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Tellurium exhibits exceptional intrinsic electronic properties. However, investigations into the modulation of tellurium's electronic properties through physical modification are notably scarce. Here, we present a comprehensive study focused on the evolution of the electronic properties of tellurium crystal flakes under plasma irradiation treatment by employing conductive atomic force microscopy and Raman spectroscopy. The plasma-treated tellurium experienced a process of defect generation through lattice breaking. Prior to the degradation of electronic transport performance due to plasma irradiation treatment, we made a remarkable observation: in the low-energy region of hydrogen plasma-treated tellurium, a notable enhancement in conductivity was unexpectedly detected. The mechanism underlying this enhancement in electronic transport performance was thoroughly elucidated by comparing it with the electronic structure induced by argon plasma irradiation. This study not only fundamentally uncovers the effects of plasma irradiation on tellurium crystal flakes but also unearths an unprecedented trend of enhanced electronic transport performance at low irradiation energies when utilizing hydrogen plasma. This abnormal trend bears significant implications for guiding the prospective application of tellurium-based 2D materials in the realm of electronic devices. [ABSTRACT FROM AUTHOR]

Tellurium exhibits exceptional intrinsic electronic properties. However, investigations into the modulation of tellurium’s electronic properties through physical modification are notably scarce. Here, we present a comprehensive study focused on the evolution of the electronic properties of tellurium crystal flakes under plasma irradiation treatment by employing conductive atomic force microscopy and Raman spectroscopy. The plasma-treated tellurium experienced a process of defect generation through lattice breaking. Prior to the degradation of electronic transport performance due to plasma irradiation treatment, we made a remarkable observation: in the low-energy region of hydrogen plasma-treated tellurium, a notable enhancement in conductivity was unexpectedly detected. The mechanism underlying this enhancement in electronic transport performance was thoroughly elucidated by comparing it with the electronic structure induced by argon plasma irradiation. This study not only fundamentally uncovers the effects of plasma irradiation on tellurium crystal flakes but also unearths an unprecedented trend of enhanced electronic transport performance at low irradiation energies when utilizing hydrogen plasma. This abnormal trend bears significant implications for guiding the prospective application of tellurium-based 2D materials in the realm of electronic devices.

Mechanical properties of plasma-irradiated and surface-coated wood plastic composites (WPCs) have been investigated in this paper. WPCs were developed by injection molding technique using wood fiber (WF) as reinforcement and polypropylene (PP) as matrix. The short, discontinuous WF was compounded with thermoplastic PP at varying weight fractions of 0 wt%, 25 wt% (WP25), and 50 wt% (WP50) to yield tensile test specimens in accordance with JIS K7139-A32 standards. Subsequently, plasma treatment was performed on the test-pieces, followed by surface coating by immersion in acrylic resin liquid containing homogeneously dispersed TEMPO-oxidized cellulose nanofibers (CNF). The results indicate an increase in surface roughness after plasma irradiation, but surface coating of the specimens with acrylic paint and CNF decreased their surface roughness by ∼50% in comparison to the untreated specimens. Plasma treatment and surface coating also increased the tensile strength of neat PP, WP25 and WP50 specimens by 5.4–7.1%, 3.5–3.7% and 3.0–3.6%, respectively, whereas their fracture strains tended to decrease. Compared to the untreated specimens, the surface-coated specimens generally displayed higher tensile strength. This finding is a corroboration that the observed increase in strength is highly contingent on the adhesion between the specimen surface and the coating layer than on the improvement in surface roughness. Thus, it is inferable that surface coating could be of great importance in enhancing the mechanical performance of WPCs. [ABSTRACT FROM AUTHOR]

