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• High-temperature in-situ XAFS and SAXS measurements of nio-doped sodium borosilicate glass and melt were successfully carried out under controlled thermal history. • The Ni2+ ions in borosilicate glass were 6-coordinated (O h) and showed green appearance. The coordination number decreased rapidly when heated above 1000 °C under in-situ measurement. The coordination number seemed to be turned smaller than 5, as the glass quenched from 1000 °C was brown-colored. • High-temperature in-situ time-resolved SAXS measurements show a rapid decrease in scattering intensity during heating from 800 °C up to 1000 °C as the fractionated glass is heated. This is in good agreement with the rapid change in the coordination number of Ni2+, suggesting that the compositional heterogeneity caused by the phase separation affected the ligand field of Ni2+. High-temperature in-situ Ni-K edge XAFS and SAXS measurements were conducted on borosilicate glasses with low alkali content with/without phase separation tendency, which have been investigated to understand immiscibility into silica-rich phase and borate-rich one on the samples heat-treated at certain temperature followed by fast quenching. In this work, using in-situ analyzing techniques, in-situ time-domain evolution of phases along temperature and time was obtained to understand high-temperature behavior. Ni2+ ion probes phase separation behavior using its high selectivity favoring borate-rich phase and sensitivity to electron donating ability of surrounding oxygens. Taking advantage of these characters, local compositional change was tracked during phase separation under heat treatment. Time-resolved SAXS profiles revealed the speed of phase transformation in addition to changes of morphology at respective temperature. The phase-separation transformation mechanism via different phase separation scheme (homogeneous → spinodal → binodal →homogeneous) was clearly described, revealing effect of NiO clustering at higher temperature. [ABSTRACT FROM AUTHOR]

Freestanding ultrathin glass film (UGF) of 45S5 bioglass was successfully bonded on a Ti substrate by the room‐temperature bonding method. 45S5 UGFs with a thickness of 1~4 μm were fabricated by the glass‐blowing technique, and the UGF was attached on the Ti plate at room temperature with a water layer between them. The bonding strength was about 370 mJ/m2 just after bonding, and it increased during storing in the ambient atmosphere at room temperature and reached about 900 mJ/m2 after 9 hours storage. The interfaces of the UGF and Ti substrate during the bonding process were analyzed by an X‐ray photoelectron spectroscopy. The as‐prepared UGF was found to have surface layers with a high content of Na2O and low content of SiO2, and the dissolution of Na2O‐rich component into water layer induced depolymerization and polymerization of SiO2 network to form Si‐O‐Si bonds between the UGF and Ti plate and then to increase the bonding strength during storage. This work presents the simple technique to laminate the bioactive glass layer on the surface of the metal without post heat treatment. [ABSTRACT FROM AUTHOR]

Combining femtosecond laser exposure with chemical etching enables the fabrication of arbitrary 3D shapes in fused silica with micron precision. Here, we investigate the use of this process combined with additional tuning of the material properties for controlling the vibrational behavior of silica microcantilevers through an acoustic black hole (ABH) effect. This effect, caused by a tapered profile at the cantilever's end, enables the trapping of propagating acoustic waves. Such cantilevers with ABH design show a remarkable amplitude decrease in the resonance peak without adding any damping material as demonstrated experimentally. Finally, using Fourier‐transform infrared spectroscopy (FTIR), we observe residual effects of the laser exposure at the surface of the specimen that have noticeable influence on the dynamic behavior of the device. [ABSTRACT FROM AUTHOR]

