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This paper presents a facile method to fabricate nanostructured copper-oxide (Cu2O/CuO) electrodes with columnar morphology for non-enzymatic glucose sensing. The electrodes were fabricated using a two-step method; first by producing Cu nanostructures through glancing angle deposition (GLAD), followed by a thermal annealing process at various temperatures. The nanostructures were characterized by X-ray diffraction and scanning electron microscopy to evaluate their structural and morphological properties. The optical properties of the electrodes were also investigated by VIS/NIR spectroscopy. Electrochemical characterization revealed that Cu2O outperformed other copper-based nanostructures, with the best sensitivity of 1394 μAcm-2 mM-1 and the lowest limit of detection (LOD) of 0.052 μM. The superior sensor also exhibits two broad linear ranges of 0.01–2 mM and 2–5 mM at the optimized potential of 0.6 V. The Cu2O electrodes demonstrate the merits of reproducibility, selectivity, fast response time, and high accuracy in measuring glucose levels in real blood serum samples.

Present work reports the growth of BFO/WO3 bilayer thin film structures over Silicon, corning and ITO coated glass substrates. BFO layer in BFO/WO3 bilayer structure was deposited using Pulsed Laser deposition (PLD) technique at optimized laser energy (200 mJ) while WO3 nanostructured layer was deposited using rf‐magnetron sputtering technique at varying glancing angle from 65° to 80°. For the realization of MBM (metal‐bilayer‐metal) device, top Gold (Au) electrodes have been deposited using thermal evaporation technique. The BFO/WO3 bilayer structure fabricated at 70° glancing angle exhibited the saturation (Ps) and remnant (Pr) polarization as 45.45 μC/cm2 and 21.52 μC/cm2 respectively, which are appreciably higher than the earlier reports for pure BFO thin films. Enhanced energy storage characteristics were obtained in Au/BFO/WO3/ITO structure fabricated at 70° glancing angle with charge‐discharge efficiency (63%) and enlarged recoverable energy density (467 mJ/cm3). Achieved results indicate the utilization of fabricated Au/BFO/WO3/ITO structures towards high energy storage applications. [ABSTRACT FROM AUTHOR]

In practical applications, the current ocean internal wave detection technology has large errors, and is significantly affected by the marine environment, and cannot be identified independently. In view of these problems, this study proposes a monitoring method for ocean internal wave early warning based on vector field processing. This method is based on the combined information processing of sound pressure and vibration velocity, and uses the three-dimensional information of the sound field picked up by the ultra-low frequency vector hydrophone. The time-space-frequency three-dimensional tracking and locking of non-cooperative targets can be carried out in the complex ocean background noise field according to the azimuth estimation algorithm. The arrival of internal wave causes the change of the three-dimensional sound velocity profile. The fluctuation of the sound field will lead to the change of the acoustic energy flow intensity of the target signal source. This method realizes the monitoring and prediction of ocean internal waves based on the abnormal jump of the vertical grazing angle caused by the channel distortion of the target signal in the internal wave space. The simulation results show that the vertical grazing angle fluctuates slightly in a normal environment, and the range of change is small. When the internal wave strikes, the grazing angle changes strongly, and the maximum deflection can be abruptly changed to a negative angle, which proves the effectiveness of the method. [ABSTRACT FROM AUTHOR]

SnSe single crystals have been demonstrated to possess excellent thermoelectric properties. In this work, we demonstrate a grain size control method in growing nanocrystalline SnSe thin films through a glancing angle pulsed-laser deposition approach. Structural characterization reveals that the SnSe film deposited at a normal angle has a preferred orientation along a axis, while by contrast, the SnSe film deposited at an 80° glancing angle develops a nanopillar structure with the growth direction towards the incident atomic flux. The glancing angle deposition greatly reduces the grain size of the thin film due to a shadowing effect to the adatoms, resulting in significantly increased power factor for more than 100%. The maximum Seebeck coefficient and power factor are 498.5μV/K and 18.5μWcm−1K−2, respectively. The enhancement of thermoelectric property can be attributed to the potential barrier scattering at grain boundaries owing to the reduced grain size and increased grain boundaries in the film. Given this enhanced power factor, and considering the fact that the nanopillar structure should have much lower thermal conductivity than a plain film, the zT value of such made SnSe film could be significantly larger than the corresponding single crystal film, making it a good candidate for thin film-based thermoelectric device.