Recently we have shown that thin (33 to 55 nm) oxide films on tungsten (W) prevent deuterium (D) uptake from a low-temperature plasma (5 eV/D; 370 K; 1.4 × 1024 D/m2) into metallic W. Here we continue this investigation with higher D fluence up to 2.3 × 1025 D/m2 and, additionally, with higher D energies up to 38 eV/D or a higher sample temperature of 500 K. We investigate the reduction mechanism of the oxide and determine under which conditions the permeation barrier effect for D breaks down. We show that during prolonged plasma exposure at 5 eV/D and 370 K, the W-enriched zone that forms at the surface of the oxide stops growing and continues to protect the oxide beneath it against further reduction. For a fluence of 1.6 × 1025 D/m2, an originally 55 nm thick oxide film reduces D uptake into the metal by 99 %. D enters the metal solely by small cracks in the oxide that form during reduction by the plasma. For higher temperature or D energies, the reduction becomes stronger and more inhomogeneous. D uptake into the metal increases proportional to the area of oxide/metal interface on which the oxide is reduced. The new experiments confirm our previous assumption that D uptake into W is blocked due to the difference in enthalpy of solution of D in W oxide and metallic W. D can only enter the metal once the oxide at the interface is sufficiently reduced. Based on the obtained oxide reduction rates, we made a first tentative estimate of the relevance of naturally occurring W oxide films for D uptake in the plasma-facing components of a fusion reactor. We found that the natural oxide will have none or only a very minor effect in this case.

Abstract Oxygen vacancies (V o) in electrocatalysts are closely correlated with the hydrogen evolution reaction (HER) activity. The role of vacancy defects and the effect of their concentration, however, yet remains unclear. Herein, Bi2O3, an unfavorable electrocatalyst for the HER due to a less than ideal hydrogen adsorption Gibbs free energy (ΔG H*), is utilized as a perfect model to explore the function of V o on HER performance. Through a facile plasma irradiation strategy, Bi2O3 nanosheets with different V o concentrations are fabricated to evaluate the influence of defects on the HER process. Unexpectedly, while the generated oxygen vacancies contribute to the enhanced HER performance, higher V o concentrations beyond a saturation value result in a significant drop in HER activity. By tunning the V o concentration in the Bi2O3 nanosheets via adjusting the treatment time, the Bi2O3 catalyst with an optimized oxygen vacancy concentration and detectable charge carrier concentration of 1.52 × 1024 cm−3 demonstrates enhanced HER performance with an overpotential of 174.2 mV to reach 10 mA cm−2, a Tafel slope of 80 mV dec−1, and an exchange current density of 316 mA cm−2 in an alkaline solution, which approaches the top-tier activity among Bi-based HER electrocatalysts. Density-functional theory calculations confirm the preferred adsorption of H* onto Bi2O3 as a function of oxygen chemical potential (∆μ O) and oxygen partial potential (P O2) and reveal that high V o concentrations result in excessive stability of adsorbed hydrogen and hence the inferior HER activity. This study reveals the oxygen vacancy concentration-HER catalytic activity relationship and provides insights into activating catalytically inert materials into highly efficient electrocatalysts.

Half-doped manganites has proven itself to be candid material for different magnetic-based devises. Various physical properties of pellet size half-doped La0.5Sr0.5MnO3 manganite treated with oxygen plasma and its comparison with the pristine samples is reported in this article. The impact of plasma irradiation on different properties such as structure, thermoelectric power and electrical resistivity were studied and compared before exposure. The crystal structure or symmetry remains unaffected due to plasma exposure. The Mn4+/Mn3+ ratio decreases after exposing to plasma compared to the pristine samples. It is observed that La0.5Sr0.5MnO3 samples exhibit insulating behaviour before and after plasma exposure. The resistivity increases appreciably after plasma treatment which may be credited to the reduction in the bond angle of Mn–O–Mn as well as the creation of oxygen vacancies. The negativity of the thermopower is seen at all temperatures attributing it to the electrons behaving as the dominant charge carriers and also shows that the magnitude is temperature dependent. [ABSTRACT FROM AUTHOR]

Tungsten (W) plays a crucial role in the lifetime of the plasma-facing components of DEMO. In order to avoid oxidation, W-based alloys have been studied as alternatives to W. In this work, the Monte Carlo SRIM-2013 simulation program was used to calculate the nuclear stopping power, electronic stopping power, amount of target vacancies, displacements, replacement collisions, and total target damage of W, W-Cr-Si, W-Cr-Ti, and W-Cr-Y by hydrogen and helium ion bombardment. It is found that W is resistant to vacancies, atomic displacement, and total damage compared to W-based alloys. [ABSTRACT FROM AUTHOR]