Tellurite glass thin film was successfully bonded on a silicate glass substrate by the direct‐bonding (DB) method. Glass film (thickness 1‐3 μm) was fabricated by the glassblowing technique and the DB process was performed at room temperature at relative humidity (RH) of 62% or 15%. The surface adhesive strengths of the glass films bonded at 15% and 62% RH were measured as 250 and 96 mJ/m2, respectively, by the Obreimoff‐Metsik method. The hydroxyl (–OH) functional groups on the interface between the film and silicate glass were analyzed by Fourier‐transform infrared spectroscopy. The major bonding forces between the tellurite thin film and silicate glass were hydrogen bonds at 62% RH and bonds between Te on the tellurite glass and O on the silicate glass were concerned at 15% RH. These forces, contributed by Si–OH, were important for bond formation at 62%. The large amounts of water and OH groups on the silicate glass, determined by thermogravimetric analysis, indicated a weaker bonding process at 62% RH. This work will contribute toward reliable, high‐integrity components for integrated optical circuits, which are increasingly needed for high‐throughput data transfer. [ABSTRACT FROM AUTHOR]

Abstract A modified liquid phase deposition process named "gas-assisted liquid phase deposition (G-LPD)" was developed to fabricate oxide films at a synthesis temperature below 100 °C and atmospheric pressure using readily available metal salts such as nitrates and chlorides. One of the major points of this process was that a moderately low initial pH of the aqueous metal salt solution was required. In addition, a slight increase of the hydroxide ion concentration was required to facilitate oxide deposition through an equilibrium reaction between metal ions and oxides. Gaseous ammonia generated from aqueous hexamethylenetetramine solution slightly increased the hydroxide ion concentration of the metal salt solution. This process required only one sealed vessel and two beakers, one of which contained an aqueous solution of metal salts and the other hexamethylenetetramine solution. The slow rate of the equilibrium reaction induced heterogeneous nucleation at solid–liquid interfaces, resulting in film formation. Crystalline ceria films were fabricated at 60 °C by keeping the pH almost constant in the range from 4.6 to 5.2. The thickness of ceria films fabricated on polyether sulfone substrates from aqueous 0.05 M cerium nitrate solutions after 3, 7, and 14 days were about 120, 210, and 380 nm, respectively. Graphical abstract Unlabelled Image Highlights • CeO 2 films were fabricated at 60 °C without seed layers by gas-assisted LPD. • Preferable pH was between equilibrium pH values for Ce3+–CeO 2 and Ce3+–Ce(OH) 4. • Gradual increase in [OH−] induced nucleation at solid-liquid interface. • Fabricated films had good adhesion and were not exfoliated by ultrasonic washing. [ABSTRACT FROM AUTHOR]

• Na 2 O-B 2 O 3 -SiO 2 glass plate phase separated in spinodal was partially remelted and homogenized by laser heating, using embedded NiO as CW-laser (λ=1064 nm) absorber and heat center. • The laser irradiated area of glass turned brown with high chemical durability, indicating the local environment change of Ni2+ ion along with miscibility change. • Similar color change was observed when the glass is water-quenched from 1000°C melt, which has homogeneous structure frozen at room temperature. • The color of Ni2+ ion reflects miscible-immiscible behavior of sodium borosilicate glass. Na 2 O-B 2 O 3 -SiO 2 glass plate phase separated in spinodal was partially remelted and homogenized by laser heating. As heat generation source, 0.8 mol% NiO was added to absorb continuous-wave laser with λ=1064 nm. After acid leaching, borate phase with NiO was remaining partially in laser irradiated area. Smooth, non-porous surface was found at cross section of laser irradiated area below surface, and nano-scale porous structure was found at non-irradiated area observed by scanning electron microscopy (SEM). X-ray Absorption Fine Structure (XAFS) spectra revealed that Ni2+ in laser irradiated area showed coordination change from 6 coordinated octahedral to 5 coordinated in square pyramid along with apparent color change from green to brown. Similar change was observed in water-quenched specimen from 1000°C. Ni2+ transition gave additional structural information in phase separate / homogeneous glass, which was difficult to be distinguished by spectroscopy which focuses on covalent bonding of glass network. [ABSTRACT FROM AUTHOR]

