiO 2 (Cu) films, which might be owing to the increase in the deposition rates from 1.33 to 2.08 nm/min. No diffraction orientations of the TiO 2 and Cu phases were found compared to those of the TiO 2 (Cu) powder. Ti, O, and Cu were detected using X-ray photoelectron spectroscopy to confirm the composition of the films. The ratio of Cu2+ increased as the Cu content of the films increased, whereas that of Cu/Cu + scarcely changed. The TiO 2 and TiO 2 (Cu) films exhibited photocatalytic effects and their photocatalytic intensities decreased as the Cu content increased. Hydrophobicity was enhanced by the addition of Cu to the film. The antibiological fouling effect of the TiO 2 (Cu) films remained unchanged as the Cu/Ti ratio varied. Compared with those of TC4, the corrosion current densities of the TiO 2 (Cu) films decreased by one order of magnitude and the corrosion potentials increased by 350 mV in artificial seawater, indicating that the corrosion resistance of TiO 2 (Cu)/TC4 was improved. Importantly, Cu was in abundance in the films for both antibiological and corrosion resistance functions owing to the saturated ratio of Cu/Cu+ irrespective of the Cu/Ti ratio in the films. [ABSTRACT FROM AUTHOR]

Biodiesel is an eco-friendly, renewable alternative fuel, and it can be obtained from soybean oil, vegetable oils, animal fat, or microalgae. This study presents a comprehensive investigation into the production and characterization of microalgae biodiesel utilizing multiple analytical techniques, including CHNSO analysis, Fourier-transform infrared spectroscopy (FTIR), gas chromatography--mass spectrometry (GC--MS), and proton nuclear magnetic resonance spectroscopy (¹H NMR). The CHNSO analysis revealed the elemental composition of biodiesel blends, highlighting the effects of TiO2 nanoparticle concentrations on carbon, nitrogen, sulfur, and oxygen content. With increasing TiO2 concentration, a steady increase in the carbon content and a gradual decrease in the nitrogen content were observed. According to the CHNSO analysis, the sulfur content of blended biodiesel was found to be lower than that of fossil diesel, with an empirical formula of CH2.26N0.000584S0.000993O0.0517. FTIR and 1H NMR spectroscopy confirmed the synthesis of biodiesel. Fouriertransform infrared resonance confirmed the presence of ester groups at 1732 cm-1, and a prominent peak at 1,455 cm-1 indicated a higher carbon content in the blended biodiesel. GC--MS analysis identified compounds of fatty acid methyl esters (FAMEs) and hydrocarbons. The major components of FAMEs were 9-octadecenoic acid methyl ester (C19H36O2), linoleic acid ethyl ester (C20H36O2), and hexadecanoic acid methyl ester (C17H34O2), with compositions 20.65%, 9.67%, and 6.26%, respectively. The presence of methyl ester in the blended fuel suggests its potential as an alternative fuel source. [ABSTRACT FROM AUTHOR]

Oxidative stress (OS) resulting from excessive reactive oxygen species (ROS) is the initial pathogenesis of many diseases, thus various pharmaceutical materials are explored to scavenge ROS. However, the medical applications of most ROS‐scavenging materials are limited due to side effects and low bio‐stability. DNA has emerged as a promising ROS‐scavenging material with excellent biosafety and programmability, but the efficiency needs to be improved by developing new fabrication methods. Here, a sub‐nanoscale TiO2 composite modified with DNA with excellent biostability, biocompatibility, and enhanced ROS‐scavenging efficiency for medical applications is presented. The sub‐nanoscale TiO2‐DNA (SNTD) composite exhibits higher scavenging capacities for multiple ROS including ·OH, H2O2, and O2•−. Additionally, it can regulate macrophages from pro‐inflammatory to anti‐inflammatory phenotype. In vivo experiments show that the nanocomposites reduce ROS concentration, decrease inflammatory cell infiltration, accelerate re‐epithelization, and promote collagen regeneration, thereby enhancing the healing of infected skin wounds. [ABSTRACT FROM AUTHOR]

Modern cosmetic products, with rich formulations of components, have become an ideal breeding ground for microorganisms. Implementing effective preservative systems is crucial to prevent microbial growth and contamination. Titanium dioxide nanoparticles, a familiar ingredient in cosmetics, can decompose the outer membrane of microbial cells by producing free radicals. Chitosan has shown antimicrobial activities by impairing cell wall integrity by binding to it aiding in the release of cytosolic contents. In line with this, this work was centered on evaluating the antimicrobial efficiency of chitosan-coated titanium dioxide (CS-TiO2) nanoparticles against three bacterial species viz. Pseudomonas aeruginosa (P. aeruginosa), Staphylococcus aureus (S. aureus) and Escherichia coli (E. coli) and use them as a self-preservative agent in cosmetic formulations. The growth curve analysis exhibited a dose-dependent delay in bacterial growth. The minimum inhibitory concentration (MIC50) results revealed that the nanoparticles were effective at 31.25μg/ml and 62.5μg/ml concentrations in suppressing S. aureus, P. aeruginosa and E. coli, respectively. The redox imbalance, membrane lipid peroxidation, DNA damage and cell viability analyses showed that the CS-TiO2 nanoparticles could disrupt the membrane leading to reactive oxygen species (ROS) formation and altering the genetic material. Therefore, the conclusions drawn from this research highlight the proficient microbial performance of CS-TiO2, proposing its suitability for incorporation into consumer products, especially cosmetics. As far as the authors are aware, this study is believed to be the first to investigate the potential of CS-TiO2 nanoparticles as a self-preservative. [ABSTRACT FROM AUTHOR]

This study investigates the influence of LED radiation intensity on the photodeposition of gold nanoparticles onto TiO2 substrates, examining their physicochemical properties and photocatalytic activities. Utilizing a range of radiation intensities and wavelengths, TiO2-Au composites were synthesized and characterized through techniques such as X-ray diffraction (XRD), scanning electron microscopy (SEM) with energy dispersive X-ray (EDX), and X-ray photoelectron spectroscopy (XPS). The deposition process, markedly enhanced by shorter wavelengths and higher intensities, efficiently formed gold nanoparticles. This research distinctly highlights observable morphological changes in the nanoparticles; increased radiation intensity not only augmented the size but also altered their shape from spherical to hexagonal. These morphological transformations significantly improve the composites' light absorption and catalytic properties due to the surface plasmon resonance of the gold nanoparticles. Photocatalytic assessments, using metronidazole as a model pollutant, demonstrated that composites prepared with higher LED intensities showed significantly enhanced degradation capabilities compared to those synthesized with lower intensities. The findings underscore that manipulating photodeposition parameters can critically influence the structural and functional properties of TiO2-Au composites, potentially advancing their applications in environmental remediation and solar energy utilization. [ABSTRACT FROM AUTHOR]