Half-doped manganites has proven itself to be candid material for different magnetic-based devises. Various physical properties of pellet size half-doped La0.5Sr0.5MnO3 manganite treated with oxygen plasma and its comparison with the pristine samples is reported in this article. The impact of plasma irradiation on different properties such as structure, thermoelectric power and electrical resistivity were studied and compared before exposure. The crystal structure or symmetry remains unaffected due to plasma exposure. The Mn4+/Mn3+ ratio decreases after exposing to plasma compared to the pristine samples. It is observed that La0.5Sr0.5MnO3 samples exhibit insulating behaviour before and after plasma exposure. The resistivity increases appreciably after plasma treatment which may be credited to the reduction in the bond angle of Mn–O–Mn as well as the creation of oxygen vacancies. The negativity of the thermopower is seen at all temperatures attributing it to the electrons behaving as the dominant charge carriers and also shows that the magnitude is temperature dependent. [ABSTRACT FROM AUTHOR]

Mechanical properties of plasma-irradiated and surface-coated wood plastic composites (WPCs) have been investigated in this paper. WPCs were developed by injection molding technique using wood fiber (WF) as reinforcement and polypropylene (PP) as matrix. The short, discontinuous WF was compounded with thermoplastic PP at varying weight fractions of 0 wt%, 25 wt% (WP25), and 50 wt% (WP50) to yield tensile test specimens in accordance with JIS K7139-A32 standards. Subsequently, plasma treatment was performed on the test-pieces, followed by surface coating by immersion in acrylic resin liquid containing homogeneously dispersed TEMPO-oxidized cellulose nanofibers (CNF). The results indicate an increase in surface roughness after plasma irradiation, but surface coating of the specimens with acrylic paint and CNF decreased their surface roughness by ∼50% in comparison to the untreated specimens. Plasma treatment and surface coating also increased the tensile strength of neat PP, WP25 and WP50 specimens by 5.4–7.1%, 3.5–3.7% and 3.0–3.6%, respectively, whereas their fracture strains tended to decrease. Compared to the untreated specimens, the surface-coated specimens generally displayed higher tensile strength. This finding is a corroboration that the observed increase in strength is highly contingent on the adhesion between the specimen surface and the coating layer than on the improvement in surface roughness. Thus, it is inferable that surface coating could be of great importance in enhancing the mechanical performance of WPCs.

Poly(vinyl alcohol) (PVA)/polyethersulfone (PES) composite membranes were fabricated using two PVA polymers with molecular weights of 50,000 and 15,000 and different crosslinker agents. The membrane with the top layer consisting PVA 50,000 and formaldehyde as the crosslinker were found to have a better separation factor than the others for pervaporative dehydration of isopropanol. While adding 1.0 wt% graphene oxide could represent a better pervaporation separation factor, 248.7% higher than that of the unfilled membrane, treating the graphene oxide nanosheets using cold plasma irradiation under oxygen atmosphere could yield 47.5% higher separation factor compared to the membrane containing untreated nanosheets owing to higher functional groups on the treated nanosheets that enhance the crosslinking density of the membrane. The best plasma treatment conditions in the selected range were found as 60 s irradiation under 0.3 mbar pressure and device power of 25 watts. The superior performance of the optimal membrane fabricated in the present study was confirmed by comparing the values of normalized pervaporation water index with those in previous studies. [Display omitted] • Incorporating GO improve separation factor of PVA/PES membranes for IPA dehydration. • Plasma treatment of GOs increased their sites yielded 47.5% higher separation factor. • Improvement was related to higher groups on treated GOs and crosslinking density. • Superior normalized pervaporation water index of treated GO membrane was confirmed. [ABSTRACT FROM AUTHOR]

Abstract The lithium polysulfides (LiPS) dissolution into electrolyte as well as consequent shuttle behavior seriously exacerbate the electrochemical performance of lithium–sulfur batteries. Herein, the intrinsic defect of graphene has been tailored by using plasma irradiation. The topological defective carbon structure is demystified into monovacancy and divacancy which effectively promote Li–S redox kinetics by selectively decelerating the generation of soluble high‐order LiPSs and passingly promoting the conversion to final solid products. Theoretical prediction uncovers the selective manipulation of Li–S redox kinetics by defective graphene, facilitating the reduced overpotential effect and uniform deposition of Li2S. Moreover, the divacancy presents a higher activity for Li–S chemistry in contrast with monovacancy. Therefore, the battery achieves superior cyclability with a capacity retention of 88.6% at 1.0 C over 300 cycles. Furthermore, it yields an areal capacity up to 8.5 mAh cm−2 with a sulfur loading of 13.3 mg cm−2.

