Search Results (483)

Metal oxide thin-film transistors (MO TFTs) have drawn wide interest in photodetectors and optoelectronic synaptic devices owing to their wide bandgap, low off-state current, high optical transparency, low-temperature processing, and large-area uniformity. Gate modulation in the TFT structure can tune the channel’s initial state and interfacial electric field, enhancing the tunability of photogenerated carrier transport, defect trapping/release, and interfacial charge regulation. This article reviews the progress of MO TFT photodetectors and optoelectronic synaptic devices, and examines the roles of light absorption, carrier transport, defect-related carrier dynamics, interfacial charge control, and persistent photoconductivity in different device functions. For photodetectors, key goals include broadening the response spectrum, reducing dark current, improving spectral selectivity, and enhancing response stability. For optoelectronic synaptic devices, post-illumination conductance retention and slow relaxation enable memory retention and synaptic weight modulation. Thus, rather than being separate, photodetection and optoelectronic synapses are functional extensions of the MO TFT optoelectronic response under different application targets. This article further discusses the synergy between these two functions in array sensing, visual preprocessing, and intelligent vision systems. Future development requires advances in targeted defect engineering, interface and structure optimization, array uniformity, standardized evaluation, and device–circuit–algorithm co-design for low-power, integrable intelligent vision hardware. Full article

This study examines the effect of graphene oxide nanoparticle (NGO) doping (0.12–0.24 mol%) on the properties of FTO layers obtained by spray pyrolysis. The results show that nanographene promotes phase separation within the FTO bulk. The resulting inhomogeneities are fluorine-depleted relative to the surrounding film. NGO doping also modifies the position and intensity of peaks in the absorption spectra, indicating a change in the nature of the absorbing centers. The optical bandgap of the FTO layers decreases with the increase in NGO from 4.4 eV (undoped samples) to 3.95 eV (samples with the highest NGO concentration). Furthermore, NGO doping reduces the sheet resistance of the FTO layers. This reduction is attributed to increased charge carrier mobility resulting from passivation of nanocrystallite interfaces by graphene oxide nanoparticles. However, the sheet resistance depends non-monotonically on NGO content, with the lowest value observed at 0.16 mol% NGO. The increase in resistance at higher NGO concentrations is due to enhanced carrier scattering caused by the growing size and number of the phase inhomogeneities within the FTO layer. Full article

Low-emissivity (low-E) coatings are among the most effective thin-film technologies for reducing radiative heat losses and controlling solar heat gain in buildings, which account for approximately 30–40% of global primary energy consumption. This expanded review follows the technological evolution of low-E glazing from early transparent-conductor “heat mirrors” to modern multi-silver dielectric/metal/dielectric (D/M/D) architectures and emerging functional coatings. Four complementary perspectives are addressed: (i) the materials employed, from silver-based multilayers and transparent conducting oxides (ITO, FTO, AZO, GZO) to seed, blocker, and protective dielectric layers; (ii) the deposition systems, contrasting on-line pyrolytic/CVD “hard” coatings with off-line magnetron-sputtered “soft” coatings, together with ALD, sol–gel, and evaporation routes; (iii) the methods of analysis used to correlate microstructure, composition. and interfaces with optical, electrical, and thermal behaviour (XRD, XRR, SEM/TEM, AFM, XPS, SIMS, spectrophotometry, ellipsometry, emissivity, and U-value metrology according to EN 410/EN 673 and ISO 9050); and (iv) the functional performance of low-E stacks in insulating glass units, vacuum glazing, retrofit films, and smart-window systems across climate zones. Persistent research gaps are identified in long-term durability and ageing, indium-free scalable materials, standardized accelerated testing, and multi-objective design of thinner, more selective, and more robust stacks. Full article

