Search Results (558)

Uncooled microbolometers play a pivotal role in infrared detection owing to their compactness, low power consumption, and cost-effectiveness. This review comprehensively summarizes recent progress in thermistor materials and focal plane arrays (FPAs), highlighting improvements in sensitivity and integration. Vanadium oxide (VO_x) remains predominant, with Al-doped films via atomic layer deposition (ALD) achieving a temperature coefficient of resistance (TCR) of −4.2%/K and significant 1/f noise reduction when combined with single-walled carbon nanotubes (SWCNTs). Silicon-based materials, such as phosphorus-doped hydrogenated amorphous silicon (α-Si:H), exhibit a TCR exceeding −5%/K, while titanium oxide (TiO_x) attains TCR values up to −7.2%/K through ALD and annealing. Emerging materials including GeSn alloys and semiconducting SWCNT networks show promise, with SWCNTs achieving a TCR of −6.5%/K and noise equivalent power (NEP) as low as 1.2 mW/√Hz. Advances in FPA technology feature pixel pitches reduced to 6 μm enabled by vertical nanotube thermal isolation, alongside the 3D heterogeneous integration of single-crystalline Si-based materials with readout circuits, yielding improved fill factors and responsivity. State-of-the-art VO_x-based FPAs demonstrate noise equivalent temperature differences (NETD) below 30 mK and specific detectivity (D*) near 2 × 10¹⁰ cm⋅Hz ^1/2/W. Future advancements will leverage materials-driven innovation (e.g., GeSn/SWCNT composites) and process optimization (e.g., plasma-enhanced ALD) to enable ultra-high-resolution imaging in both civil and military applications. This review underscores the central role of material innovation and system optimization in propelling microbolometer technology toward ultra-high resolution, high sensitivity, high reliability, and broad applicability. Full article

This study investigates the synthesis and characterization of boron-modified nanotubular titania (NTO) arrays fabricated via a single-step anodizing process with varying concentrations of boric acid (BA). Following anodization, a reductive heat treatment was applied to facilitate the crystallization of the anatase phase in the boron-modified NTO. The effect of the BA concentration on the structural, morphological, and photoelectrochemical (PEC) properties of the NTOs was systematically explored through scanning electron microscopy (SEM), X-ray diffraction (XRD), X-ray photoelectron spectroscopy (XPS), luminescence, and UV-Vis spectrometry. The introduction of boron during anodization facilitated the formation of sub-bandgap states, thereby enhancing the light absorption and electron mobility. This study revealed the optimal BA concentration that yielded a 3.3-fold enhancement of the PEC performance, attributed to a reduction in the bandgap energy. Notably, the highest incident photon-to-current conversion efficiency (IPCE) was observed for NTO samples anodized at a 0.10 M BA concentration. These findings underscore the promise of boron-modified NTOs for advanced photocatalytic applications, particularly in solar-driven water-splitting processes. Full article

This study addresses the need for efficient photoelectric materials by fabricating Indium-doped tin sulfide (SnS-In)/titanium dioxide (TiO₂) heterostructure thin films via radio frequency (RF) magnetron sputtering. We systematically investigated the synergistic enhancement of photoelectric properties from both In-doping and the heterostructure design. SnS-In films with controlled In concentrations were prepared by embedding varying numbers of indium pellets into the SnS sputtering target. Our findings reveal that an optimal In doping of 4.93 at% significantly improves the crystalline quality and light absorption of SnS, reducing its band gap from 1.27 eV to 1.13 eV and enhancing carrier concentration and mobility. Subsequently, the optimized SnS-In film combined with TiO₂ formed a heterojunction, achieving a peak photocurrent density of 6.36 µA/cm² under visible light. This is 2.2 and 53.0 times higher than standalone SnS-In and TiO₂ films, respectively. This superior performance is attributed to the optimal In³⁺ doping effectively modulating the SnS band structure and the type-II heterojunction promoting efficient charge separation. This work demonstrates a promising strategy for optoelectronic conversion and photocatalysis by combining In-doping for SnS band structure engineering with TiO₂ heterostructure construction. Full article