A single-phase Si-modified β-NiAl coating was formed by direct irradiation of Al-Si plasma in vacuum, which is distinctively different from that of the conventional AlSi slurry-diffusion process that normally generates silicides precipitation. A large amount of nanocavities was observed in the plasma-irradiated coating, which might relate to the formation of the single phase. Oxidation of the two coatings at 1000 ℃ shows that the single-phase coating formed an intact and uniform alumina scale whereas the conventional one formed a void-containing and rumpling scale, indicating the uniquely beneficial effects by forming the single-phase Si-modified β-NiAl coating. • Single-phase Si-modified β-NiAl coating was formed by irradiation of Al-Si plasma. • Nanocavities were observed in the single-phase coating. • Plasma irradiation greatly improved the oxidation resistance of Si-modified β-NiAl. [ABSTRACT FROM AUTHOR]

Highlights: Catalytically inert 2D Bi2O3 is activated for boosting electrochemical hydrogen evolution reaction (HER) via oxygen vacancy concentration modulation. The relationship between the varied oxygen vacancy concentrations and the corresponding HER activity is revealed by both experimental Vo verification and theoretical density-functional theory calculations. This work provides insights into activating catalytically inert materials into high-performance catalysts. Oxygen vacancies (Vo) in electrocatalysts are closely correlated with the hydrogen evolution reaction (HER) activity. The role of vacancy defects and the effect of their concentration, however, yet remains unclear. Herein, Bi2O3, an unfavorable electrocatalyst for the HER due to a less than ideal hydrogen adsorption Gibbs free energy (ΔGH*), is utilized as a perfect model to explore the function of Vo on HER performance. Through a facile plasma irradiation strategy, Bi2O3 nanosheets with different Vo concentrations are fabricated to evaluate the influence of defects on the HER process. Unexpectedly, while the generated oxygen vacancies contribute to the enhanced HER performance, higher Vo concentrations beyond a saturation value result in a significant drop in HER activity. By tunning the Vo concentration in the Bi2O3 nanosheets via adjusting the treatment time, the Bi2O3 catalyst with an optimized oxygen vacancy concentration and detectable charge carrier concentration of 1.52 × 1024 cm−3 demonstrates enhanced HER performance with an overpotential of 174.2 mV to reach 10 mA cm−2, a Tafel slope of 80 mV dec−1, and an exchange current density of 316 mA cm−2 in an alkaline solution, which approaches the top-tier activity among Bi-based HER electrocatalysts. Density-functional theory calculations confirm the preferred adsorption of H* onto Bi2O3 as a function of oxygen chemical potential (∆μO) and oxygen partial potential (PO2) and reveal that high Vo concentrations result in excessive stability of adsorbed hydrogen and hence the inferior HER activity. This study reveals the oxygen vacancy concentration-HER catalytic activity relationship and provides insights into activating catalytically inert materials into highly efficient electrocatalysts. [ABSTRACT FROM AUTHOR]

The structural and electrical properties of Gd1−x Sr x MnO3 manganites pellets with different doping concentrations x (= 0.2,0.3,0.4,0.5) are modified using an easy low-pressure plasma irradiation method. Powder x-ray diffraction studies of the samples revealed that lattice parameters a and c increase with doping as well as plasma exposure except for x = 0.5 for which a decreases. On the contrary, lattice parameter b decreases with doping as well as plasma exposure and is more pronounced. The crystallite size increases with increasing doping concentration both with or without plasma exposure. Plasma exposure tends to decrease the Mn–O–Mn bond angle as well as the Mn–O bond length. The temperature-dependent electrical resistivity of samples reveals that the pristine Gd1−x Sr x MnO3 exhibits insulating behavior for all the doping concentrations. However, the resistivity is enhanced at low temperature for all samples after plasma exposure. The variation of electrical resistivity after plasma exposure may be attributed to the disorder near the grain boundaries and cell volume. The resistivity behavior is unaffected by plasma exposure for all samples. The small polaron hoping model explains the conduction mechanism at high temperature while the conduction at low temperature is attributed to variable range polarons. [ABSTRACT FROM AUTHOR]