Transparent conducting oxides and electron transport layers are central to optoelectronic devices, yet their interfacial electronic behavior remains strongly dependent on substrate chemistry, defect states, and surface potential alignment. Here, we compare ITO and FTO transparent electrodes coated with ZnO and TiO₂, combining ab initio simulations, surface potential mapping, Hall effect measurements, sheet resistance, microscopy, and optical spectroscopy. Density functional calculations show that both ITO and FTO behave as degenerately doped n-type transparent conducting oxides, but with distinct work functions, surface dipoles, and donor-state distributions, leading to different interfacial charge-transfer tendencies. ZnO- and TiO₂-coated substrates display markedly different temperature-dependent transport, including resistance hysteresis and carrier-type switching, with FTO-based heterojunctions showing more clearly defined transitions due to the greater thermal stability of FTO. Scanning Kelvin probe (SKP) measurements reveal that ZnO more effectively accepts electrons from ITO or FTO, whereas TiO₂ shows weaker electron accumulation and more resistive interfacial behavior. Optical measurements and HSE06-based simulations confirm that TiO₂ behaves as a wider-gap ultraviolet absorber, while ZnO exhibits a lower-energy absorption onset, with real spectra additionally shaped by substrate, thickness, scattering, and defect contributions. The results show that transparent conducting oxide substrates are active electronic participants, not passive supports, in ZnO- and TiO₂-based optoelectronic interfaces. Full article

Graphene oxide (GO) and reduced graphene oxide (rGO) are widely studied two-dimensional carbon nanomaterials for optoelectronic devices. Because the oxygen content and degree of reduction govern the electronic structure of GO-derived films, controlling the reduction process is essential for tailoring their properties. Laser-induced reduction provides a tunable, contact-free route to transparent and conductive graphene-based layers. In this work, 80 nm spray-coated GO layers were reduced using a KrF excimer laser (248 nm, 20 ns) at a fluence of 20 mJ cm⁻², while systematically varying the number of laser pulses (LP) from 1 to 1000. We tuned the degree of GO reduction by stepwise increasing the number of LP and followed the resulting changes in surface composition using X-ray photoelectron spectroscopy (XPS) and near-edge X-ray absorption fine-structure (NEXAFS) spectroscopy. The surface composition evolves non-monotonically with the number of laser pulses, revealing a multi-step reduction mechanism. At low laser doses, epoxide groups are preferentially removed or converted, generating a more disordered distribution of hydroxyl-containing sites on the GO sheets. At intermediate laser doses, oxygen-containing groups are depleted, and sp² conjugation is restored. After extended irradiation in air, however, oxygenated surface species partially re-form. Conductivity measurements show that the sheet resistance reaches a minimum at approximately 300 LP, consistent with efficient chemical reduction and recovery of the conjugated carbon network. These results provide molecular-level guidelines for optimizing laser-induced GO reduction toward graphene-based transparent conductive layers. Full article

In the present work, graphene-modified zinc oxide (ZnO-rGO) and fluorine-doped tin oxide (FTO) thin films were successfully fabricated using a simple, low-cost pulsed spray pyrolysis technique. The structural, morphological, optical, electrical, and surface electronic properties of the deposited films were systematically characterized. X-ray diffraction (XRD) analysis confirmed the formation of polycrystalline ZnO- and SnO₂-based phases with crystallite sizes in the nanometer range. The crystallographic parameters, microstrain, and dislocation density of the deposited films were found to be influenced by the incorporation of reduced graphene oxide (rGO) and fluorine dopants. Scanning electron microscopy (SEM) revealed compact and homogeneous surface morphologies with good film coverage and well-defined nanocrystalline features. Optical characterization demonstrated the wide-bandgap semiconducting behavior of the deposited films, with optical bandgap energies ranging from 3.262 to 3.312 eV for the ZnO-rGO films and from 3.91 to 4.01 eV for the FTO films. Kelvin probe measurements yielded work-function values in the range of approximately 5.0–5.2 eV, indicating favorable surface electronic characteristics suitable for optoelectronic applications. Furthermore, fluorine incorporation enhanced the dielectric response of the SnO₂ films, particularly in the low-frequency region owing to increased interfacial polarization effects. The obtained results demonstrate that pulsed spray pyrolysis provides a simple, cost-effective, and efficient route for fabricating ZnO-rGO and FTO thin films with desirable structural, optical, electrical, and surface electronic properties. These findings highlight the considerable potential of the developed materials for transparent electrodes and a wide range of optoelectronic applications. Full article