Harnessing the synergistic potential of graphene oxide-doped titanium dioxide (GO-TiO₂), this study pioneers an advanced photocatalytic approach by incorporating graphene oxide-doped titanium dioxide (GO-TiO₂) as a catalyst to enhance the photocatalytic degradation of levofloxacin (LVX), with optimisation of parameters using response surface methodology (RSM) and artificial neural networks (ANNs). By adjusting key operational parameters such as catalyst dosage, LVX concentration, pH, and percentage dopant in TiO₂, the study aimed to maximise degradation efficiency. The RSM statistical model highlighted optimal conditions, i.e., neutral pH, 0.1 g/g dopant, 1.1 g/L catalyst, and 25 ppm LVX concentration, achieving a degradation efficiency close to 80% (R² = 0.88). An ANN model was also developed, offering a three-layer neural network that accurately predicts LVX degradation under varied conditions, with R² reaching 0.97. Current modelling techniques frequently fail to strike a balance between practical insights for optimising photocatalytic degradation and predictive accuracy. By combining the parametric insights of RSM with the nonlinear predictive power of ANN, this study closes that gap and develops a sustainable, data-driven framework for effectively breaking down pharmaceutical pollutants and developing environmentally friendly wastewater treatment methods. Full article

The problem of spreading harmful infections through contaminated surfaces has become more acute during the recent coronavirus pandemic. The design of self-cleaning materials, which can continuously decompose biological contaminants, is an urgent task for environmental protection and human health care. In this study, the surface of blended cotton/polyester fabric was functionalized with N-doped TiO₂ (TiO₂-N) nanoparticles using titanium(IV) isopropoxide as a binder to form durable photoactive coating and additionally decorated with Cu species to promote its self-cleaning properties. The photocatalytic ability of the material with photoactive coating was investigated in oxidation of acetone vapor, degradation of deoxyribonucleic acid (DNA) fragments of various lengths, and inactivation of PA136 bacteriophage virus and Candida albicans fungi under visible light and ultraviolet A (UVA) radiation. The kinetic aspects of inactivation and degradation processes were studied using the methods of infrared (IR) spectroscopy, polymerase chain reaction (PCR), double-layer plaque assay, and ten-fold dilution. The results of experiments showed that the textile fabric modified with TiO₂-N photocatalyst exhibited photoinduced self-cleaning properties and provided efficient degradation of all studied contaminants under exposure to both UVA and visible light. Additional modification of the material with Cu species substantially improved its self-cleaning properties, even in the absence of light. Full article

This study evaluates the efficiency of sub-stoichiometric Ti₄O₇ titanium oxide anodes for the electrochemical degradation of glyphosate, a persistent herbicide classified as a probable carcinogen by the World Health Organization. After optimizing the process operating parameters (pH and current density), the mineralization efficiency and fate of degradation by-products of the treated solution were determined using a total organic carbon (TOC) analyzer and HPLC/MS, respectively. The results showed that at pH = 3, glyphosate degradation and mineralization are enhanced by the increased generation of hydroxyl radicals (^●OH) at the anode surface. A current density of 14 ${\mathrm{mA} \mathrm{cm}}^{-2}$ enables complete glyphosate removal with 77.8% mineralization. Compared with boron-doped diamond (BDD), ${\mathrm{Ti}}_4{\mathrm{O}}_7$ shows close performance for treatment of a concentrated glyphosate solution (0.41 mM), obtained after nanofiltration of a synthetic ionic solution (0.1 mM glyphosate), carried out using an NF-270 membrane at a conversion rate (Y) of 80%. At 10${ \mathrm{mA} \mathrm{cm}}^{-2}$ for 8 h, ${\mathrm{Ti}}_4{\mathrm{O}}_7$ achieved 81.3% mineralization with an energy consumption of 6.09 ${\mathrm{kWh} \mathrm{g}}^{-1}$ TOC, compared with 90.5% for BDD at 5.48 ${\mathrm{kWh} \mathrm{g}}^{-1}$ TOC. Despite a slight yield gap, ${\mathrm{Ti}}_4{\mathrm{O}}_7$ demonstrates notable efficiency under demanding conditions, suggesting its potential as a cost-effective alternative to BDD for glyphosate electro-oxidation. Full article