According to the studies, damages to the peripheral nerve as a result of a trauma or acute compression, stretching, or burns accounts for a vast range of discomforts which strongly impressed the patient's life quality. Applying highly potent biomolecules and growth factors in the damaged nerve site would promote the probability of nerve regeneration and functional recovery. Tissue plasminogen activator (tPA) is one of the components that can contribute importantly to degenerating and regenerating the peripheral nerves following the injuries occurred and the absence of this biomolecule hinders the recoveries of the nerves. This technique would guarantee the direct accessibility of tPA for the regenerating axons. Structural, physical, and in vitro cytotoxicity evaluations were done before in vivo experiments. In this study, twenty-four mature male rats have been exploited. The rats have been classified into four groups: controls, axotomy, axotomy + scaffold, and axotomy + tPA-loaded scaffold. Four, 8, and 12 weeks post-surgical, the sciatic functional index (SFI) has been measured. After 12 weeks, the spinal cord, sciatic nerve, and dorsal root ganglion specimens have been removed and stereological procedures, immunohistochemistry, and gene expression have been used to analyze them. Stereological parameters, immunohistochemistry of GFAP, and gene expression of S100, NGF, and BDNF were significantly enhanced in tPA-loaded scaffold group compared with axotomy group. The most similarity was observed between the results of control group and tPA-loaded scaffold group. According to the results, a good regeneration of the functional nerve tissues in a short time was observed as a result of introducing tPA. [ABSTRACT FROM AUTHOR]

In this study, Dielectric Barrier Discharge plasma irradiation (DBD) is applied to treatment and improve the properties of the ZnO thin film deposited on the glass substrate as a sensor for glucose detection. The ZnO is prepared via a sol-gel method in this work. ZnO is irradiated by the DBD high voltage plasma to improve of its sensitivity. The optical properties, roughness and surface morphology of the waveguide coated ZnO thin films before and after DBD plasma irradiation are studied in this work. The results showed a significant improvement in the performance of the sensor in the detection of concentrations of glucose solution after plasma irradiation. Where the largest value in sensitivity was equal to 62.7 when the distance between electrodes was 5 cm compared to the sensitivity before irradiation, which was equal to 92. The high response showed in results demonstrating that the fabricated waveguide coated ZnO after plasma irradiation has the excellent potential application as a sensor to detect small concentration of glucose solution. [ABSTRACT FROM AUTHOR]

Stabilization is the most complicated and time-consuming step in the manufacture of carbon fibers (CFs), which is important to prepare CFs with high performance. Accelerated stabilization was successfully demonstrated under effective plasma irradiation-assisted modification (PIM) of mesophase pitch fibers (PFs). The results showed that the PIM treatment could obviously introduce more oxygen-containing groups into PFs, which was remarkably efficient in shortening the stabilization time of PFs with a faster stabilization heating rate, as well as in preparing the corresponding CFs with higher performance. The obtained graphitized fiber (GF-5) from the PF-5 under PIM treatment of 5 min presented a higher tensile strength of 2.21 GPa, a higher tensile modulus of 502 GPa, and a higher thermal conductivity of 920 W/m·K compared to other GFs. Therefore, the accelerated stabilization of PFs by PIM treatment is an efficient strategy for developing low-cost pitch-based CFs with high performance.