Spray pyrolysis is a popular method for the low-cost synthesis of oxides and other compounds in thin-film form. Here, we discuss several nuances of using this method for ternary and quaternary compounds. Specifically, we outline how precursor solubility and thermal decomposition, as well as desorption of intermediate species from the sample surface govern the spray pyrolysis growth process. We demonstrate how the stoichiometry transfer from solution to film can be affected in selected test cases. We present real-time optical growth measurements of the behaviour of individual Cu, Cr, Zn, and Sn precursors, as well as post-growth analysis of film composition by X-ray photoelectron spectroscopy for ternary transparent conducting oxides (TCOs; p-type: Cu_xCrO₂, SnTiO_x; and n-type: a-ZnSnO₃). We illustrate how several steps of spray pyrolysis affect the stoichiometry transfer from the solution to the ternary thin film. Using binary Cu₂O as a test case, we also show how the choice of instrument geometry and nozzle type can affect film homogeneity. All materials discussed have been chosen to highlight potential difficulties of the spray pyrolysis process of ternary, quaternary, or even more complex oxides, and the mechanisms should be considered for other materials as well. We therefore also provide an extensive overview of suitable precursor salts with similar expected properties as used in this experimental work to guide future ternary oxide studies. Full article

Transparent conductive oxides (TCOs) are indispensable core materials for optoelectronic devices, yet the inherent conflict between electrical conductivity and optical transparency, along with the scarcity and brittleness of indium tin oxide (ITO), severely limits their sustainable development. This review systematically summarizes the research progress of next-generation TCOs, focusing on microstructural engineering, advanced doping strategies, and architectural innovation to decouple the conductivity–transparency trade-off. The fundamental mechanisms of carrier scattering (ionized impurity scattering, grain boundary scattering) and the mobility-centric design paradigm are elaborated. The research status of typical material systems (SnO₂-based, ZnO-based, In₂O₃-based) is analyzed, and the mechanisms of high-valent cation doping, interstitial doping, and critical nucleation in optimizing carrier mobility are clarified. The oxide/metal/oxide (OMO) multilayer architecture is highlighted as a breakthrough strategy for synergistic optoelectronic performance. Current challenges including thermal stability, large-area fabrication, and environmental reliability are discussed, and future directions such as resonant doping, machine learning-assisted optimization, and multifunctional integration are prospected. This work provides a systematic theoretical basis and technical reference for the development of high-performance, sustainable TCOs. Full article

Background/Objectives: Metabolic dysfunction-associated steatotic liver disease (MASLD), a leading cause of chronic liver disease, encompasses a continuum from steatosis to metabolic dysfunction-associated steatohepatitis (MASH), fibrosis, cirrhosis, and hepatocellular carcinoma. This review aimed to synthesize current evidence on how metabolomic, lipidomic, and spatial multi-omic approaches illuminate MASLD pathogenesis and support precision hepatology. Methods: A structured narrative review was conducted through searches of PubMed, Scopus, and Web of Science, complemented by manual screening of key references. Studies were prioritized when they addressed MASLD biology, metabolic rewiring, lipid remodeling, mitochondrial dysfunction, inflammatory and fibrogenic pathways, gut–liver–adipose crosstalk, biomarker development, or therapeutic monitoring. Results: The reviewed evidence identifies MASLD as a systemic metabolic disorder shaped by excess lipid flux, enhanced de novo lipogenesis, impaired mitochondrial adaptation, oxidative and endoplasmic reticulum stress, sterile inflammation, and hepatic stellate-cell activation. Recurrent metabolomic signatures include altered amino acid, fatty acids, bile acid, and microbial co-metabolite pathways. Lipidomic studies consistently implicate depletion of protective polyunsaturated fatty acids, lysophosphatidylcholines, and phosphatidylcholines, in association with accumulation of diacylglycerols and ceramides, in the transition from steatosis to MASH and fibrosis. Emerging spatial and multi-omic analyses further resolve cell-specific metabolic niches involving hepatocytes, macrophages, endothelial cells, and stellate cells. Conclusions: Metabolomics provides a mechanistic and translational bridge between molecular injury, histological progression, and non-invasive risk stratification in MASLD. Future progress requires standardized analytical workflows, longitudinal validation, causal pathway interrogation, and integration with imaging, genetics, microbiome profiling, and treatment-response phenotyping. Clinical implementation will require standardized platforms, transparent metabolite identification, external validation across diverse populations, cost-effectiveness analyses, and regulatory-grade evidence of clinical utility. Full article