Preparation and application of glass spheres as resonators are discussed. Surface-tension mold (StM) and localized-laser heating (LLH) techniques have been developed to fabricate glass super spheres and true spheres, respectively. These prepared glass spherical particles have been examined to evaluate their suitability for whispering gallery mode (WGM) oscillators or laser cavities. Super spherical glass acts as a WGM oscillator using its equatorial plane. An equatorial circle roundness > 0.99 provides a high Q-value to lead laser oscillation. LLH demonstrates its excellent capability to prepare "true spheres" on a transparent substrate under gravity. A tellurite glass sphere prepared by the LLH technique exhibits a few-mW-order threshold for lasing at the 1.06-µm region. An added-on terrace and an installed bubble in the sphere serve as an input/output gate and as a "non-WGM" coupling input gate for laser action, respectively. Glass is showed to have strong potential with respect to both preparation and utilization of spherical shapes for optics. [ABSTRACT FROM AUTHOR]

Local surface plasmon resonance occurs depending on the size and morphology of noble metal nanoparticles. This study investigated the identification of spinous morphology of star-shaped Au–Ag nanoparticles by using discrete dipole approximation and morphological symmetric consideration. Star-shaped Au–Ag nanoparticles were prepared by adding ascorbic acid into a mixed solution of gold chloride and silver nitrate. By varying the Au/Ag ratio, nanoparticles with different aspect ratios and number of spines were obtained. Morphology was identified by comparing the optical absorption spectra of the nanoparticles with the absorption efficiency calculated from discrete dipole approximation based on the symmetry of decahedrons, dodecahedrons and icosahedrons. By considering the particle size distribution of the nanoparticles, the calculation accuracy was improved. In conclusion, this study demonstrated the potential of computational morphological identification in predicting nanoparticle with complexed morphology. [ABSTRACT FROM AUTHOR]

Abstract: Fine glass particles Na2O–CaO–B2O3–SiO2 are heated on glassy-carbon substrate to obtain micrometer-size solid immersion lenses (μ-SILs), and the composition dependence of the wetting property between glass melt and glassy-carbon substrate is investigated. The obtained glass particles have the super-spherical shapes with smooth surfaces. The contact angles of the particles are ranging from 125° to 147° depending on the glass composition, and there are the compositions at which the shape of the glass satisfies the optical condition of μ-SIL, showing the correlation between the contact angle and the internal structure of the glass. These results revealed that the super-spherical shape of μ-SIL can be controlled by the glass composition through the wetting property. [Copyright &y& Elsevier]

Abstract: A surface-tension mold technique that makes use of the wetting properties between glass melt and a substrate is used to fabricate micrometer-sized solid immersion lens from a high-refractive-index glass. Solid immersion lens can be used to overcome the optical diffraction limit. In this study, glass particles made from two different glasses (n =1.718 and 1.786) were melted on glassy-carbon substrates having optical-grade surfaces and cooled to room temperature. The optimum conditions for producing a super-spherical shape (i.e., a truncated sphere) while avoiding the crystallization of glass were obtained. The produced glass particles exhibited high transparency and super-spherical shape with smooth surfaces. The variations in the lens thickness and sphericity are submicron or less. Optical lens systems specially designed for these super-spherical lenses are expected to be capable of achieving resolutions that are 2.0 times higher than those attainable with conventional optical systems. [Copyright &y& Elsevier]

• Free-standing ultra-thin tellurite glass film was formed by glassblowing method. • The thickness of the film became uniform at high temperature. • The film with uniform thickness had TeO 2 - and B 2 O 3 -rich surface. This study investigates the thickness stabilization role of molten glass in the stable formation of tellurite glass film with submicron thickness. A tellurite glass balloon was formed by the glassblowing technique, then cooled to room temperature and cut into freestanding tellurite glass films. The fabrication conditions—blowing temperature, volume of introduced air, and inner pressure—were optimized for forming submicron-thick glass films with dimensions of 16 cm × 5 cm. The thickness reduced with increasing balloon size at 450 and 500°C, and was independent of the balloon size at 550°C. The formation mechanism of the tellurite glass film is apparently related to the surface tension gradient, which causes a compositional and structural change on the outermost surface of the molten glass. The tellurite films are potentially applicable as optical waveguides in next-generation optical circuits. [ABSTRACT FROM AUTHOR]