Hydrogen energy, recognized as a pivotal clean energy source, has attracted considerable attention in the realm of photocatalytic hydrogen production. Nevertheless, inorganic materials were difficult to regulate band gaps, resulting in limited photogenerated carrier rates. Additionally, organic materials frequently suffer from insufficient stability and a propensity for electron recombination. Therefore, fully utilizing the interface effect will become an important breakthrough for novel and efficient catalysts. Herein, hydroxylate covalent organic frameworks (H-COFs) were formed by direct synthesis method, in addition, titanium dioxide (TiO 2) was used as an inorganic substrate, and TiO 2 was transformed titanium acid under weakly acidic conditions, meanwhile, chloride covalent organic frameworks (C-COFs) growth on TiO 2 surface by interface effect when H-COFs were formed into C-COFs under titanium acid. The structure characteristics, photoelectric performance, bandgap width and stability of C-COFs/TiO 2 were confirmed through characterization analysis. C-COFs/TiO 2 exhibit strong stability, conjugation effects, electron deficiency effects, and catalytic efficiency. Hydrogen production rate up to 5598 μmol g−1 h−1 by C-COFs/TiO 2 as photocatalyst. C-COFs/TiO 2 lead to 161 times improvement in photocatalytic activity for TiO 2 and 3.6 times improvement in photocatalytic activity for H-COFs. The catalytic reaction mechanism was obtained by utilizing experimental data and DFT calculation. This synergistic integration of organic inorganic combined catalyst provides a foundational framework for advancing research into novel photocatalysts. [Display omitted] • Chloride COFs growth on TiO 2 surface by interface effect when H-COFs were formed into C-COFs under titanium acid. • C-COFs/TiO 2 catalysts with electronic transmission channel was synthesized for the first time. • C-COFs/TiO 2 exhibit strong stability, conjugation effects, electron deficiency effects, and catalytic efficiency. • The reaction mechanism can be proposed by experimental and DFT calculations. [ABSTRACT FROM AUTHOR]

Purpose: To develop a biocompatible denture base resin/TiO2 nanocomposite material with antifungal characteristics that is suitable for 3D‐printing denture bases. Materials and Methods: TiO2 nanoparticles (NPs) with a 0.10, 0.25, 0.50, and 0.75 weight percent (wt.%) were incorporated into a commercially available 3D‐printed resin material. The resulting nanocomposite material was analyzed using Lactate dehydrogenase (LDH) and AlamarBlue (AB) assays for biocompatibility testing with human gingival fibroblasts (HGF). The composite material was also tested for its antifungal efficacy against Candida albicans. Fourier transform infrared (FTIR) and Energy Dispersive X‐ray Spectroscopy (EDX) mapping were conducted to assess the surface coating and the dispersion of the NPs. Results: LDH and AB assays confirmed the biocompatibility of the material showing cell proliferation at a rate of nearly 100% at day 10, with a cytotoxicity of less than 13% of the cells at day 10. The concentrations of 0.10, 0.25, and 0.50 wt.% caused a significant reduction (p < 0.05) in the number of candida cells attached to the surface of the specimens (p < 0.05), while 0.75 wt.% did not show any significant difference compared to the control (no TiO2 NPs) (p > 0.05). FTIR and EDX analysis confirmed the presence of TiO2 NPs within the nanocomposite material with a homogenous dispersion for 0.10 and 0.25 wt.% groups and an aggregation of the NPs within the material at higher concentrations. Conclusion: The addition of TiO2 NPs into 3D‐printed denture base resin proved to have an antifungal effect against Candida albicans. The resultant nanocomposite material was a biocompatible material with HGFs and was successfully used for 3D printing. [ABSTRACT FROM AUTHOR]

Aerospace and automotive industries, among others, utilize reinforced aluminium metal matrix composite materials extensively. Aluminium alloy 5052 matrix was reinforced with tungsten carbide and titanium dioxide particulate reinforcements by varying their weight fractions, to fabricate the hybrid composites. The melt‐stir casting route was used to process the materials, and their characteristics were determined by measuring Vickers microhardness, tensile strength and peak elongation. The cost‐effectiveness and productivity of the melt‐stir casting route led to its selection. Investigations were carried out to assess how reinforcement particles were mixed into the aluminium alloy matrix using scanning electron microscopy and energy‐dispersive x‐ray analysis. The microstructure of aluminium alloy 5052 showed a distinct homogenous structural integrity. Adding tungsten carbide and titanium dioxide particles to aluminium alloy 5052 led to a 6.57 % rise in the Vickers microhardness value. The tensile strength of the hybrid composites made of aluminium, tungsten carbide, and titanium dioxide increased by as much as 8.7 %. The findings demonstrated that all of the hybrid composites failed due to particle fracture and ductile fracture in the case of the as‐cast aluminium alloy 5052. [ABSTRACT FROM AUTHOR]

A one‐pot synthesis of plasmonic gold‐modified TiO2 nanocomposites is reported by using glucose reduction of HAuCl4 in presence of titanium tetraisopropoxide. The resulting nanocomposites are characterized by thermal‐gravimetric analyses, X‐ray diffraction combined with X‐ray fluorescence and photoelectron spectroscopies. A binary system of β‐TiO2 and anatase phases is obtained for low Au content while only anatase form is favored when the initial Au rate rises. This investigation also suggests the inclusion of gold in the TiO2 structure. Although the optical bandgap of the different nanocomposites remains around 3 eV, the increase of Au content induces a shift of both valence and conduction edge bands to lower energy levels. The photocatalytic activity of TiO2/Au nanocomposites is assessed through the decolorization of different cationic and anionic dyes as model compounds. Regarding rhodamine and methylene blue dyes, the sample TiO2 modified with 3.5 wt% of Au presents the best performance. The relation between the structure of the nanocomposites and their capacity to degrade pollutants is discussed. [ABSTRACT FROM AUTHOR]