Silver nanowires (Ag NWs) are of great importance for modern applications as a substitute for indium tin oxide (ITO) when flexible, transparent conductive electrodes are required. In this paper, we report for the first time the electrical resistivity (ρ) of an isolated Ag nanowire not supported on a substrate, measured using transmission electron microscopy (TEM). Our results show a resistivity value on the order of 10⁻⁷ Ω-m, which is significantly higher than that of the bulk silver, which is 1.59 × 10⁻⁸ Ω-m. We attribute the reduction in electrical conductivity to three main factors: (i) surface scattering, (ii) internal boundaries, and (iii) internal stress. The electrical conductivity of Ag/Ni nanowires was also evaluated. The deposition of Ni layers onto Ag NWs forms a core–shell structure, resulting in a slight decrease in resistance comparable to Ag nanowires. This indicates that electrical transport is mainly governed by the highly conductive Ag core, whereas the Ni shell plays an indirect role through structural stabilization and modulation of surface states and scattering mechanisms, rather than directly enhancing intrinsic conductivity. Full article

In the present paper, we studied the interaction of microwave radiation with conductive indium tin oxide (ITO) coatings deposited on a borosilicate glass. The experiments were carried out with the ITO films, the thickness of which varied in the range from 85 to 607 nm. The transmittance and reflectivity of the ITO film/K108 glass structures were measured in the frequency region from 3 to 23 GHz. Theoretical modeling of the spectra was performed by means of the transfer matrix method. It was shown that for a given thickness of the glass substrate, the transmission and reflection spectra of the ITO film/K108 glass structures were fully determined by only one parameter of the ITO film, namely, its DC sheet resistivity. The considered model predicts an increase in maximum microwave shielding effectiveness up to 45.6 dB with a decrease in DC sheet resistivity to 1 Ohm/sq. ITO coatings with DC sheet resistivities down to 2.3 Ohm/sq have been experimentally investigated. The model microwave transmittance and reflectivity spectra were in good agreement with the experimental ones. In particular, the coefficient of determination for the transmittance spectra was rather high: R² > 0.93. It was experimentally demonstrated that applying antireflective coatings on both sides of the ITO film/K108 glass microwave shielding filter significantly improved its transparency in the operating optical range. A filter has been created that provides microwave shielding effectiveness of 38.7 dB with an average transmission coefficient of 0.81 in the visible range. Full article

Strenuous exercise is a well-established physiological stimulus that enhances muscular strength and hypertrophy but can also increase reactive oxygen species production, leading to oxidative stress (OS). Numerous studies have investigated whether dietary supplements can attenuate exercise-induced OS, yet findings remain inconsistent, and methodological quality varies. This systematic review aimed to synthesize current clinical evidence on dietary supplementation for OS management in young adults undergoing intensive exercise and to evaluate study methodology critically. The review was conducted in accordance with PRISMA 2021 guidelines and the Cochrane Risk of Bias (RoB 2.0) framework and was prospectively registered in PROSPERO. A comprehensive search of MEDLINE (PubMed), Scopus, Cochrane Central, ClinicalTrials.gov, OpenGrey, and ISRCTN identified interventional and observational human studies assessing supplementation and OS biomarkers. Forty-six studies met the inclusion criteria. The analysis revealed substantial heterogeneity in study design and reporting quality. Frequent methodological limitations included incomplete reporting of allocation concealment, participant and investigator blinding, examiner involvement, and deviations from intended interventions. Despite these limitations, several studies reported favorable effects of specific supplements on OS modulation and post-exercise recovery. Overall, the findings highlight widespread methodological shortcomings and emphasize the need for standardized trial designs, consistent biomarker selection, and transparent reporting. Well-designed, long-term randomized controlled trials are required to establish robust, evidence-based guidelines for dietary supplement use in managing exercise-induced OS in young adults. Full article