• Aluminosilicate glasses containing Ni were studied by spectroscopic techniques. • The proportion of [4]Ni2+ was quantified from optical absorption spectra. • Coordination of Ni2+ strongly depends on optical basicity or cation field strength. • Ni–O distance obtained from EXAFS was correlated with coordination number of Ni2+. • Ni2+ probes the local structure of Mg2+ in glass. We use Ni ions as a structural probe to investigate the influence of modifier cations (Na, K, Mg, Ca, and Ba) on the structure of aluminosilicate glasses. The color of these glasses varies with the nature of the cations present in glass. Structural origin of this change is investigated by optical absorption and X-ray absorption spectroscopies. Our results reveal pronounced changes in Ni coordination. Tetrahedra Ni2+ is present in all these glasses and Ni2+ in 5-fold coordinated site also appears. There is a weak contribution from octahedral Ni2+. The concentration of tetrahedral Ni2+ deduced from the optical absorption spectroscopy increases with decreasing CFS, explaining the variation of color from yellow and brown to purple. This is in line with X-ray absorption spectroscopy data. Cation-oxygen distances and site symmetry indicate a similar structural behavior of Mg2+ and Ni2+, being a good structural probe of Mg. [ABSTRACT FROM AUTHOR]

We present the results of force field molecular dynamics simulations of calcium aluminosilicate, sodium aluminosilicate, calcium silicate, and sodium silicate liquids under temperature gradient conditions. Non-equilibrium molecular dynamics simulations of these liquids under temperature gradient conditions reproduced the trend reported for Soret coefficients, with network-forming cations having larger coefficients compared with network-modifying ones. We found a linear relationship between the Soret coefficients and the variance of the potential energy distribution of each cation, which corresponds to the activation energy of diffusion. The Soret coefficients of sodium aluminosilicate liquids show a somewhat different behavior compared with that of the other liquids. This behavior could be explained by charge compensation of fourfold-coordinated aluminum species by sodium cations. Further studies of a larger variety of systems will reveal the full details of the relationship between Soret coefficients and microscopic structure/energy distribution, and enable us to estimate the Soret coefficients. [ABSTRACT FROM AUTHOR]

Understanding the molecular genetic basis of animal magnet reception has been one of the big challenges in molecular biology. Recently it was discovered that the magnetic sense of Drosophila melanogaster is mediated by the ultraviolet (UV)‐A/blue light photoreceptor cryptochrome (Cry). Here, using the fruit fly as a magnet‐receptive model organism, we show that the magnetic field exposure (0.4–0.6 mT) extended lifespan under starvation, but not in cryptochrome mutant flies (cryb). The magnetic field exposure increases motor function in wild type and neurodegenerative disease model flies. Furthermore, the magnetic field exposure improved sleep quality at night‐time specific manner, but not in cryb. We also showed that repeated AC magnetic field exposure increased climbing activity in wild‐type Drosophila, but not in cryb. The data suggests that magnetic field‐dependent improvement of lifespan, sleep quality, and motor function is mediated through a cry‐dependent pathway in Drosophila. [ABSTRACT FROM AUTHOR]

• A mist spin spray method was developed to fabricate nanostructured CuO thin films. • CuO thin films without impurities were fabricated at a low temperature of 90 °C. • The resulting CuO thin films showed sufficiently strong adhesion to substrates. • The film morphology could be modified by changing the precursor solutions. • Higher optical band gaps corresponded to smaller grain sizes in the films. A solution-based process, termed the mist spin spray method, was developed to fabricate nanostructured CuO thin films on seed-free glass substrates. In this method, a copper amine complex solution and a NaOH solution are separately atomized by ultrasonication to generate mists. These mists are subsequently sprayed onto a substrate heated to 90 °C and fixed on a rotating platform to grow crystalline CuO thin films at atmospheric pressure. This one-step method enables the generation of phase-pure, dense and crack-free CuO thin films below 100 °C. CuO thin films approximately 30 nm in thickness exhibited good adhesion to glass substrates, and the concentrations of NH 3 and NaOH in the initial solutions were found to affect both the film morphology and optical band gap. Specimens prepared using higher NH 3 and NaOH concentrations had larger grain sizes, while those fabricated using a low NaOH concentration showed a porous structure. A higher optical band gap was found to correlate with smaller grain sizes in the films. [ABSTRACT FROM AUTHOR]