A highly active rfi()2 photocatalyst with exposed |(X)1 crystal faces was prepared by a one pot hydrothermal method using titanium sulfate as the titanium source and hydrofluoric acid as the morphology control agent. The photocatalyst was charartcrizcd by SEM, TEM, XK1), XI*S, etc・ Tlw cfleet of factors such as the ratio of raw materials, reaction temperature, and reaction time on the degradation efficiency of Tig photocatal)-st was investigated with mrthyl orange dye as the target degradation product. The results showed that when F/TI was 1. O, th<* hydrothermal reaction temperature was 180 Y: , and the hydrothermal reaction time was 12 h, the IKh sample prepared could achieve a degradation rate of 92. 5% for mrthyl orange. J'hc photocatalytic degradation of mrthyl orange by UKX fbllou's a first-order kinetic process. [ABSTRACT FROM AUTHOR]

Hybrid materials (HMs) combine the high diversity of functionalities of organic compounds with properties typical for inorganic materials, such as high mechanical strength or high thermal stability. Herein, HMs combining organic pigment molecules and TiO2 as inorganic component, with covalently linked components, i.e., so‐called class II HMs, are reported. The synthesis of such HMs is intrinsically challenging, as the apolar organic pigment component and the inorganic polar TiO2 component require different conditions for their respective formation. Herein, we circumvent this issue by employing solvothermal synthesis in superheated isopropanol, which through temperature tunability of the solvent properties allows for both generating and linking both components in one‐pot. First, it is shown that an organic benzimidazole‐based pigment molecule designed for readily binding to Ti can be synthesized solvothermally. Second, new class II titanium‐based HMs are generated from Ti(OiPr)4 and pigment precursors in a solvothermal reaction. The pigment@TiO2 HMs feature significant porosity and are structurally identified as layered structures of lepidocrocite‐like TiO2 linked via pigment molecules. These layered HMs assemble into hierarchical nanoflowers, and depending on the pigment segments, different interlayer spacings in between inorganic layers are observed. Third, the pigment@TiO2 materials are shown to be usable as electrode materials in lithium‐ion batteries. [ABSTRACT FROM AUTHOR]

Selective synthesis of furfuryl alcohol from furfural conversion via semiconductor photocatalytic route has appeared as a promising solution for transforming biomass into high‐value‐added products under mild temperature and pressure conditions. Titanium dioxide (TiO2) photocatalysts were prepared by a simple sol‐gel method followed by a calcination treatment ranging from 500–1000 °C, resulting in materials with distinct physicochemical properties. The photocatalytic efficiency of the TiO2 samples was examined in the selective production of furfuryl alcohol from furfural under UV‐LED irradiation. The influence of various organic solvents, including ethanol, methanol, 2‐propanol, and acetonitrile, was evaluated to optimise the selectivity towards furfuryl alcohol production. Photocatalysts with larger anatase to rutile ratio and increased density of oxygen vacancies (defects) exhibited superior performance for furfuryl alcohol production. The presence of these defects on the catalyst surface leads to a significant enhancement in the photocatalytic efficiency by acting as crucial active sites. Among the TiO2 samples, the highest conversion of furfural into furfuryl alcohol was observed with the TiO2 sample calcined under an air atmosphere at 600 °C (TiO2‐600), achieving 85 % yield and 100 % selectivity for furfural after 30 min reaction using ethanol as solvent. [ABSTRACT FROM AUTHOR]

The RuO2/TiO2 composite catalyst was prepared by wet immersion method combined with heat treatment process, and its structure was characterized by X-ray diffraction （XRD） and scanning electron microscopy（SEM）. Analyze the photocatalytic effect of the composite catalyst under different conditions such as the amount of RuO2 solution, light intensity, pH of methyl orange solution, and ventilation rate. The results showed that the doping of RuO2 did not significantly change the crystal plane structure of TiO2. As the mass fraction of RuO2 increased, the sample particle size first increased and then decreased, reaching an ideal equilibrium point at a 0. 15% addition amount. When the amount of RuO2 solution is 0. 15% mass fraction and the light intensity is 4. 23 mW/cm2, the degradation rate of methyl orange reaches 65%, indicating a high photocatalytic effect. When the methyl orange solution is acidic, a more ideal photocatalytic effect can be achieved. When preparing the composite catalyst, the photocatalytic effect is better when the calcination temperature is 550 ℃. However, ventilation is not the key factor affecting the photocatalytic effect. It aims to provide valuable references for the preparation and application of RuO2/TiO2 composite catalysts [ABSTRACT FROM AUTHOR]

The extensive global use of rubber results in significant microplastic pollution from the release of tire wear particles and microplastic leachate, impacting the environment, human health, and ecosystems. Waste tires are normally recycled and used for the production of new products, such as rubber tiles. The presented study aims to show the possibility of further decrease in the negative environmental impact of materials based on recycled rubber. This paper presents the modification of rubber tiles with a titanium dioxide (TiO2) coating, focusing on surface integrity, rubber particle wear release, and the consequent environmental impact of leachate release. Both reference and modified rubber tiles were subjected to artificial accelerated aging in a solar simulator for 4, 6, and 8 weeks, followed by an abrasion test. The carbonyl index was calculated from FTIR characterization after each time frame to indicate the degradation of organic compounds and chemical changes caused by UV exposure. A 24 h leaching test with a liquid-to-sample ratio of 1:20 was performed on both rubber tile samples prior to and after 8 weeks of aging along with the aged wear particles for the purpose of the non-target screening of released organic leachate by LC/MS QTOF. The results of carbonyl indices showed that the TiO2 coating contributes to the stabilization of polymer degradation and, to a certain extent, reduces the leaching of organic compounds, such as phthalates. However, the increased wear and release of rubber particles and the subsequent degradation of organic leachates require further in-depth research. [ABSTRACT FROM AUTHOR]

Doping titanium dioxide has become a strategy for enhancing its properties and reducing its recombination issues, with the aim of increasing its efficiency in photocatalytic processes. In this context, this work studied its deposition over glass substrates using a sol–gel dip coating methodology. The effect of doping TiO2 with Zirconium cations in low molar concentrations (0.01, 0.05, 0.1%) in terms of its structural and optical properties was evaluated. The structural characterization confirmed the formation of amorphous thin films with Zr introduced into the TiO2 cell (confirmed by XPS characterization), in addition to increasing and defining the formed particles and their size slightly. These changes resulted in a decrease in the transmittance percentage and their energy band gap. Otherwise, their photocatalytic properties were evaluated in hydrogen production using ethanol as a sacrificial agent and UV irradiation. The hydrogen evolution increased as a function of the Zr doping, the sample with the largest Zr concentration (0.1% mol) being the most efficient, evolving 38.6 mmolcm−2 of this gas. Zr doping favored the formation of defects in TiO2, being responsible for this enhancement in photoactivity. [ABSTRACT FROM AUTHOR]

