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Plasma etching processes for multi-atomic oxide thin films have become increasingly important owing to the excellent material properties of such thin films, which can potentially be employed in next-generation displays. To fabricate high-performance and reproducible devices, the etching mechanism and surface properties must be understood. In this study, we investigated the etching characteristics and changes in the surface properties of InGaZnO4 (IGZO) thin films with the addition of O2 gases based on a CF4/Ar high-density-plasma system. A maximum etch rate of 32.7 nm/min for an IGZO thin film was achieved at an O2/CF4/Ar (=20:25:75 sccm) ratio. The etching mechanism was interpreted in detail through plasma analysis via optical emission spectroscopy and surface analysis via X-ray photoelectron microscopy. To determine the performance variation according to the alteration in the surface composition of the IGZO thin films, we investigated the changes in the work function, surface energy, and surface roughness through ultraviolet photoelectron spectroscopy, contact angle measurement, and atomic force microscopy, respectively. After the plasma etching process, the change in work function was up to 280 meV, the thin film surface became slightly hydrophilic, and the surface roughness slightly decreased. This work suggests that plasma etching causes various changes in thin-film surfaces, which affects device performance. [ABSTRACT FROM AUTHOR]

Leukocytes must traverse inflamed tissues to effectively control local infection. Although motility in dense tissues appears to be integrin-independent actin-myosin based, during inflammation changes to the extracellular matrix (ECM) may necessitate distinct motility requirements. Indeed, we found that T cell interstitial motility was critically dependent on RGD-binding integrins in the inflamed dermis. Inflammation-induced deposition of fibronectin was functionally linked to increased αv integrin expression on effector CD4+ T cells. Using intravital multi-photon imaging, we found that CD4+ T cell motility was dependent on αv expression. Selective αv blockade or knockdown arrested TH1 motility in the inflamed tissue and attenuated local effector function. These data show a context-dependent specificity of lymphocyte movement in inflamed tissues that is essential for protective immunity.

Output performance of triboelectric devices critically depends on their surface charge density that is greatly influenced by the dielectric constant of material. However, contrary to polymer composites, the dielectric constant cannot be substantially increased in pure polymers. This study shows that interfacial polarization in bilayer polymer films significantly enhances their dielectric constants, increasing the surface charge density and triboelectric performance. This is the first report of the introduction of interfacial polarization of dielectric materials for the enhancement of triboelectric output performance. The elastic bilayer films consisting of polydimethylsiloxane (PDMS) coated with poly (2,2,2-trifluoroethyl methacrylate) (PTF) and poly (L -lysine) (PLL) as negative and positive triboelectric materials, respectively, are utilized in triboelectric devices, which show a dramatic increase in the dielectric constants (24.4 for PTF-PDMS and 15.2 for PLL-PDMS bilayers at 10 kHz) through interfacial polarization, resulting in significant enhancement of triboelectric performance when compared with hard single-layer films. For proofs of concept, we fabricated a temperature-sensitive triboelectric sensor and vibration-based triboelectric nanogenerator. The sensor showed the highest temperature sensitivities among triboelectric sensors whereas the nanogenerator provided vibration-induced sustainable power for LED operation without rectification, which was attributed to the charge accumulation in the bi-layered dielectric films. We demonstrate that the elastic bilayer films in triboelectric devices exhibit a dramatic increase in the dielectric constants through interfacial polarization, resulting in greatly enhanced surface charge density and triboelectric output performances. As proofs of concept, we develop novel triboelectric applications such as a temperature-sensitive triboelectric sensor with an ultrahigh sensitivity and a vibration-based triboelectric nanogenerator with sustainable power even without rectification. [Display omitted] • Elastic bilayer film shows significant enhancement of triboelectric performance through effective interfacial polarization. • Temperature-responsive triboelectric sensor with the best temperature sensitivity is achieved. • Vibration-induced triboelectric nanogenerator with DC behavior is developed. [ABSTRACT FROM AUTHOR]