A transparent ZnO film was deposited by the spin-spray method at a low temperature of 90 °C. Ultraviolet (UV) light irradiation to the film for 60 min decreased the film resistivity drastically by three orders of magnitude from 55.3 to 4.43 × 10−2 Ω cm. Time-of-flight secondary ion mass spectrometry (TOF-SIMS) depth profile and 1H solid-state nuclear magnetic resonance (NMR) spectroscopy analysis revealed that the as-deposited ZnO film before UV treatment contained a large amount of water in the ZnO crystal lattice, and hydrogen donors, including interstitial hydrogen in bond-centered sites ( H i ), substitutional hydrogen on the oxygen lattice site ( H O ), and three O–H bonds in a zinc vacancy ( V Z n − H 3 ), were generated in the ZnO film after UV treatment. From these results, the mechanism of the hydrogen donor formation was proposed in which UV irradiation to photocatalytic ZnO decomposed the water in the ZnO crystal lattice to form H+ and OH− ions, which associated with the oxygen and zinc vacancies, resulting in the formation of H i , H O , and V Z n − H 3 . [ABSTRACT FROM AUTHOR]

Photon emission (PE) at wavelength ranges of 430–490 nm (B-PE), 500–600 nm (G-PE) and 610–680 nm (R-PE) caused by brittle fracture was simultaneously measured in the nanosecond-to-microsecond and millisecond time domains for two types of borosilicate glasses: Pyrex-type Tempax glass and BK7 glass. The results were compared to those for silica and soda lime glasses. The time dependence of the PE of Tempax glass was similar to that of silica glass, while the PE intensity was lower. Because Tempax glass contains both silica-rich and borate-rich amorphous phases, the PE must be mainly produced by the fracture of the silica-rich phase. Moreover, the proportion of B-PE of Tempax glass was higher than that of silica glass. This suggests that the measured B-PE might also include very weak PE caused by the fracture of the borate-rich phase. The PE time dependence of BK7 glass was similar to that of soda lime glass, which was different from the case for Tempax glass. The PE intensity of BK7 glass was slightly higher than that of soda lime glass, but much lower than that of Tempax glass. The result indicates that non-bridging oxygen in the glasses affects crack propagation behavior and reduces the PE. [ABSTRACT FROM AUTHOR]

The laser manipulation of metal spheres in glass has been reported in the present work. Formation of a stainless steel-silver core–shell sphere in the glass has been demonstrated by passing a stainless steel sphere through silver-doped borosilicate glass. Silver-doped glass was obtained using a field-enhanced ion-exchange technique. The sodium ions in the neighborhood of the surface were exchanged with silver ions. A stainless steel sphere was passed through the silver-doped area, silver in the glass got concentrated in the sphere, and a core–shell stainless steel-silver sphere was formed. In the trajectory of the metal sphere migration, the amount of silver decreased, and silver particles were observed. The amounts of silver in the core–shell sphere and that eliminated from the glass, along the trajectory of the migrated metal sphere, were compared. This technique of laser-induced migration in silver-doped glass enables the formation of core–shell-structured metal spheres with the elimination of the silver contained in the glass along the migration trajectory of the sphere. [ABSTRACT FROM AUTHOR]