The formation of Paleozoic silica–iron-rich sedimentary rocks in the Urals volcanic-hosted massive sulfide (VHMS) deposits is considered a result of seafloor alteration of hyaloclastites mixed with calcareous/organic or sulfide material. These rocks host various Ti mineral phases pointing to the transformation of precursor metacolloidal TiO2 phases to disordered anatase during seafloor alteration of hyaloclastites, which was later converted to globules and clusters and further to diagenetic rutile. The LA-ICP-MS analysis showed that the Ti content of hyaloclasts partly replaced by finely dispersed Si–Fe aggregates increases to 540–2950 ppm and decreases (<5 ppm) in full Si–Fe pseudomorphs after hyaloclasts. LA-ICP-MS element mapping reveals the enrichment in V, U, Cr, W, Nb, Pb, and Th of the anatase globules and the local accumulation of Zr, Y, and REE on their periphery. Corrosive biogenic textures in the outer zones of some hyaloclasts and biomorphic aggregates in rocks contain anatase particles in assemblage with apatite indicating the biophilic properties of Ti. This work fills the knowledge gaps about Ti mobilization during low-temperature seafloor alteration of hyaloclastites in VHMS deposits. [ABSTRACT FROM AUTHOR]

In this study, original titanium dioxide (TiO2) and cerium (Ce)-doped TiO2 nanorod array photoanodes are prepared by hydrothermal method combined with high-temperature annealing, and their morphology, photoelectrochemical properties, and photocatalytic hydrogen production ability are systematically evaluated. X-ray diffraction (XRD) analysis shows that as the Ce content increases, the diffraction peak of the rutile phase (110) shifts towards lower angles, indicating the successful doping of different contents of Ce into the TiO2 lattice. Photoelectric performance test results show that Ce doping significantly improves the photocurrent density of TiO2, especially for the 0.54wt% Ce-doped TiO2 (denoted as CR5). The photocurrent density of CR5 reaches 1.98 mA/cm2 at a bias voltage of 1.23 V (relative to RHE), which is 2.6 times that of undoped TiO2 (denoted as R). Photoelectrochemical hydrolysis test results show that the hydrogen yield performance under full-spectrum testing conditions of Ce-doped TiO2 photoanodes is better than that of original TiO2 as well, which are 37.03 and 12.64 µmol·cm−2·h−1 for CR5 and R, respectively. These results indicate that Ce doping can effectively promote charge separation and improve hydrogen production efficiency by reducing resistance, accelerating charge transfer, and introducing new electronic energy levels. Our findings provide a new strategy for designing efficient photocatalysts with enhanced photoelectrochemical (PEC) water-splitting performance. [ABSTRACT FROM AUTHOR]

Biodiesel is a renewable and sustainable alternative fuel to petrol-derived diesel. Decreasing the operating costs by improving the catalyst's characteristics is an effective way to increase the competitiveness of biodiesel in the fuel market. An aqueous solution of sodium methoxide (CH3ONa), which is a traditional alkaline catalyst, was immersed in nanometer-sized particles of titanium dioxide (TiO2) powder to prepare the strong alkaline catalyst TiO2/CH3ONa. The immersion method was used to enhance the transesterification reaction. The mixture of TiO2 and CH3ONa was calcined in a high-temperature furnace in a range between 150 and 450 °C continuously for 4 h. The heterogeneous alkaline catalyst TiO2/CH3ONa was then used to catalyze the strong alkaline transesterification reaction of palm oil with methanol. The highest content of fatty acid methyl esters (FAMEs), which amounted to 95.9%, was produced when the molar ratio of methanol to palm oil was equal to 6, and 3 wt.% TiO2/CH3ONa was used, based on the weight of the palm oil. The FAMEs produced from the above conditions were also found to have the lowest kinematic viscosity of 4.17 mm2/s, an acid value of 0.32 mg KOH/g oil, and a water content of 0.031 wt.%, as well as the highest heating value of 40.02 MJ/kg and cetane index of 50.05. The lower catalyst amount of 1 wt.%, in contrast, resulted in the lowest cetane index of 49.31. The highest distillation temperature of 355 °C was found when 3 wt.% of the catalyst was added to the reactant mixture with a methanol/palm oil molar ratio of 6. The prepared catalyst is considered effective for improving the fuel characteristics of biodiesel. [ABSTRACT FROM AUTHOR]

Titanium dioxide (TiO2) catalysts are primarily utilized under ultraviolet light, and their potential in industrial applications remains largely untapped. To address this issue, our study uses a one-pot impregnation method to prepare a series of In-TiO2/TSS(X) (TSS, Tobacco stem silk. X, the molar ratio of In/Ti) catalysts. Among them, the degradation performance of the In-TiO2/TSS(2.0) material increased from 13.8% for TiO2 to an impressive 92.9%. By establishing a first-order kinetic model, it was determined that the degradation performance of the In-TiO2/TSS(2.0) material surpassed that of TiO2 by a factor of 24. Structural characterization revealed that the introduction of tobacco stem silk templates did not alter the crystal phase of TiO2 and that the main component of the catalyst remained TiO2. Not only that, an O–In structure formed on the surface of the TiO2, leading to a significant increase in the material's specific surface area. Furthermore, principle tests were conducted, revealing significant enhancements in its light absorption capacity, intensity, and photocurrent density. Through active species trapping experiments, it was observed that, in the photocatalytic degradation process of this catalyst series, holes (h+) played the primary role, while the hydroxyl ion (·OH) and superoxide ion (·O2−) acted as auxiliary species. [ABSTRACT FROM AUTHOR]