Hydrogen (H₂) gas sensors are essential for detecting leaks and ensuring safety, thereby supporting the broader adoption of hydrogen energy. The performance of H₂ sensors has been shown to be improved by the incorporation of TiO₂ nanostructures. The key findings are summarized as follows: (1) Resistive random-access memory (ReRAM) technology was used to fabricate extremely compact H₂ sensors via various forming techniques, and substantial sensor performance enhancement was investigated. (2) A nanocontact composed of titanium oxide (TiO_x)/platinum (Pt) was subjected to various forming operations to establish a Schottky junction with a nanogap structure on a tantalum oxide (Ta₂O₅) layer, and its properties were assessed. (3) When the Pt electrode was on the positive side during the forming operation used for ReRAM technology, a Pt nanopillar structure was produced. By contrast, when the forming operation was conducted with a positive bias on the TiO_x side, a mixed oxide film of Ta and Ti was produced, which indicates local Ta doping into the TiO_x. A sensor response of over 1000 times was achieved at a minimal voltage of 1 mV at room temperature. (4) This sensor fabrication technology based on the forming operation is promising for the development of low-power consumption sensors. Full article

In this study, lanthanum–nitrogen co-doped titanium dioxide (La-N-TiO₂) thin films were fabricated using Ion Beam Assisted Deposition (IBAD) and subjected to accelerated ultraviolet (UV) aging experiments to systematically investigate the impact of co-doping on the films’ resistance to UV aging. X-ray diffraction (XRD) analysis revealed that La-N co-doping inhibits the phase transition from anatase to rutile, significantly enhancing the phase stability of the films. Scanning electron microscopy (SEM) and atomic force microscopy (AFM) characterizations indicated that co-doping increased the density and surface uniformity of the films, thereby delaying the expansion of cracks and increase in roughness induced by UV exposure. Energy-dispersive X-ray spectroscopy (EDS) results confirmed the successful incorporation of La and N into the TiO₂ lattice, enhancing the chemical stability of the films. Contact angle tests demonstrated that La-N co-doping markedly improved the hydrophobicity of the films, inhibiting the rapid decay of hydrophilicity during UV aging. After three years of UV aging, the co-doped films maintained high structural integrity and photocatalytic performance, exhibiting excellent resistance to UV aging. These findings offer new insights into the long-term stability of photovoltaic self-cleaning materials. Full article

To improve implant osseointegration while preventing infection, we developed a strontium (Sr)-doped Ti₃C₂T_x MXene coating on titanium, aiming to synergistically enhance bone integration and antibacterial performance. MXene is a family of two-dimensional transition-metal carbides/nitrides whose abundant surface terminations endow high hydrophilicity and bioactivity. The coating was fabricated via anodic electrophoretic deposition (40 V, 2 min) of Ti₃C₂T_x nanosheets, followed by SrCl₂ immersion to incorporate Sr²⁺. The coating morphology, phase composition, chemistry, hydrophilicity, mechanical stability, and Sr²⁺ release were characterized. In vitro bioactivity was assessed with rat bone marrow mesenchymal stem cells (BMSCs)—with respect to viability, proliferation, migration, alkaline phosphatase (ALP) staining, and Alizarin Red S mineralization—while the antibacterial efficacy was evaluated against Staphylococcus aureus (S. aureus) via live/dead staining, colony-forming-unit enumeration, and AlamarBlue assays. The Sr-doped MXene coating formed a uniform lamellar structure, lowered the water-contact angle to ~69°, and sustained Sr²⁺ release (0.36–1.37 ppm). Compared to undoped MXene, MXene/Sr enhanced BMSC proliferation on day 5, migration by 51%, ALP activity and mineralization by 47%, and reduced S. aureus viability by 49% within 24 h. Greater BMSCs activity accelerates early bone integration, whereas rapid bacterial suppression mitigates peri-implant infection—two critical requirements for implant success. Sr-doped Ti₃C₂T_x MXene thus offers a simple, dual-function surface-engineering strategy for dental and orthopedic implants. Full article