Surface structures of iron-phosphate glasses were examined using X-ray photoelectron spectroscopy ( XPS). Cr2O3, CoO, and Al2O3 were introduced to the glass by the replacement of a part of Fe2O3, and the simulated fission products are also added. The obtained glasses showed high chemical durabilities by MCC-1 test. In situ high-temperature and room-temperature XPS measurements were conducted on the polished sample surfaces and also those after 1-week chemical durability test. Unique trends were observed in XPS spectra on heating and after the chemical durability test, respectively. Nature of the glass surface of iron-phosphate glasses was explained from the point of view of surface energy, and the origin of high chemical durability and the effect of chromium ions were discussed based on the changes on surface composition and valence states of transition-metal ions. [ABSTRACT FROM AUTHOR]

• The structure of glass can be locally modified via platinum sphere migration. • Platinum nanoparticles were precipitated in the trajectories at low migration speeds. • The fictive temperature of glass increases with the migration velocity. In this study, metal spheres in glass were manipulated via heating using continuous-wave laser illumination. Metals are doped into the trajectory and selective compositional changes in the glass are observed. Meanwhile, the glass structure is modified via rapid heating and quenching. The structure of silica glass modified via platinum sphere migration was examined. Results of electron probe microanalysis confirm the presence of platinum in all trajectories, regardless of its low reactivity with silica glass. Elemental analysis reveals the precipitation of platinum nanoparticles in the trajectories at low migration speeds. Raman and infrared spectrum analyses reveal an increase in the fictive temperature, which increases with the migration velocity. Further, the etching rate increases with the sphere velocity. This study demonstrates that the structure of glass can be locally modified via platinum sphere migration, which depends on the sphere migration velocity. [ABSTRACT FROM AUTHOR]

Er3+/Dy3+ co-doped double-clad ZBLAN optical fiber has been used to obtain amplified spontaneous emission (ASE) broadband light sources cladding-pumped by 980-nm multimode laser diode (LD) sources. It has been demonstrated that mid-infrared broadband emission extending from 2515 to 3735 nm was obtained by energy transfer between Er3+ and Dy3+. We experimentally investigated the optimum design of Er3+/Dy3+ co-doped ZBLAN fiber in terms of ion concentration, fiber length, pumping configuration, and pumping power. The ASE output power was more than 2.5 mW when the LD pump power was set at 5 W. To assess its potential for gas sensing applications, the fabricated ASE light source was used to successfully detect methane gas with concentrations at 1% and 5%. The simple and stable construction of our ASE light source is suitable for practical purposes. [ABSTRACT FROM AUTHOR]

The spin-spray technique was used to fabricate phase-pure Cu 2 O films at 70 °C with a high deposition rate of 0.3 μm/min. The source solution, containing a mixture of CuSO 4 ･5H 2 O and l -ascorbic acid, and the reaction solution, containing NH 3 and NaOH, were sprayed on the rotating substrates. It was possible to control the grain size, the crystalline orientation of the films, the surface morphology, and the optical band gap by adjusting the concentrations of NH 3 and NaOH in the reaction solution. The films fabricated with a low NH 3 aq. concentration were composed of nanosized grains and highly [111] oriented. On the other hand, films fabricated with a high NH 3 aq. concentration were composed of submicron grains and highly [100] oriented. The surface morphologies of the films varied according to the concentration of NaOH. The surface of the films fabricated with a low NaOH concentration were almost flat and had a {100} orientation on their surface. On the other hand, films fabricated with a high NaOH concentration were composed of pyramidal grains. A smaller grain size in the films corresponded with a higher optical band gap. Image 1092740 • The spin-spray technique enabled the fabrication of phase-pure Cu 2 O films at 70 °C. • Cu 2 O films were fabricated with a high deposition rate of 0.3 μm/min. • The fabricated Cu 2 O films had strong adhesion to the substrates. • It was possible to control the morphology of Cu 2 O films via solution conditions. • The smaller grain size in the films corresponded to a higher optical band gap. A novel solution processing technique referred to as the "spin-spray technique" enabled the fabrication of phase-pure Cu 2 O films at 70 °C with a high deposition rate of 0.3 μm/min on glass substrates. In this technique, two solutions are sprayed on to the substrates placed on a rotating disk heated to a temperature below 100 °C. Two kinds of mixed aqueous solutions were used in this study: one was an acid aqueous solution of CuSO 4 ･5H 2 O and l -ascorbic acid, referred to as the source solution; the second was a strongly alkaline aqueous solution of NaOH and NH 3 , referred to as the reaction solution. Because Cu+ is less stable than Cu2+ in aqueous solutions, the preparation of phase-pure Cu 2 O is very difficult via solution processing. Since l -ascorbic acid can efficiently reduce copper ions in the acidic source solution, unstable Cu+ could be supplied to the reaction site stably. Furthermore, the sprayed reaction solution provided an alkaline environment to the site, which was necessary to precipitate Cu 2 O crystals. While NaOH promoted the nucleation of Cu 2 O crystals, NH 3 suppressed their homogeneous nucleation by forming a copper ammine complex. As a result, heterogeneous nucleation occurred on the substrates and Cu 2 O films could be formed. It was possible to control the grain size, the crystalline orientation, and the surface morphology of the films by adjusting the concentrations of NaOH and NH 3 in the reaction solution. The surfaces of the films fabricated with a lower NaOH concentration were composed of flat grains. The films fabricated with a low NH 3 aq. concentration were composed of nanosized grains and highly [111] oriented. In contrast, films fabricated with a high NH 3 aq. concentration were composed of submicron grains and highly [100] oriented. The smaller grain size in the films corresponded to a higher optical band gap. [ABSTRACT FROM AUTHOR]