Recently, many researchers have made progress in studies aimed at enhancing the power conversion efficiency (PCE) of n-type dye-sensitized solar cells (DSSCs). This paper presents a systematic investigation focused on improving the PCEs of n-type DSSCs by synthesizing TiO2 nanoparticle active layers and varying their thickness. The study found that increasing the TiO2 layer thickness up to 17 µm resulted in a steady 41% increase in PCE, primarily owing to the enhanced photocurrent density in the n-type DSSCs. This improvement is attributed to the enhanced light harvesting effect. As a result, n-type DSSC with 17 µm thick TiO2 layer demonstrates a relatively high Jsc value of 8.42 mA/cm2, achieving an overall PCE of 4.02%. In contrast, the n-type DSSC with a 6 µm thick TiO2 layer exhibits a much lower Jsc value of 5.55 mA/cm2, leading to a reduced PCE. This result represents at least a 52% increase in current density, indicating that the optimal thickness of the TiO2 active layer is a critical factor influencing the PCE of DSSCs. [ABSTRACT FROM AUTHOR]

The photoinduction process in a p-n heterogeneous structure should be in correlation with the electronic properties of its semiconductor components. Based on that assumption, a double layer made of polyaniline (PANi) and titanium dioxide (TiO2) on glass substrate is used to investigate the charge photogenerated and transferred in the structure. The PANi layer is made by in situ polymerization of aniline in HCl acidic aqueous medium, while the TiO2 layer is made by thermolysis of TiCl3 dilute solution. It has been found that the PANi/TiO2 double layer is a composition of a PANi emeraldine salt layer (p-type semiconductor) covered by a TiO2 rutile layer (n-type conductor), creating a p-n heterogeneous structure. Upon exposure to the excitation light, the light sensitivity of the PANi layer in the PANi/TiO2 structure reveals a response mode distinct from those of the neat PANi layer. The conductance of the PANi layer in the coupling structure shows two modes of response: (1) a negative mode, i.e., a decrease in conductance in response to the excitation light of wavelength 369, 396 and 447 nm, and (2) a positive mode, namely an increase in conductance, as with the excitation light of wavelength 667 nm. On the other hand, the neat PANi layer simply shows a single positive response to excitation light. Those response modes account for a modulation of the PANi/TiO2 depletion region that in turn depends upon the photoexcited electrons and holes in the heterostructure. The diffusion of excess photogenerated electrons and holes over the heterojunction results in an expansion or reduction of depletion width that gives rise to an increase or decrease of the PANi layer conductance, i.e., a positive or negative response, respectively. In addition, the negative mode in response to the excitation light of wavelength 447 nm (~2.8 eV) is assumed to be an impact of the PANi in extending the photoinduction of the TiO2 component into the vision range at the blue region. [ABSTRACT FROM AUTHOR]

Background: Recent developments in nanotechnology have provided efficient and promising methods for the treatment of diseases to achieve better therapeutic results and lower side effects. Titanium dioxide (TiO2) nanomaterials are emerging inorganic nanomaterials with excellent properties such as low toxicity and easy functionalization. TiO2 with special nanostructures can be used as delivery vehicles for drugs, genes and antigens for various therapeutic options. The exploration of TiO2-based drug delivery systems shows great promise for translating nanotechnology into clinical applications; Methods: Comprehensive data on titanium dioxide were collected from reputable online databases including PubMed, GreenMedical, Web of Science, Google Scholar, China National Knowledge Infrastructure Database, and National Intellectual Property Administration; Results: In this review, we discuss the synthesis pathways and functionalization strategies of TiO2. Recent advances of TiO2 as a drug delivery system, including sustained and controlled drug release delivery systems were introduced. Rigorous long-term systematic toxicity assessment is an extremely critical step in application to the clinic, and toxicity is still a problem that needs to be closely monitored; Conclusions: Despite the great progress made in TiO2-based smart systems, there is still a great potential for development. Future research may focus on developing dual-reaction delivery systems and single-reaction delivery systems like redox and enzyme reactions. Undertaking thorough in vivo investigations is necessary prior to initiating human clinical trials. The high versatility of these smart drug delivery systems will drive the development of novel nanomedicines for personalized treatment and diagnosis of many diseases with poor prognosis. [ABSTRACT FROM AUTHOR]

The aim of this study is to use recycled waste materials to modify the performance of composites used as dental fillings. For this purpose, depolymerized polyethylene terephthalate (DPET) polymers were prepared by recycling waste polyethylene terephthalate (PET) using the glycolysis process. DPET was then blended with polymethyl methacrylate (PMMA) at different weight percentages. Polymer blends were subjected to mechanical, physical, and biological tests. It is evident that PMMA blended with a 5 wt% of DPET exhibits the highest compressive strength which is approximately two times that obtained from neat PMMA, highlighting the suitability of these resins to replace amalgam and to be considered for dental restorations. It was also found that the water absorption of the blends investigated is relatively stable at 5 wt% DPET. The SEM images showed no distinguishable phases, highlighting the high compatibility between DPET and PMMA. The biological tests, including in vitro cytotoxicity, showed that the cell viability mean values of PMMA containing 5 wt% DPET is higher than that of control group. Interestingly, in dental practice, the reliable in vitro cytotoxic approach is considered as an important aid in clinical procedures in the use of dental filling systems. The microbiology study has shown that the inhibition zones against Streptococcus mutans of PMMA: 5 wt% DPET is higher than the control group. According to the obtained results, the blend of PMMA: 5 wt% DPET was selected as an optimum blend, which was then reinforced with various weight percentages of nano-sized titanium dioxide (TiO2). The composites were then tested under compression, microhardness, and impact tests. The results demonstrated the significant impact of TiO2 on enhancing the properties of the composites investigated. This can provide a new protocol for synthesizing nanocomposite materials for dentistry. [ABSTRACT FROM AUTHOR]

Background: Dark‐skinned individuals (DSI) present high rates of melasma and post‐inflammatory hyperpigmentation. The use of sunscreens with mineral filters is essential for prevention and treatment. Our objective was to determine the preferences of dermatologists and dermatology residents in the prescription of sunscreens for DSI. Methods: An anonymous survey of attendees at an online photoprotection event held on March 31, 2022, in Spain. Results: The survey was answered by 66.6% (221/332) of the attendees: 159 dermatologists (71.9%) and 62 dermatology residents (28.1%). Respondents reported recommending the use of sunscreen to a median of 80% of DSI [interquartile range (IQR), 50–90]. Physicians reported prescribing tinted sunscreens to a median percentage of 60% (IQR, 25–90) of DSI with acne; and to a median percentage of 90% (IQR, 58–99) of DSI with melasma. The most prescribed photoprotectors to DSI with melasma were organic broad‐spectrum sunscreens with antioxidants: 102/220 (46.4%) and mineral broad‐spectrum sunscreens (with iron oxides): 45/220 (20.4%). In DSI with melasma or other pigmentary disorders, the most preferred features of sunscreens were as follows: sun protection factor ≥ 30: 217/221 (98.2%), UVA protection: 214/221 (96.8%), color for camouflage: 150/220 (68.2%) and mineral filters such as titanium dioxide and zinc oxide: 151/220 (68.6%) or iron oxides: 131/220 (59.5%). Limitations: Online survey, potential inclusion bias. Conclusions: Respondents reported to prescribe sunscreens to the majority of DSI, and tinted sunscreens for the majority of DSI with pigmentary disorders. However, the most frequently recommended sunscreens for DSI were organic broad‐spectrum sunscreens with antioxidants. [ABSTRACT FROM AUTHOR]