In this work we have studied the influence of argon working pressure, substrate temperature, low power plasma irradiation and partial pressure of hydrogen in the RF-magnetron sputtering of indium tin oxide (ITO) thin films on glass substrates. This work aims at identifying the best conditions to achieve good quality ITO films at low temperature for deposition on heat-sensitive substrates. Four sets of samples were prepared which were characterized by X-ray diffraction (XRD), Van der Pauw and transmittance measurements. It was found that structural, electrical and optical properties of the films depend strongly on the deposition parameters. ITO films with a thickness of ~300 nm, displaying a sheet resistance of 68 Ω/sq and average transmittance, in the visible range, of about 90% were produced performing the deposition at low pressure and at room temperature. However, further improvements in the sheet resistance up to a factor of 3 were obtained by decreasing a little more the argon working pressure or applying a low power plasma irradiation or adding a partial pressure of hydrogen to the working gas. Films produced at low working pressures are crystalline and have [222] preferential orientation. The conductivity and transmittance of these films are higher than those of films deposited at high pressures. The electrical resistivity of the ITO thin films decreased sharply either with low power plasma irradiation or the addition of a partial pressure of H 2 to the working gas. All the films showed an average transmittance of over 80% in the visible range. Therefore, as a result of this work we established that the addition of a small partial pressure of H 2 to the working gas during growth allowed us to achieve the main aim of depositing low resistivity ITO films at low substrate temperature suitable for the envisaged applications. At the same time, we concluded that this approach leads to a drastic reduction in the amount of target surface conditioning required every time a new target was installed because it turns the properties of the ITO films more independent of the target surface properties. Unlabelled Image • Optimization of low temperature RF-magnetron sputtering of Indium Tin Oxide Films • We studied the effect of working pressure, temperature, plasma irradiation and H 2. • The favorable route was found to be the addition of a partial pressure of H 2. • ITO film with 248 nm, 23 Ω and a transmittance of 90%, in visible range was produced. [ABSTRACT FROM AUTHOR]

In the article, a hydrogen exchange between the Zr–1%Nb alloy (E110) and the gas ambient was experimentally studied when the samples were irradiated with deuterium and argon plasma ions. It has been established that, upon irradiation with deuterium plasma ions with an energy of E = 650 eV/at, the enhanced absorption of deuterium exceeds the release of hydrogen initially contained in the samples, which leads to their loading with hydrogen isotopes. Adding 30 at.% oxygen to the plasma-forming gas or raising the sample temperature from T = 450 K to T = 600 K, significantly reduces the content of hydrogen isotopes in the sample. Based on the aggregate data obtained by atomic and ion irradiation, a mechanism of hydrogen exchange between zirconium alloy and gas ambient is proposed. The process includes three stages: reactions on the oxidized surface of the zirconium alloy (surface hydroxylation and formation of water molecules); reactions at the metal-oxide interface; transfer of hydrogen isotopes through the surface oxide layer in both directions due to hopping between neighboring oxygen ions. Surface reactions caused by irradiation of atoms and ions trigger the hydrogen exchange. The proposed model agrees with the experimental data on the irradiation of the E110 alloy with atoms and ions of hydrogen isotopes. • Plasma ion irradiation causes hydrogen exchange between zirconium alloy and a gaseous ambient. • Irradiation conditions are found to rise or reduce the hydrogen content in zirconium. • A mechanism of the hydrogen exchange under atomic or ion irradiation is formulated. • Surface reactions caused by irradiating species play a key role in the process. [ABSTRACT FROM AUTHOR]

Helium-plasma irradiation induces nanostructure formation on metal surfaces. This study investigated the photocatalytic performance of tungsten (W) oxide nanostructures formed on a thin film and the loading effects of noble metals. Methylene blue (MB) degradation was performed, and the performance of different nanostructured samples formed on thin-film and sheet W with changing the oxidization temperatures was compared; the differences were discussed in terms of the oxidation degree and vacancies. Moreover, noble metals (Pt, Ag, Au) were loaded onto the nanostructured sample oxide by magnetron sputtering as cocatalysts. The MB degradation ability was significantly enhanced by Pt loading. The results showed that nanostructuring and Pt support by using dry processes are novel routes for fabricating highly active photocatalysts.