Background and Objectives: Studies implicate the lung in moderating systemic immune activation via effects on circulating leukocytes. In this study, we investigated whether targeted expression of the antioxidant extracellular superoxide dismutase (SOD3) within the lung would influence post-ischemic peripheral neutrophil activation and CNS reperfusion injury.Methods: Adult, male mice expressing human SOD3 within type II pneumocytes were subjected to 15 min of transient global cerebral ischemia. Three days post-reperfusion, lung and brain tissue was collected and analyzed by immunohistochemistry for inflammation and injury markers. In vitro motility and neurotoxicity assays were conducted to ascertain the direct effects of hSOD3 on PMN activation. Results were compared against C57BL/6 age and sex-matched controls.Results: Relative to wild-type controls, hSOD3 heterozygous mice exhibited a reduction in lung inflammation, blood-brain barrier damage, and post-ischemic neuronal injury within the hippocampus and cortex. PMNs harvested from hSOD3 mice were also resistant to LPS priming, slower-moving, and less toxic to primary neuronal cultures.Conclusions: Constitutive, focal expression of hSOD3 is neuroprotective in a model of global cerebral ischemia-reperfusion injury. The underlying mechanism of SOD3-dependent protection is attributable in part to effects on the activation state and toxic potential of circulating neutrophils. These results implicate lung-brain coupling as a determinant of cerebral ischemia-reperfusion injury and highlight post-stroke lung inflammation as a potential therapeutic target in acute ischemic cerebrovascular injuries. [ABSTRACT FROM AUTHOR]

Iron nanoparticles (NPs) are widely used for the removal of arsenic from water. In this study, we evaluated the interaction between arsenate (AsO 4 3−) and Fe 2 O 3 -NPs on early seedling growth of Vigna radiata. Seedlings were raised in AsO 4 3− and Fe 2 O 3 -NPs, alone and in combination. While Fe 2 O 3 -NPs slightly promoted seedling growth, AsO 4 3− reduced seedling growth drastically. AsO 4 3--induced decline in the seedling growth was recovered by Fe 2 O 3 -NPs. In contrast, equivalent concentrations of FeCl 3 , alone and together with AsO 4 3−, inhibited seed germination completely. Lower arsenic content in seedlings raised in the presence of Fe 2 O 3 -NPs indicated that Fe 2 O 3 -NPs restricted arsenic uptake. Ability of Fe 2 O 3 -NPs to restrict the arsenic uptake of the seedlings was due to adsorption of AsO 4 3−, as revealed by transmission and scanning electron microscopy. Non-toxic levels of iron in seedlings were due to restriction of Fe 2 O 3 -NPs to root-surface. AsO 4 3− enhanced the ferric chelate reductase activity of root which was recovered by Fe 2 O 3 -NPs. The AsO 4 3--induced oxidative stress, evident from high levels of proline, H 2 O 2 and malondialdehyde, and lowered root oxidisability was ameliorated by Fe 2 O 3 -NPs. AsO 4 3-induced enhancement in total antioxidant capacity, superoxide dismutase and catalase activity, and decline in guaiacol peroxidase activity were antagonized by Fe 2 O 3 -NPs. Our findings reveal that Fe 2 O 3 -NPs provide effective resistance/amelioration to arsenic toxicity by reducing arsenic availability to plants. Image 1 • Fe 2 O 3 nanoparticles reduce arsenic uptake in Vigna radiata seedlings. • Fe 2 O 3 nanoparticles reduce arsenic availability to seedlings via sorption. • Fe 2 O 3 nanoparticles restricted to root surface limit transport of toxic iron levels. • Fe 2 O 3 nanoparticles antagonise arsenate induced oxidative stress in seedlings. [ABSTRACT FROM AUTHOR]

• Synthesis of dynamic polyacrylate urethane urea networks containing hindered urea groups. • Control of the material properties of the polymer networks using different HU adducts. • Quantitative evaluation of the scratch-healing performances using a micro-scratch tester. • Excellent mechanical and scratch-resistant properties. • Better scratch-healable performance over commercial clear coats. A series of dynamic polyacrylate urethane urea networks containing hindered urea (HU) groups (C-HU-ethylene glycol, C-HU-EG; C-HU-tetra(ethylene glycol), C-HU-TEG; C-HU-poly(ethylene glycol), C-HU-PEG) were successfully synthesized for use in automotive clearcoats. The material properties of the clearcoats were controlled using different HU adducts and by adjusting their contents in the polymer networks. The indentation hardness (H IT), modulus (E IT), thermal stability (T d), and glass-transition temperature (T g) of the polymer networks were characterized by nano-indentation tests, thermogravimetric analysis, dynamic mechanical analysis, and differential scanning calorimetry, respectively. The scratch-resistance and healing performances of the polymer networks were evaluated quantitatively using a micro-scratch tester in conjunction with optical microscopy. The results reveal that the C-HU-TEG polymer networks not only exhibited physical properties most similar to those of the commercial clearcoat (T30) but also demonstrated the best self-healing performance. The balanced chemical structure of the HU-TEG adduct between the flexible unit (TEG) and the rigid unit (IPDI, urea, and urethane bond) played an important role of increasing scratch-healing performance while maintaining the clearcoat material properties. [ABSTRACT FROM AUTHOR]