Transparent zinc oxide (ZnO) films that were prepared via a spin-spray process using sodium citrate as a surfactant were exposed to UV light of varying wavelengths and irradiation times. The effects of the UV irradiation on the optical and electrical properties of the ZnO films were examined. The band gap of the as-prepared ZnO film (3.46 eV) increased after UV irradiation, even when exposed to relatively long wavelengths (>365 nm) with a low power density (~0.55 W/cm2). The modifications in the band gap and conductivity of the spin-sprayed ZnO films were primarily caused by the persistent photo-conductivity effect and photodecomposition-induced doping. Examination of the ZnO films using FTIR indicated that irradiation with shorter UV wavelengths (≤350 nm) improved the photodecomposition of carbon impurities that were inside the ZnO films, which resulted in enhanced conductivity and electrical stability for >1 days. Unlabelled Image • Electrical and optical properties of ZnO films were modified by UV irradiation. • Band gap of ZnO films was varied with the wavelength of UV treatment and duration of dark storage. • ZnO films treated by UV (≤365 nm) reveal better conductivity and electrical stability. [ABSTRACT FROM AUTHOR]

Laser illumination on a nickel sphere in silica glass has shown to migrate the sphere towards the light source with a nickel nanoparticle precipitated around the sphere. The selective nanoparticle precipitation by Invar 42 sphere migration in silica glass is reported. An Invar sphere is implanted into glass by laser illumination of an Invar foil. In addition to the sphere migration in glass, stripes are formed along the trajectory of the sphere. The stripes consist of metal nanoparticles with a diameter of several hundred nanometres. Nanoparticles precipitated on the laser-illuminated side are composed only of nickel and those on the non-illuminated side are composed of nickel and iron alloys. The reason for the difference in components is discussed. [ABSTRACT FROM AUTHOR]

• Nickel sphere migration in glass ceramics eliminated phosphorus and tin. • Eliminated phosphorus and tin were condensed in the nickel sphere. • Nickel was doped in the trajectory of the sphere migration. Changes in the local composition of glass, which can locally control the optical properties of glass, are used to form optical waveguide materials, such as optical fibers. The authors have previously demonstrated the technique of metal sphere manipulation inside glass. In this method, the metal sphere moves toward a laser light source, absorbing the light and making the glass soft in the vicinity. In this paper, we report that the nickel sphere migration in glass ceramics dedoped phosphorus and tin from the trajectory of the sphere migration and condensed them in the nickel sphere. At the same time, nickel was doped in the trajectory of nickel sphere migration. The mechanisms of dedoping and incorporation are presented. [ABSTRACT FROM AUTHOR]