Transparent polycrystalline TiO2 thin films have been deposited on unheated glass substrates using RF reactive magnetron sputtering. Depositions were carried out at different glancing angles and with different total gas mixture pressures. The variation of these parameters affected the crystal phase composition and the surface morphology. Depending on the glancing angle and the pressure, rutile, mixed anatase/ rutile and pure anatase were deposited at low substrate temperature. Both hydrophilic and hydrophobic TiO2 were obtained, exhibiting fast photoconversion to superhydrophilic upon UV irradiation. The effect of the materials physicochemical properties on the wettability and rate of the UV induced superhydrophilicity is evaluated.

Zr-Co-RE non-evaporable getter films have excellent gas adsorption performance therefore can be used in vacuum sealed electronic devices. The microstructure of getter films has vital effect on adsorption performance. In this paper, Zr-Co-RE films deposited by DC magnetron sputtering at different glancing angles are investigated including microstructures and adsorption characteristics. The surface and cross-sectional morphologies demonstrate loose, porous and columnar-like structure which forms because of low lateral mobility of Zr and Co atoms and shadowing effect of non-perpendicular sputtering. Zr-Co-RE films are amorphous or nanocrystalline structure. The films deposited at 90° glancing angle show large grain size. After Zr-Co-RE films are heated at 350 °C for 15 min, the H _2 adsorption capacity and pumping speed at ambient temperature are tested. The films grown at 90° glancing angle have highest initial pumping speed (103.9 ml s ^−1 cm ^−2 ), which owe to its more gas diffusion path and active surface, meanwhile, the adsorption capacity is lower than 60° because of difficult and limited diffusion process into getter matrix. The films grown at 60° glancing angle have best adsorption capacity (71.5 Pa.ml cm ^−2 ) and pumping speed stability.

This paper reports on the discovery of ambiguity in the traditional definitions of the ‘Angle of diffraction’ in Physical/Wave optics and ‘Glancing angle’ in X-ray crystallography. Just like the 2005 discovery by the author regarding the ambiguity in the traditional definitions of angles of incidence, reflection and refraction, the traditional definitions of the aforesaid two angles have also been found to be ambiguous. The long-running definition of angle of diffraction in Physical/Wave optics does not have any parity with the definitions of angles of incidence, reflection, and refraction in Geometrical optics, in each of which the direction of the positive unit normal to the reflecting surface (surface of discontinuity) at the point of incidence is one of the two directions to be considered in defining the angle. Similarly the traditional definition of the Glancing/Grazing angle in X-ray crystallography is in conflict with the fundamental definition of angle in geometry. With a view to getting rid of the ambiguity present in the traditional definitions of ‘Angle of diffraction’ and ‘Glancing/Grazing angle’, as well as to enhance and sophisticate the relevant field of study, unambiguous definitions of both these two angles have been offered in this paper. [ABSTRACT FROM AUTHOR]

Crystalline TiO2 films were prepared on unheated glass substrates by radio frequency (RF) reactive magnetron sputtering at normal angle of incidence (a = 0°) and at glancing angle (a = 87°). The effect of the glancing angle on the structure, microstructure, and wetting properties of the films was investigated. The inclination of the substrate led to phase transformation of the deposited films from rutile to either rutile/anatase or anatase, depending on the working pressure. Extreme shadowing at 87° results in a remarkable increase of the films’ porosity and surface roughness. The mechanism of the glancing-angle-induced crystalline phase formation is thoroughly discussed based on the thermodynamic, kinetic, and geometrical aspects of the nucleation and is related with the microstructural changes. Both crystalline phase and microstructure significantly affect the wetting properties of the TiO2 films. Glancing-angle-deposited anatase TiO2 exhibits a high degree of porosity and roughness, a high rate of UV-induced wettability conversion, and a long-term highly hydrophilic nature in dark. Therefore, anatase TiO2 is potentially a good candidate for applications as dye-sensitized solar cells (DSSC)/perovskite solar cells, microfluidic devices, and self-cleaning surfaces prepared on thermosensitive substrates.