Copper (Cu) thin films and meshes on polyethylene terephthalate (PET) substrates are promising flexible transparent conductive electrodes (TCEs), yet their practical use is limited by insufficient interfacial adhesion and poor oxidative stability on inert polymer substrates. This work addresses these issues via a synergistic strategy of interfacial layer engineering and maskless laser lithography-based aperiodic mesh patterning, systematically comparing ceramic (Al₂O₃) and metallic (NiCr) interfacial layers for PET-supported Cu films and fabricating Linear/Sinusoidal aperiodic Cu meshes with tailored performance. Magnetron sputtering shows that Ar plasma-activated NiCr interfacial layers form a gradient-alloyed interface with Cu via interdiffusion, achieving 5B-level adhesion, mitigating bending-induced stress concentration, and enhancing damp-heat resistance (85 °C/85% RH) by suppressing oxidation—outperforming brittle Al₂O₃ layers. Patterning the optimized Cu/NiCr/PET structure into micrometer-scale meshes yields a Linear design with superior optoelectronic performance (~10.8 Ω/sq sheet resistance, >87% transmittance at 550 nm) and a Sinusoidal design with enhanced bending robustness via stress delocalization. Microstructural and elemental analyses clarify the NiCr layer’s interfacial toughening and anti-oxidation mechanisms. Practical validation in flexible transparent heaters demonstrates rapid thermal response and >20 h continuous operational stability. This study provides a scalable design strategy for high-performance PET-supported Cu meshes, offering insights for interface and structural optimization of flexible metallic TCEs for next-generation optoelectronics. Full article

Magnesium alloys offer low density, high strength, excellent heat dissipation, and good electrical conductivity, benefiting automotive and aerospace sectors. However, magnesium and its alloys are highly susceptible to corrosion, which severely limits their practical use. In this study, the hydrothermal deposition of graphene oxide (GO) and layered double hydroxides (LDHs) was achieved on the surface of an anodized magnesium alloy, forming a GO/LDH coating. The effects of pH and various anionic corrosion inhibitors on the corrosion resistance of the GO/LDH coating were subsequently investigated. The results show that the GO/LDH coating prepared at pH 10.8 exhibits the best corrosion resistance, which is generally associated with a greater coating thickness, with its nanosheets growing in a wavy manner in all directions. This coating also shows higher crystal transparency and a denser layered structure. Based on this, anionic corrosion inhibitors including molybdate, vanadate, and tungstate were incorporated into the GO/LDH coating. Electrochemical impedance (EIS) analysis subsequently revealed that the GO/LDH–molybdate coating exhibited the highest |Z|_{0.01 HZ}, reaching ~10^5.5 Ω cm², indicating its excellent corrosion resistance. This approach offers a novel and effective route to significantly improve the corrosion resistance of magnesium alloys via synergistic coating design. Full article

Flexible transparent conductive films (TCFs) and their applications have attracted extensive interest. Silver nanowires (AgNWs) have been explored to replace conventional indium tin oxide (ITO) due to their high optical transmittance and superior electrical conductivity. Nevertheless, AgNWs tend to oxidize under ambient conditions, which weakens the conductive network and limits long-term performance. Spraying reduced graphene oxide (rGO) can stabilize the conductive network and inhibit oxidation, thereby enhancing the overall properties of the films. In this work, rGO/AgNW/PET TCFs were prepared using a spray-coating approach. The transmittance of the rGO/AgNW/PET TCFs was measured at 77% at 550 nm, accompanied by a sheet resistance of 6.8 Ω/sq. The films achieved the surface temperature of 95 °C at 6 V with stable operation while also achieving an electromagnetic interference shielding effectiveness of 27 dB. This structural design improves both performance and stability, offering great potential for flexible TCFs in advanced optoelectronic applications. Full article