[Display omitted] • Reduction of oxygen vacancy concentration in SrTiO3 thin films by O2 plasma treatment. • Defect control through a low-temperature process. • Changes in band gap and work function of SrTiO3 thin films by oxygen plasma treatment. • SrTiO3-based capacitor with an improved dielectric constant in the low-frequency region. Perovskite materials, specifically strontium titanate (SrTiO 3 , STO) thin films, have gained significant attention in materials science and electronics owing to their unique properties. However, low-temperature fabrication via sputtering can introduce oxygen vacancies that compromise film quality. O 2 plasma treatment (OPT) has the potential to improve film properties, such as bond recomposition, electrical conductivity, and optical properties, by reducing the number of oxygen vacancies. In this study, STO films treated by O 2 plasma were characterized using analytical techniques to understand the OPT-induced microstructural, morphological, and optical changes in these films. In addition, the possibility of improving device properties by low-temperature processes was confirmed by exploring the correlation between the number of oxygen vacancies reduced by the OPT process and the enhanced film properties. This result is expected to promote the application of STO thin films in flexible electronic devices and display components and provides insights into the role of oxygen vacancies and the effectiveness of OPT as a low-temperature solution for reducing their number. [ABSTRACT FROM AUTHOR]

With a diffusion-assisted post-crosslinking method, polymer microspheres containing epoxy groups are crosslinked with ethylenediamine (EDA), gradually diffusing and reacting in the particles via amine/epoxy ring-opening reactions as confirmed by FT-IR and DSC results. Using a microcompression test, we find that the mechanical property (deformability under different applied force, breaking points, and recoverability) of the crosslinked microspheres is varied when different amounts of EDA are used in the system, resulting from different crosslinking density of the particles. An additional feature of the EDA treatment is to generate amine groups on the surface of the microspheres, enabling us to produce hybrid microspheres. We exploit them as immobilization sites for gold nanoparticles, forming gold-coated crosslinked microspheres. We also introduce a sequential functionalization method to fabricate crosslinked microspheres with selective functional groups on the surface. This approach can be a facile method to produce functional microspheres with controlled mechanical and surface properties. [ABSTRACT FROM AUTHOR]

Flexible and stretchable electronics have emerged as a groundbreaking technology with wide-ranging applications, including wearable devices, medical implants, and environmental monitoring systems. Among their numerous applications, hydrogen sensing represents a critical area of research, particularly due to hydrogen's role as a clean energy carrier and its explosive nature at high concentrations. This review paper provides a comprehensive overview of the recent advancements in flexible and stretchable electronics tailored for resistive hydrogen sensing applications. It begins by introducing the fundamental principles underlying the operation of flexible and stretchable resistive sensors, highlighting the innovative materials and fabrication techniques that enable their exceptional mechanical resilience and adaptability. Following this, the paper delves into the specific strategies employed in the integration of these resistive sensors into hydrogen detection systems, discussing the merits and limitations of various sensor designs, from nanoscale transducers to fully integrated wearable devices. Special attention is paid to the sensitivity, selectivity, and operational stability of these resistive sensors, as well as their performance under real-world conditions. Furthermore, the review explores the challenges and opportunities in this rapidly evolving field, including the scalability of manufacturing processes, the integration of resistive sensor networks, and the development of standards for safety and performance. Finally, the review concludes with a forward-looking perspective on the potential impacts of flexible and stretchable resistive electronics in hydrogen energy systems and safety applications, underscoring the need for interdisciplinary collaboration to realize the full potential of this innovative technology.

The utilization of triboelectric materials has gained considerable attention in recent years, offering a sustainable approach to energy harvesting and sensing technologies. Biomass-derived materials, owing to their abundance, renewability, and biocompatibility, offer promising avenues for enhancing the performance and versatility of triboelectric devices. This paper explores the synthesis and characterization of biomass-derived materials, their integration into triboelectric nanogenerators (TENGs), and their applications in energy harvesting, self-powered sensors, and environmental monitoring. This review presents an overview of the emerging field of advanced triboelectric applications that utilize the unique properties of biomass-derived materials. Additionally, it addresses the challenges and opportunities in employing biomass-derived materials for triboelectric applications, emphasizing the potential for sustainable and eco-friendly energy solutions.