AbstractThere is intense and growing interest in one-dimensional (1-D) nanostructures from the perspective of their synthesis and unique properties, especially with respect to their excellent optical response and an ability to form heterostructures. This review discusses alternative approaches to preparation and organization of such structures, and their potential properties. In particular, molecular-scale printing is highlighted as a method for creating organized pre-cursor structure for locating nanowires, as well as vapor–liquid–solid (VLS) templated growth using nano-channel alumina (NCA), and deposition of 1-D structures with glancing angle deposition (GLAD). As regards novel optical properties, we discuss as an example, finite size photonic crystal cavity structures formed from such nanostructure arrays possessing highQand small mode volume, and being ideal for developing future nanolasers.

Abstract: Recent experimental sputtering yield data for Si sputtered by 30keVGa FIB shows a discrepancy with binary collision (BC) simulations for angles greater than 85°. This study investigates the factors of BC simulations that could be responsible for the discrepancy at glancing angles, including surface roughness, Ga implantation, electronic stopping, and surface binding energy. It is concluded that the dominant factor at glancing angles is surface roughness. Two roughness models, sinusoidal and pink noise, are used to demonstrate that very small amplitude (∼2Å) roughness is required to obtain quantitative agreement with experiments at very glancing angles. Furthermore, it is shown that large amplitude roughness should be unstable under glancing angle beams. [Copyright &y& Elsevier]

Abstract: The effect of activation temperature on the degree of reduction of dense and porous TiZrV films was investigated by synchrotron radiation photoemission spectroscopy. The dense and porous TiZrV films have similar composition and thickness, and their specific surface areas are 2 m2/g and 13 m2/g, respectively. Comparing the previous results of the porous TiZrV film [Chien-Cheng Li, Jow-Lay Huang, Ran-Jin Lin, Chia-Hao Chen, Ding-Fwu Lii, Thin Solid Films 515, (2006) 1121.], the degree of activation of the porous TiZrV film is lower than that of the dense TiZrV film. To complete the activation treatment of the dense and porous TiZrV films, the activation temperature must be higher than 350 °C or the activation time must be longer than 30 min. [Copyright &y& Elsevier]

Abstract: TiZrV films, grown at the deposition angles of 0° and 70°, were used for the study of the oxygen-adsorption process. When the deposition angle is 0°, the appearance of the film is dense columnar structure. However, the film grown at the glancing angle of 70° is composed of porous and isolated columns, which are made of fine clusters. The activated TiZrV films have the capability to absorb oxygen at room temperature. The component Zr is more easily oxidized than Ti and V components when the TiZrV film is exposed in oxygen. The content of oxidized Ti and oxidized V does not linearly increase with the increase of oxygen exposure when there is a metallic Zr component on the surface of the film. [Copyright &y& Elsevier]

Abstract: Angular distributions of 380keV protons reflected from (111) surface of Si monocrystal were measured in the range of projectiles glancing angle from 0.3° up to 0.8°. It is shown that increase of glancing angle causes non-linear change of such distribution parameters as angular width of the front rise, angular width of the distribution, the maximum yield value. Registered energy spectrum of reflected particles for glancing angle of 0.5° consists of several peaks with practically constant angular intervals between them and maxima weakly reducing towards lower energy region. It is experimentally shown that the most energetic peak relates to the reflection from the very surface and the rest ones are caused by successive scattering of ions by inner silicon crystallographic planes. [Copyright &y& Elsevier]

Abstract: Highly porous TiZrV film getters on (100) silicon substrates have been successfully grown by the glancing angle dc magnetron sputtering method. The glancing angle is defined as the angle between the surface normal to the substrate and the surface normal to the target. The main deposition parameters that produce the porous TiZrV films are the pressure of sputtering gas Ar and glancing angle at room temperature. The larger the glancing angle is, the higher the porosity and specific surface area of the TiZrV films are. The specific surface area of the dense and porous TiZrV films is 2 m2/g and 13 m2/g, respectively. The diameter of columnar width and inter-distance between the columnar crystals of the porous film are 200 nm and 50 nm, respectively. The columnar width of dense TiZrV films is about 100 nm. The porous TiZrV films have a larger capability to absorb oxygen than that of the dense TiZrV films. [Copyright &y& Elsevier]