Nanoparticles of titanium dioxide (NPs-TiO2) are used in several industries, with common applications due to their surface photocatalytic effect. An alternative use is the TiO2 addition to partially replace white Portland cement (WPC) to maintain the reflectivity surface over time. However, although it is known that the TiO2 addition influences the reaction kinetics of Portland cement, there are still literature controversies about how this material's physical, chemical, and mineralogical characteristics affect this dynamic. Therefore, this paper aims to monitor the chemical reaction after adding NPs-TiO2 in WPC suspensions and discuss its effect on the hydration process concerning TiO2 characteristics and the addition content. For this purpose, two TiO2 samples with distinct mineralogical characteristics—pure anatase (TiPC105) and a combination of rutile and anatase (TiP25)—were used. The evolution of hydration kinetics was analyzed by calorimetry, while XRD analyzed the suspension's mineralogy over time, and the hydrated compounds were quantified by thermogravimetry. It was found that the physical characteristics of the particles are more important for the suspension's reaction kinetics than their mineralogical characteristics. However, in early hydration, adding finer NPs-TiO2 did not lead to higher heat flow rates due to their tendency to agglomerate, reducing their effective surface area and consequently the area available for the precipitation of new hydrates. After a certain period, however, the trend usually found in literature prevails, with finer particles leading to higher reactivity. [ABSTRACT FROM AUTHOR]

Corrosion is a spontaneous process that can be slowed down, though not entirely prevented, through various methods. The most common method for protecting metals against corrosion involves the application of coatings, with nearly three-quarters of metal structures currently benefiting from organic coatings. In addition to providing effective corrosion protection, modern coatings are expected to be environmentally friendly. Presently, there is growing interest in researching coatings based on water-soluble natural polymers containing active chemical compounds, such as corrosion inhibitors. One such polymer is chitosan, which exhibits excellent film-forming ability in acidic aqueous solutions, making it well suited for diverse protective coating applications. This study explores the possibility of applying a chitosan-based coating with the addition of TiO2 and eucalyptol for the protection of steel against acid corrosion. The results confirmed that the tested chitosan-based coatings must incorporate an inhibitor to have a protective effect on the steel surface, since these coatings show a corrosive effect without an inhibitor. Although coatings based on chitosan and titanium dioxide with the addition of eucalyptol demonstrate protective effects, the duration of these effects is limited. Consequently, this method of protection could be suitable only for temporary protection of steel against acid corrosion. [ABSTRACT FROM AUTHOR]

Pharmaceuticals and personal care products (PPCPs) which include antibiotics such as tetracycline (TC) and ciprofloxacin (CIP), etc., have attracted increasing attention worldwide due to their potential threat to the aquatic environment and human health. In this work, a facile sol-gel method was developed to prepare tungsten-doped TiO2 with tunable W5+/W6+ ratio for the removal of PPCPs. The influence of solvents in the synthesis of the three different tungsten precursors doped TiO2 is also taken into account. WCl6, ammonium metatungstate (AMT), and Na2WO4●2H2O not only acted as the tungsten precursors but also controlled the tungsten ratio. The photocatalyst prepared by WCl6 as the tungsten precursor and ethanol as the solvent showed the highest photodegradation performance for ciprofloxacin (CIP) and tetracycline (TC), and the photodegradation performance for tetracycline (TC) was 2.3, 2.8, and 7.8 times that of AMT, Na2WO4●2H2O as the tungsten precursors and pristine TiO2, respectively. These results were attributed to the influence of the tungsten precursors and solvents on the W5+/W6+ ratio, sample crystallinity and surface properties. This study provides an effective method for the design of tungsten-doped TiO2 with tunable W5+/W6+ ratio, which has a profound impact on future studies in the field of photocatalytic degradation of PPCPs using an environmentally friendly approach. [ABSTRACT FROM AUTHOR]

The rapid expansion of industrial activities has resulted in severe environmental pollution manifested by organic dyes discharged from the food, textile, and leather industries, as well as hazardous gas emissions from various industrial processes. Titanium dioxide (TiO2)-nanostructured materials have emerged as promising candidates for effective photocatalytic dye degradation and gas sensing applications owing to their unique physicochemical properties. This study investigates the development of a photocatalyst and a liquefied petroleum gas (LPG) sensor using hydrothermally synthesized globosa-like TiO2 nanostructures (GTNs). The synthesized GTNs are then evaluated to photocatalytically degrade methylene blue dye, resulting in an outstanding photocatalytic activity of 91% degradation within 160 min under UV light irradiation. Furthermore, these nanostructures are utilized to sense liquefied petroleum gas, which attains a superior sensitivity of 7.3% with high response and recovery times and good reproducibility. This facile and cost-effective hydrothermal method of fabricating TiO2 nanostructures opens a new avenue in photocatalytic dye degradation and gas sensing applications. [ABSTRACT FROM AUTHOR]