Background/Objectives:Titanium implant surface modifications enhance osseointegration and prevent microbial colonization, improving implant longevity. Antimicrobial coatings, particularly cerium- and bismuth-doped hydroxyapatite (CeHAp and BiHAp), have gained attention for reducing infection-related complications. This study evaluates the antimicrobial activity of CeHAp and BiHAp coatings on CpTi compared to untreated CpTi in artificial saliva at pH levels of 4.5, 6.5, and 8. Methods: Antibacterial efficacy against Staphylococcus aureus (S. aureus), Escherichia coli (E. coli), and Candida albicans (C. albicans) was assessed using the broth dilution method. Titanium rods coated with test compounds were incubated in inoculated nutrient broth, and microbial inhibition was determined via optical density at 600 nm. A statistical analysis was performed using the Kruskal–Wallis ANOVA test, the median and Interquartile Range were determined for the variables, and a Dwass–Steel–Critchlow–Fligner intergroup pairwise comparison was conducted. Results: The results showed that both the CeHAp and BiHAp coatings demonstrated significant antimicrobial activity against S. aureus (OD = 0.01) at pH 6.5, which was more pronounced than the activity observed against E. coli (OD = 0.05), with the difference being statistically significant (p = 0.001). The least antimicrobial activity was observed against C. albicans (0.21) at pH 8 (p = 0.001). Conclusion: These findings highlight the pH-dependent effectiveness of BiHAp and CeHAp coatings in inhibiting microbial growth. Their application on titanium implants may enhance antimicrobial properties, contributing to improved dental implant success and broader biomedical applications. Full article

In the environment, plastic waste degrades into small particles known as microplastics and nanoplastics (MNPLs), depending on their size. Given the potential harmful effects associated with MNPL exposure, it is crucial to develop environmentally representative particles for hazard assessment. These so-called true-to-life MNPLs are generated through in-house degradation of real-world plastic products. In this study, we produced titanium-doped nanoplastics (NPLs) from opaque polyethylene terephthalate (PET) milk bottles, which contain titanium dioxide as a filler. The resulting PET(Ti)-NPLs were thoroughly characterized using scanning electron microscopy (SEM), energy-dispersive X-ray spectroscopy (EDS), mass spectrometry (MS), dynamic light scattering (DLS), ζ-potential measurements, transmission electron microscopy (TEM), and Fourier-transform infrared (FTIR) spectroscopy. Human-derived THP-1 monocytes were employed to investigate particle uptake kinetics, dosimetry, and genotoxicity. A combination of flow cytometry and inductively coupled plasma mass spectrometry (ICP-MS) enabled the quantification of internalized particles, while the comet assay assessed DNA damage. The results revealed dose- and time-dependent effects of PET(Ti)-NPLs on THP-1 cells, particularly in terms of internalization. Titanium doping facilitated detection and influenced genotoxic outcomes. This study demonstrates the relevance of using environmentally representative nanoplastic models for evaluating human health risks and underscores the importance of further mechanistic research. Full article

Titanium dioxide (TiO₂) is a wide-bandgap semiconductor material with broad application potential, known for its excellent photocatalytic performance, high chemical stability, low cost, and non-toxicity. These properties make it highly attractive for applications in photovoltaic energy, environmental remediation, and optoelectronic devices. For instance, TiO₂ is widely used as a photocatalyst for hydrogen production via water splitting and for degrading organic pollutants, thanks to its efficient photo-generated electron–hole separation. Additionally, TiO₂ exhibits remarkable performance in dye-sensitized solar cells and photodetectors, providing critical support for advancements in green energy and photoelectric conversion technologies. Boron-doped diamond (BDD) is renowned for its exceptional electrical conductivity, high hardness, wide electrochemical window, and outstanding chemical inertness. These unique characteristics enable its extensive use in fields such as electrochemical analysis, electrocatalysis, sensors, and biomedicine. For example, BDD electrodes exhibit high sensitivity and stability in detecting trace chemicals and pollutants, while also demonstrating excellent performance in electrocatalytic water splitting and industrial wastewater treatment. Its chemical stability and biocompatibility make it an ideal material for biosensors and implantable devices. Research indicates that the combination of TiO₂ nanostructures and BDD into heterostructures can exhibit unexpected optical and electrical performance and transport behavior, opening up new possibilities for photoluminescence and rectifier diode devices. However, applications based on this heterostructure still face challenges, particularly in terms of photodetector, photoelectric emitter, optical modulator, and optical fiber devices under high-temperature conditions. This article explores the potential and prospects of their combined heterostructures in the field of optoelectronic devices such as photodetector, light emitting diode (LED), memory, field effect transistor (FET) and sensing. TiO₂/BDD heterojunction can enhance photoresponsivity and extend the spectral detection range which enables stability in high-temperature and harsh environments due to BDD’s thermal conductivity. This article proposes future research directions and prospects to facilitate the development of TiO₂ nanostructured materials and BDD-based heterostructures, providing a foundation for enhancing photoresponsivity and extending the spectral detection range enables stability in high-temperature and high-frequency optoelectronic devices field. Further research and exploration of optoelectronic devices based on TiO₂-BDD heterostructures hold significant importance, offering new breakthroughs and innovations for the future development of optoelectronic technology. Full article