The depletion of reliable energy sources and the environmental and climatic repercussions of polluting energy sources have become global challenges. Hence, many countries have adopted various renewable energy sources including hydrogen. Hydrogen is a future energy carrier in the global energy system and has the potential to produce zero carbon emissions. For the non-fossil energy sources, hydrogen and electricity are considered the dominant energy carriers for providing end-user services, because they can satisfy most of the consumer requirements. Hence, the development of both hydrogen production and storage is necessary to meet the standards of a "hydrogen economy". The physical and chemical absorption of hydrogen in solid storage materials is a promising hydrogen storage method because of the high storage and transportation performance. In this paper, physical hydrogen storage materials such as hollow spheres, carbon-based materials, zeolites, and metal-organic frameworks are reviewed. We summarize and discuss the properties, hydrogen storage densities at different temperatures and pressures, and the fabrication and modification methods of these materials. The challenges associated with these physical hydrogen storage materials are also discussed.

Multifunctional wearable devices detect electric signals responsive to various biological stimuli and monitor present body motions or conditions, necessitating flexible materials with high sensitivity and sustainable operation. Although various dielectric polymers have been utilized in self-powered wearable applications in response to multiple external stimuli, their intrinsic limitations hinder further device performance enhancement. Because triboelectric devices comprising dielectric polymers are based on triboelectrification and electrostatic induction, multilayer-stacking structures of dielectric polymers enable significant improvements in device performance owing to enhanced interfacial polarization through dissimilar permittivity and conductivity between each layer, resulting in self-powered high-performance wearable devices. Moreover, novel triboelectric polymers with unique chemical structures or nano-additives can control interfacial polarization, allowing wearable devices to respond to multiple external stimuli. This review summarizes the recent insights into multilayered functional triboelectric polymers, including their fundamental dielectric principles and diverse applications.

Mechanochromic smart membranes capable of optical modulation have great potential in smart windows, artificial skins, and camouflage. However, the realization of high-contrast optical modulation based on light scattering activated at a low strain remains challenging. Here, we present a strategy for designing mechanochromic scattering membranes by introducing a Young's modulus mismatch between the two interdigitated polydimethylsiloxane phases with weak interfaces in a periodic three-dimensional (3D) structure. The refractive index-matched interfaces of the nanocomposite provide a high optical transparency of 93%. Experimental and computational studies reveal that the 3D heterogeneity facilitates the generation of numerous nanoscale debonds or "nanogaps" at the modulus-mismatching interfaces, enabling incident light scattering under tension. The heterogeneous scatterer delivers both a high transmittance contrast of >50% achieved at 15% strain and a maximum contrast of 82%. When used as a smart window, the membrane demonstrates effective diffusion of transmitting sunlight, leading to moderate indoor illumination by eliminating extremely bright or dark spots. At the other extreme, such a 3D heterogeneous design with strongly bonded interfaces can enhance the coloration sensitivity of mechanophore-dyed nanocomposites. This work presents insights into the design principles of advanced mechanochromic smart membranes.

Energy harvesting devices based on the triboelectric effect have attracted great attention because of their higher output performance compared to other nanogenerators, which have been utilized in various wearable applications. Based on the working mechanism, the triboelectric performance is mainly proportional to the surface charge density of the triboelectric materials. Various approaches, such as modification of the surface functional group and dielectric composition of the triboelectric materials, have been employed to enhance the surface charge density, leading to improvements in triboelectric performances. Notably, tuning the dielectric properties of triboelectric materials can significantly increase the surface charge density because the surface charge is proportional to the relative permittivity of the triboelectric material. The relative dielectric constant is modified by dielectric polarization, such as electronic, vibrational (or atomic), orientation (or dipolar), ionic, and interfacial polarization. Therefore, such polarization represents a critical factor toward improving the dielectric constant and consequent triboelectric performance. In this review, we summarize the recent insights on the improvement of triboelectric performance via enhanced dielectric polarization.

Hollow SnO2 spheres functionalized by Au catalysts were synthesized via the use of Au-decorated block copolymer (Au-BCP) sphere templates. Uniformly distributed Au nanoparticles on BCP spheres were prepared by the infiltration of Au precursors into polystyrene-b-poly(4-vinylpyridine) (PS-b-P4VP) spheres. A thin SnO2 layer was coated on the Au-BCP spheres using RF sputtering at room temperature without morphological deformation of the spheres. The Au nanoparticles were uniformly transferred from the Au-BCP spheres to the inner shells of the hollow SnO2 spheres followed by decomposition of BCP spheres. The Au-loaded hollow SnO2 spheres exhibited a superior H2S sensitivity (Rair/Rgas = 17.4 at 5 ppm) with remarkably selective characteristics with a minor response (Rair/Rgas < 2.5 at 5 ppm) toward other interfering gases. Our results pave the way for a new catalyst loading method using Au-BCP spheres for the uniformly distributed Au NPs on the SnO2 layers.