Growth of helium bubbles near the surface of metals leads to various morphology changes when sufficient helium ions are continuously implanted on the surface. In this study, low energy (< 100 eV) helium plasma irradiations to various noble metals were conducted, and consequent surface morphology changes were analyzed. It was found that fiberform nanostructures were formed by the helium plasma irradiation on rhodium and ruthenium thin films, which were deposited by magnetron sputtering, and on platinum and iridium wires. Growth of fiberform structures were not identified on gold, silver, and palladium samples exposed to helium plasmas even though the irradiations were conducted at various surface temperatures, though pinholes were observed on palladium surface. We discussed the relation between the morphology changes and material properties. [ABSTRACT FROM AUTHOR]

Ar/O plasma irradiation is proposed for post-treatment of vanadium dioxide (VO2) films. Oxidation and surface migration were observed in the VO2 films following irradiation. This combined effect leads to an effective stoichiometry refinement and microstructure reconstruction in the interfacial area. A notable improvement in luminous transmittance and an enhancement in phase transition performance of the treated VO2 films were achieved. Compared with that of as-deposited VO2 films, the electrical phase transition amplitude of treated films increased more than two-fold. The relative improvement in luminous transmittance (380–780 nm) is 47.4% (from 25.1% to 37%) and the increase in solar transmittance is 66.9% (from 29.9% to 49.9%), which is comparable to or better than the previous work using anti-reflection (AR) coatings or doping methods. The interfacial boundary state proved to be crucial and Ar/O plasma irradiation offers an effective approach for further refinement of thermochromic VO2 films.

The chemical oxidation method can be used to mass-produce graphene oxides (GOs) from highly oriented pyrolytic graphite. However, numerous oxygen-containing functional groups (hydroxyl, epoxy, carbonyl, etc.) exist in typical GO surfaces, resulting in serious electrical losses. Hence, GO must be processed into reduced graphene oxide (rGO) by the removal of most of the oxygen-containing functional groups. This research concentrates on the reduction efficiency of GO films that are manufactured using atmospheric-pressure and continuous plasma irradiation. Before and after sessions of plasma irradiation with various irradiation times, shelters, and working distances, the surface, physical, and electrical characteristics of homemade GO and rGO films are measured and analyzed. Experimental results showed that the sheet resistance values of rGO films with silicon or quartz shelters were markedly lower than those of GO films because the rGO films were mostly deprived of oxygen-containing functional groups. The lowest sheet resistance value and the largest carbon-to-oxygen ratio of typical rGO films were approximately 90 Ω/sq and 1.522, respectively. The intensity of the C–O bond peak in typical rGO films was significantly lower than that in GO films. Moreover, the intensity of the C–C bond peak in typical rGO films was considerably higher than that in GO films.

High-density polyethylene (PE) foils were modified by an Ar+ plasma discharge and subsequent grafting with biomolecules, namely glycine (Gly), polyethylene glycol (PEG), bovine serum albumin (BSA), colloidal carbon particles (C) or BSA and C (BSA + C). As revealed by atomic force microscopy (AFM), goniometry and Rutherford Backscattering Spectroscopy (RBS), the surface chemical structure and surface morphology of PE changed dramatically after plasma treatment. The contact angle decreased for the samples treated by plasma, mainly in relation to the formation of oxygen structures during plasma irradiation. A further decrease in the contact angle was obvious after glycine and PEG grafting. The increase in oxygen concentration after glycine and PEG grafting proved that the two molecules were chemically linked to the plasma-activated surface. Plasma treatment led to ablation of the PE surface layer, thus the surface morphology was changed and the surface roughness was increased. The materials were then seeded with vascular smooth muscle cells (VSMC) derived from rat aorta and incubated in a DMEM medium with fetal bovine serum. Generally, the cells adhered and grew better on modified rather than on unmodified PE samples. Immunofluorescence showed that focal adhesion plaques containing talin, vinculin and paxillin were most apparent in cells on PE grafted with PEG or BSA + C, and the fibres containing α-actin, β-actin or SM1 and SM2 myosins were thicker, more numerous and more brightly stained in the cells on all modified PE samples than on pristine PE. An enzyme-linked immunosorbent assay (ELISA) revealed increased concentrations of focal adhesion proteins talin and vinculin and also a cytoskeletal protein β-actin in cells on PE modified with BSA + C. A contractile protein α-actin was increased in cells on PE grafted with PEG or Gly. These results showed that PE activated with plasma and subsequently grafted with bioactive molecules and colloidal C particles, especially with PEG and BSA + C, promotes the adhesion, proliferation and phenotypic maturation of VSMC.