Electrocatalytic urea synthesis offers great potential for sustainable strategies through CO₂ and NO₃⁻ reduction reactions. However, the development of high-performance catalysts is often hampered by the complexity of synthetic methodologies and the unresolved nature of C-N coupling pathways. In this study, we present a copper–indium co-doped titanium dioxide (CuIn-TiO₂) catalyst that exhibits remarkable efficacy in enhancing the synergistic reduction of CO₂ and NO₃⁻ to produce urea. The bimetallic CuIn site functions as the primary active site for the C-N coupling reaction, achieving a urea yield rate of 411.8 μg h⁻¹ mg_cat⁻¹ with a Faradaic efficiency of 6.7% at −0.8 V versus reversible hydrogen electrode (vs. RHE). A body of experimental and theoretical research has demonstrated that the nanoscale particles enhance the density of active sites and improve the feasibility of reactions on the surface of TiO₂. The co-doping of Cu and In has been shown to significantly enhance electronic conductivity, increase the adsorption affinity for *CO₂ and *NO₃⁻, and promote the C-N coupling process. The CuIn-TiO₂ catalyst has been demonstrated to effectively promote the reduction of NO₃⁻ and CO₂, as well as accelerate the C-N coupling reaction. This effect is a result of a synergistic interaction among the catalyst’s components. Full article

Titanium dioxide (TiO₂) has been widely used as a potential candidate for the production of green hydrogen using the artificial photosynthesis approach. However, the wide bandgap (∼3.3 eV) of anatase TiO₂ makes it difficult to absorb a large fraction of the solar radiation reaching the Earth, thus providing a low photocatalytic activity. Anatase TiO₂ absorbs only 4% of solar radiation, which can be improved by engineering its bandgap to enhance absorption in the visible region. In the literature, many strategies have been adopted to improve the photocatalytic activity of TiO₂, such as metal and non-metal doping and heterojunctions. These techniques have shown incredible enhancement in visible light absorption and improved photocatalytic activity due to their ability to lower the bandgap of pure TiO₂ semiconductors. This review highlights different techniques like doping, heterojunctions, acidic modification, creating oxygen vacancies, and temperature- and pressure-dependence, which have improved the photochemical response of TiO₂ by improving charge-transfer efficiencies. Additionally, the charge-transfer mechanism and enhancement in the photochemical response of TiO₂ is discussed in each portion separately. Full article

To address the biological inertness of pure titanium implants, a composite coating with a strontium-doped hydroxyapatite (Sr-HA) phase and H₂Ti₅O₁₁·H₂O nanorods was engineered via ultrasonic-assisted micro-arc oxidation (UMAO) with hydrothermal treatment (HT). The ultrasonic field was applied to modulate the MAO discharge behavior, enhancing ion transport and coating formation. Structural characterization revealed that UMAO-HT coatings exhibited a lower anatase/rutile ratio and higher Sr-HA crystallinity, as compared to MAO-HT. In vitro simulated body immersion studies showed that UMAO-HT induced rapid apatite formation within 24 h, with a better apatite-inducing ability than the conventional MAO-HT. Density functional theory (DFT) simulations demonstrated that Sr substitution in HA lowered the (001) surface work function, enhancing Ca²⁺ adsorption energy and promoting apatite phase nucleation. This work reported the synergistic effects of ultrasonic-induced microstructure optimization and Sr-HA higher bioactivity, providing a mechanistic framework for designing next-generation bioactive coatings with enhanced osseointegration potential. Full article