[Display omitted] • CuO nanostructures were fabricated on flexible substrates via spin-spray method. • Grass-like CuO nanosheets array structure were fabricated with ethylenediamine. • CuO nanosheets array structure possessed excellent humidity sensing performance. • CuO nanosheets array-based sensor had high stability and durability against bending. Carpet-like and grass-like arranged CuO nanosheets were fabricated on flexible polyethylene terephthalate substrates via the spin-spray method using different complexing agents. The CuO nanostructures strongly adhered to the substrate, and the resulting coated substrates were sufficiently flexible to be used as humidity sensors in a bent state. The humidity-sensing properties were evaluated by exposing the sensors to 20–90% relative humidity at room temperature. The sensor based on the carpet-like CuO nanosheets did not exhibit any humidity response. The grass-like CuO nanosheets had excellent humidity-sensing performance as evidenced by the linear resistance behavior, short response and recovery times of 2.1 s and 2.8 s, respectively, and high sensitivity of up to 170%. In addition, the sensor based on the nanosheets possessed high stability and durability against mechanical bending. The sensitivity and response and recovery times were almost unchanged even when the bending angle was 90° and after 1000 bending-relaxation cycles. [ABSTRACT FROM AUTHOR]

αFe 2 O 3 and binary composite Cu 2−x O-αFe 2 O 3 films were deposited onto fluorine-doped tin oxide glass via a spin spray process at 90 °C. Composite films of varying composition such as αFe 2 O 3 (FC-0), CuO-αFe 2 O 3 (FC-1) and Cu 2 O-αFe 2 O 3 (FC-2) were prepared by controlling the ion molar ratio of the precursor source solution. The FC-0 surface exhibited poor wetting traits toward water (θ c > 90°). Conversely, the FC-2 surface displayed good wettability, exhibiting a water contact angle <10°. When serving as supercapacitor electrodes, the obtained FC-0, FC-1 and FC-2 electrodes demonstrated a wide negative potential window of −0.9 V to 0 V vs Ag/AgCl in a 0.5 M aqueous Na 2 SO 4 solution. The supercapacitor comprising the FC-2 electrode exhibited an area normalized capacitance of 182.4 mF cm−2 at 0.5 mA cm−2, which is ∼23.4 times greater than the corresponding FC-0 electrode (7.8 mF cm−2 at 0.5 mA cm−2). Furthermore, the FC-2 supercapacitor demonstrated a capacitance retention of 92%, which suggests good long-term cycling stability. This study indicates that the spin-sprayed Cu 2−x O-Fe 2 O 3 composites are promising candidates for high performance supercapacitor electrode materials. [ABSTRACT FROM AUTHOR]

Light is able to remotely move matter. Among various driving forces, laser-induced metal sphere migration in glass has been reported. The temperature on the laser-illuminated side of the sphere was higher than that on the non-illuminated side. This temperature gradient caused non-uniformity in the interfacial tension between the glass and the melted metal as the tension decreased with increasing temperature. In the present study, we investigated laser-induced metal sphere migration in different glasses using thermal flow calculations, considering the temperature dependence of the material parameters. In addition, the velocity of the glass flow generated by the metal sphere migration was measured and compared with thermal flow calculations. The migration velocity of the stainless steel sphere increased with increasing laser power density; the maximum velocity was 104 μm/s in borosilicate glass and 47 μm/s in silica glass. The sphere was heated to more than 2000 K. The temperature gradient of the interfacial tension between the stainless steel sphere and the glass was calculated to be −2.29 × 10−5 N/m/K for borosilicate glass and −2.06 × 10−5 N/m/K for silica glass. Glass flowed in the region 15-30 μm from the surface of the sphere, and the 80-μm sphere migrated in a narrow softened channel. [ABSTRACT FROM AUTHOR]