Surface charge density greatly influences triboelectric properties and tribological behavior. Given the limitations of current techniques for regulating surface charge, a novel plasma-irradiation-based surface treatment was used to enhance the triboelectric properties and optimize the tribological behavior of polyimide (PI) films. An in-situ two-step Ar+O 2 reactive ion etching (RIE) plasma treatment was used to etch the surface of the PI films to enhance the triboelectric performance of PI-PA11-based triboelectric nanogenerators (TENGs). The generation of granular nanostructures on the PI film surface enhanced the effective contact area between triboelectric layers. The C-O and C O content was also greatly increased, improving the electron affinity of the PI films. At the same time, to obtain a fully antistatic PI surface in a PI-PVDF-based TENG, the optimal irradiation time was calculated. In addition, to control the tribological behavior, the surface charge of PI film was successfully eliminated by a one-step Ar plasma irradiation, and the regulation of the coefficient of friction was realized, which significantly improved the friction stability and wear resistance of the material. This new approach can find wide applications in energy harvesting, industrial production, electronic circuit, and other applications. [Display omitted] • The effective regulation of surface morphology and surface chemical structure has been realized. • Triboelectric properties can be controlled by two-step Ar+O 2 plasma irradiation and realize energy harvesting or antistatic. • Tribological behaviors can be controlled by one-step Ar plasma irradiation, which can regulate coefficient of friction. • The regulation mechanism on triboelectric properties and tribological behaviors of PI films has been investigated. [ABSTRACT FROM AUTHOR]

Background & objectives: Various conventional methods such as gaseous, vapour and misting systems, fogging, manual spray and wipe techniques employing a number of chemical agents are used for decontamination of enclosed spaces. Among all these methods, use of aerosolized formaldehyde is the most preferred method due to cost-effectiveness and practical aspects. However, being extremely corrosive in nature generating very irritating fumes and difficulty in maintaining a high level of gas concentration, many laboratories prefer the vaporization of hydrogen peroxide (H2O2) as an alternative. We present here the results of using H2O2 vapour in combination with plasma irradiation for quick decontamination of closed chambers. Methods: The present study describes a decontamination method, using plasma irradiation in combination with H2O2 (5%). Effect of plasma irradiation and H2O2 on the viability of bacterial spores (Bacillus subtilis), Chikungunya and Kyasanur Forest Disease viruses was assessed. Results: Data suggest that with the combination of H2O2 vapour and plasma irradiation, within short time (three minutes), decontamination of surfaces and space volume could be achieved. Although it showed damage of spores present on the strips, it did not show any penetration power. Interpretation & conclusions: The results were encouraging, and this method was found to be efficient for achieving surface sterilization in a short time. This application may be useful in laboratories and industries particularly, those working on clean facility concept following good laboratory and manufacturing practices. [ABSTRACT FROM AUTHOR]

[Display omitted] • The luminous position of BNNSs in the PL emission spectrum can be regulated by controlling hydrogen plasma irradiation. • The hydrogen plasma treatment on BNNSs can form B-O bonds while O substitutes N. • The population of oxygen related defects play important role in remediation of nonradiative recombination pathways. Atomic defects capable of hosting optically active centers in hexagonal boron nitride (h -BN) demonstrate a rich spin and optoelectronic physics that can be exploited for next-generation nanoelectronics and photonics. The precise controlling of these active defects is thus of particular importance. Here, we demonstrate the modulation of optoelectronic properties of atomically thin h -BN nanosheets (BNNSs) based on defect engineering via hydrogen plasma irradiation. Detailed studies resolve the generation of point defects and oxygen related defects uniformly in h -BN lattice after treated by hydrogen plasma. These tailored defects can lead to stable room-temperature luminescent emissions varying from 440 nm (ca. 2.8 eV) to 580 nm (ca. 2.1 eV) in BNNSs and multiple recombination channels. In addition, we show significant variations in both lattice structure and energy bandgap in BNNSs that can be tuned by the hydrogen plasma treatment. Density functional theory calculations verify the nature of the defect-induced optoelectronic behavior. These results are highly valuable for the fabrication of future two-dimensional semiconducting electronics, optoelectronics, and spintronics. [ABSTRACT FROM AUTHOR]