The efficient adsorption and removal of As(III), which is highly toxic, remains difficult. TiO2 shows promise in this field, though the process needs improvement. Herein, how doping regulates As(OH)3 adsorption over TiO2 surfaces is comprehensively investigated by means of the DFT + D3 approach. Doping creates the bidentate mononuclear (Ce doping at the Ti5c site), tridentate (N, S doping at the O2c site), and other new adsorption structures. The extent of structural perturbation correlates with the atomic radius when doping the Ti site (Ce >> Fe, Mn, V >> B), while it correlates with the likelihood of forming more bonds when doping the O site (N > S > F). Doping the O2c, O3c rather than the Ti5c site is more effective in enhancing As(OH)3 adsorption and also causes more structural perturbation and diversity. Similar to the scenario of pristine surfaces, the bidentate binuclear complexes with two Ti-OAs bonds are often the most preferred, except for B doping at the Ti5c site, S doping at the O2c site, and B doping at the O3c site of rutile (110) and Ce, B doping at the Ti5c site, N, S doping at the O2c site, and N, S, B doping at the O3c site of anatase (101). Doping significantly regulates the As(OH)3 adsorption efficacy, and the adsorption energies reach −4.17, −4.13, and −4.67 eV for Mn doping at the Ti5c site and N doping at the O2c and O3c sites of rutile (110) and −1.99, −2.29, and −2.24 eV for Ce doping at the Ti5c site and N doping at the O2c and O3c sites of anatase (101), respectively. As(OH)3 adsorption and removal are crystal-dependent and become apparently more efficient for rutile vs. anatase, whether doped at the Ti5c, O2c, or O3c site. The auto-oxidation of As(III) occurs when the As centers interact directly with the TiO2 surface, and this occurs more frequently for rutile rather than anatase. The multidentate adsorption of As(OH)3 causes electron back-donation and As(V) re-reduction to As(IV). The regulatory effects of doping during As(III) adsorption and the critical roles played by crystal control are further unraveled at the molecular level. Significant insights are provided for As(III) pollution management via the adsorption and rational design of efficient scavengers. [ABSTRACT FROM AUTHOR]

The incorporation of titanium dioxide nanoparticles into concrete blocks for paving adds photocatalytic functionality to the cementitious matrix, providing self-cleaning and pollutant-degrading properties. However, wear and leaching from these pavements can release potentially toxic compounds into water bodies, affecting aquatic organisms. In this context, this study evaluated the toxicological effects of leachates from photocatalytic concrete containing nano-TiO2 with an average size of 10 nm and anatase crystallinity on Daphnia magna. Acute and chronic toxicity tests on neonates were conducted with two leachate extracts: one from reference concrete and one from photocatalytic concrete (with 9% nano-TiO2 added by mass of cement). In terms of acute toxicity, the reference concrete extract had an EC50 of 104.0 mL/L at 48 h, whereas the concrete with TiO2 had an EC50 of 64.6 mL/L at 48 h. For chronic toxicity, the leachate from reference concrete had a significant effect (p < 0.05) on the size parameter with an LOEC of 4 mL/L, whereas the leachate from concrete with 9% nano-TiO2 did not have significant toxicological effects on any of the analyzed parameters (longevity, size, reproduction, and age of first posture) (LOEC > 6.5 mL/L). Furthermore, FTIR analysis indicated that TiO2 nanoparticles were not detected in the leachates, suggesting efficient anchoring within the cementitious matrix. The results indicate that there was no increase in the chronic toxicity of the leachate from the cementitious matrix when nanoparticles were added at a 9% mass ratio of cement. [ABSTRACT FROM AUTHOR]

Titanium dioxide (TiO2) is a prevalent food additive, yet comprehensive data on particle size and dietary exposure are lacking in China. Transmission electron microscopy results revealed that the quantitative proportion of nanoparticles (NPs) in food-additive TiO2 was 37.7%, with a mass fraction of 9.89%. Laboratory test results showed that among the domestic products surveyed, candies excluding gum-based candies contained the highest content of TiO2. Using consumption data from the China Health and Nutrition Survey in 2018, the average dietary exposure for TiO2 and TiO2 NPs in the Chinese population were calculated at 34.84 and 3.44 μg/kg bw/day, respectively. The primary dietary sources were puffed food and powdered drinks. Exposure varied significantly across age and region, with children and Inner Mongolia residents having the highest intake. TiO2 NP exposure showed a negative correlation with age. Despite this, the dietary exposure risk of TiO2 NPs for the Chinese population remains deemed acceptable. [ABSTRACT FROM AUTHOR]

Recently, Pd catalysts supported on magnetic nanoparticles (MNPs) have attracted a great attention due to their ability of easy separation with an external magnet. Modification of MNPs is successfully used to obtain Pd magnetic catalysts with enhanced catalytic activity. In this work, we discussed the effect of titania content in TiO2/MNPs support materials on catalytic properties of Pd@TiO2/MNPs catalysts in phenylacetylene hydrogenation. TiO2/MNPs composites were prepared by simple ultrasound-assisted mixing of TiO2 and MNPs, synthesized by co-precipitation method. This was followed by deposition of palladium ions on the mixed metal oxides using NaOH as precipitant. The supports and catalysts were characterized using XRD, BET, STEM, EDX, XPS, and a SQUID magnetometer. Pd nanoparticles (5–6 nm) formed were found to be homogeneously distributed on support materials representing the well-mixed metal oxides with TiO2 content of 10, 30, 50, or 70%wt. Testing of the catalysts in phenylacetylene hydrogenation showed that their activity increased with increasing TiO2 content, and the process was faster in alkali medium (pH = 10). The hydrogenation rates of triple and double C–C bonds on Pd@70TiO2/MNPs achieved 9.3 × 10−6 mol/s and 23.1 × 10−6 mol/s, respectively, and selectivity to styrene was 96%. The catalyst can be easily recovered with an external magnet and reused for 12 runs without significant degradation in the catalytic activity. The improved catalytic properties of Pd@70TiO2/MNPs can be explained by the fact that the surface of the support is mainly composed of TiO2 particles, affecting the state and size of Pd species. [ABSTRACT FROM AUTHOR]

Titanium dioxide (TiO2) hollow nanoparticles present significant potential for photocatalytic applications while their straightforward preparation with precise structure control is still challenging. This work reports the approach to preparing tunable hollow TiO2 nanospheres by utilization of spherical polyelectrolyte brushes (SPB) as nanoreactors and templates. During the preparation, the evolution of the structure was characterized by small angle X-ray scattering (SAXS), and in combination with dynamic light scattering and transmission electron microscopy. The formation of TiO2 shell within the brush (SPB@TiO2) is confirmed by the significant increase of the electron density, and its internal structure has been analyzed by fitting SAXS data, which can be influenced by Titanium precursors and ammonia concentration. After calcining SPB@TiO2 in a muffle furnace, hollow TiO2 nanospheres are produced, and their transition to the anatase crystal form is triggered, as confirmed by X-ray diffraction analysis. Utilizing the advantages of their hollow structure, these TiO2 nanospheres exhibit exceptional catalytic degradation efficiency of methylene blue (MB), tetracycline (TC), and 2,4-dichlorophenoxyacetic acid (2,4-D), and also demonstrate excellent recyclability. [ABSTRACT FROM AUTHOR]

To investigate the carcinogenicity of anatase-type nano-titanium dioxide (aNTiO2), F344/DuCrlCrlj rats were exposed to aNTiO2 aerosol at concentrations of 0, 0.5, 2, and 8 mg/m³. The rats were divided into 2 groups: carcinogenicity study groups were exposed for two years, and satellite study groups were exposed for one year followed by recovery for 1 day, 26 weeks, and 52 weeks after the end of exposure. In the carcinogenicity groups, bronchiolo-alveolar carcinomas were observed in two 8 mg/m³-exposed males, showing an increasing trend by Peto's test. However, this incidence was at the upper limit of JBRC's historical control data. Bronchiolo-alveolar adenomas were observed in 1, 2, 3, and 4 rats of the 0, 0.5, 2, and 8 mg/m³-exposed females and were not statistically significant. However, the incidence in the 8 mg/m³-exposed females exceeded JBRC's historical control data. Therefore, we conclude there is equivocal evidence for the carcinogenicity of aNTiO2 in rats. No lung tumors were observed in the satellite groups. Particle-induced non-neoplastic lesions (alveolar epithelial hyperplasia and focal fibrosis) were observed in exposed males and females in both the carcinogenicity and satellite groups. Increased lung weight and neutrophils of bronchoalveolar lavage fluid were observed in the 8 mg/m³-exposed carcinogenicity groups. The aNTiO2 deposited in the lungs of the satellite group rats was decreased at 26 weeks after the end of exposure compared to 1 day after the end of exposure. At 52 weeks after the end of exposure, the decreased level was the same at 26 weeks after the end of exposure. [ABSTRACT FROM AUTHOR]

Automobile paint chips are a crucial piece of trace evidence for forensic investigators. This is because automotive paints are composed of multiple layers, including the primer, basecoat, and clearcoat, each of which has its own chemical composition that can vary by vehicle make, model, year, and manufacturing plant. Thus, Fourier‐transform infrared (FTIR) spectral databases for automobile paint systems have been established to aid law enforcement in, for example, narrowing search parameters for a suspect's vehicle. Recently, car manufacturers have implemented primers on plastic substrates that are much thinner (~5 μm) than those on metal substrates, making it more difficult to manually separate for analyses. Here, we evaluated FTIR microspectroscopy (μ‐FTIR) and optical photothermal infrared spectroscopy (O‐PTIR) to chemically image cross sections of paint chips without manually separating the layers. For μ‐FTIR, transmission and transflection modes provided the highest quality spectra compared to reflection and μ‐ATR analyses. Point analysis was preferable to chemical imaging, as peaks were identified in the point (MCT) detector's lower spectral range that was below the imaging (FPA) detector's cutoff, such as those associated with titanium dioxide. Reduced spectral range can lead to a similar issue in O‐PTIR analyses depending on instrument configuration. However, its complementary Raman spectra showed strong titanium dioxide peaks, providing an alternate means of identification. Both techniques are likely to become more relevant as they are non‐destructive and avoid manual separation of the layers. O‐PTIR is particularly well‐suited for analysis of the thin primer layer due to its superior spatial resolution. [ABSTRACT FROM AUTHOR]

• Composite photo–Fenton catalysts of N–doped TiO 2 and schwertmannite were prepared. • N–TiO 2 /SCH displayed a superior BPA degradation activity of ca. 100% within 60 min. • Hydroxyl radical and singlet oxygen are active species in this photo–Fenton system. Potential health risks related to environmental endocrine disruptors (EEDs) have aroused research hotspots at the forefront of water treatment technologies. Herein, nitrogen–doped titanium dioxide/schwertmannite nanocomposites (N–TiO 2 /SCH) have been successfully developed as heterogeneous catalysts for the degradation of typical EEDs via photo–Fenton processes. Due to the sustainable Fe(III)/Fe(II) conversion induced by photoelectrons, as–prepared N–TiO 2 /SCH nanocomposites exhibit much enhanced efficiency for the degradation of bisphenol A (BPA; ca. 100% within 60 min under visible irradiation) in a wide pH range of 3.0-7.8, which is significantly higher than that of the pristine schwertmannite (ca. 74.5%) or N–TiO 2 (ca. 10.8%). In this photo–Fenton system, the efficient degradation of BPA is mainly attributed to the oxidation by hydroxyl radical (•OH) and singlet oxygen (1O 2). Moreover, the possible catalytic mechanisms and reaction pathway of BPA degradation are systematically investigated based on analytical and photoelectrochemical analyses. This work not only provides a feasible means for the development of novel heterogeneous photo–Fenton catalysts, but also lays a theoretical foundation for the potential application of mineral–based materials in wastewater treatment. [ABSTRACT FROM AUTHOR]

Solar thermal storage ceramic materials use photothermal power generation technology to store heat energy, which is an important way to use clean energy and reduce carbon emissions. In this paper, MgAl2O4 ceramics were prepared by pressureless sintering with fused magnesia and α‐Al2O3 as the primary raw materials and TiO2 as the additive. The phase composition, microstructure, physical properties, thermal shock resistance, and thermal physical properties of MgAl2O4 thermal storage ceramics were studied. The results show that the main crystalline phase of B4 is MgAl2O4 and the secondary crystalline phase is MgTi2O5. Ti4+ is dissolved into MgAl2O4 lattice, which distorts the lattice, reduces activation energy, and promotes sintering. The sample B4 (69.73 wt% α‐Al2O3, 30.27 wt% fused magnesia, and 7 wt% TiO2) sintered at 1510°C had the best comprehensive physical properties, and its bending strength and bulk density were 89.41 MPa and 3.27 g/cm3, respectively. After 30 thermal shock cycles, the bending strength of the sample B4 is slightly lost. The thermal stress generated during the expansion and contraction of the grain volume led to the decrease of the bending strength. From room temperature to 1000°C, the specific heat capacity of sample B4 is.44–1.25 J/(g·K). The heat capacity increases with the increase of temperature, and the heat storage density increases. The heat storage density is 1218.75 kJ/kg (1000°C). Heat capacity increases with temperature due to intensified lattice vibration at high temperatures. Therefore, magnesia alumina spinel ceramics show great potential in solar thermal energy storage. [ABSTRACT FROM AUTHOR]