Abstract: Highly porous Ti and TiZrV film getters on (100) silicon substrates, grown by the glancing angle deposition of dc magnetron sputtering method, were used to study the activation process. The effect of activation temperature on the reducing degree of the porous Ti and TiZrV films were investigated by synchrotron radiation photoemission spectroscopy (SRPES). Elemental carbon absorbed on the surface of the Ti film, exposed in air, will be transformed to a Ti carbide phase, however, that which is on the surface of the TiZrV film will be completely removed by heat at 250 °C or above. The oxidized Ti in a porous TiZrV film is more easily reduced than that in the porous Ti films. The breakdown of V–O and Ti–O bonds on the TiZrV film surface is easier than that of the Zr–O bond. We suggest that the decrease of reducing temperature of oxidized TiZrV, comparing with that of oxidized Ti, is caused by the displacement reaction of Zr on oxidized Ti or oxidized V. [Copyright &y& Elsevier]

Abstract: When fast electrons cross a solid surface, surface plasmons may be generated. Surface plasmon excitations induced by electrons moving in the vacuum are generally characterized by the surface excitation parameter. This parameter was calculated for 200–1000eV electrons crossing the surfaces of Au, Cu, Ag, Fe, Si, Ni, Pd, MgO and SiO2 with various crossing angles. Such calculations were performed based on the dielectric response theory for both incident (from vacuum to solid) and escaping (from solid to vacuum) electrons. Calculated results showed that the surface excitation parameter increased with crossing angle but decreased with electron energy. This was due to the longer time for electron–surface interaction by glancing incident or escaping electrons and by slow moving electrons. The results were fitted very well to a simple formula, i.e. , where P s is the surface excitation parameter, E is the electron energy, α is the angle between the electron trajectory and the surface normal, and a, b and c are material dependent constants. [Copyright &y& Elsevier]

Abstract: The porous Ti film getters on (100) silicon substrates were prepared using the glancing angle deposition of dc (direct current) magnetron sputtering method. The main deposition parameters that produce the porous Ti films are the low substrate temperature and high glancing angle. The larger the glancing angle is, the higher the porosity of the Ti films is. The porous films, grown at the glancing angle of 70° and room substrate temperature, are composed of nano-columnar crystalline crystals. The size and inter-distance between the columnar crystals are 70 nm and 30 nm, respectively. The porous Ti films have larger capability to absorb the oxygen than that of dense Ti films and Si substrate. The suitable operation condition of porous Ti film getters was also established. [Copyright &y& Elsevier]

Abstract: By using a portable total reflection X-ray fluorescence spectrometer with a 1 W X-ray tube, a specimen containing nanograms of Ca, Sc, Ti, V, Cr, Mn, Fe, and Ni is measured at several glancing angles of incident X-rays. Continuum X-rays are used as the excitation source. The intensities of the spectral background which degrades sensitivity to trace elements are decreased with a decrease of the glancing angle, and all these elements are detected at the glancing angle of 0.13° smaller than the critical angle for total reflection of the incident X-rays (0.20°). An optimum glancing angle for simultaneously detecting these trace elements is around 0.13°, and detection limits at 0.13° are sub-nanograms to ten nanograms. [Copyright &y& Elsevier]

Transparent polycrystalline TiO2 thin films have been deposited on unheated glass substrates using RF reactive magnetron sputtering. Depositions were carried out at different glancing angles and with different total gas mixture pressures. The variation of these parameters affected the crystal phase composition and the surface morphology. Depending on the glancing angle and the pressure, rutile, mixed anatase/ rutile and pure anatase were deposited at low substrate temperature. Both hydrophilic and hydrophobic TiO2 were obtained, exhibiting fast photoconversion to superhydrophilic upon UV irradiation. The effect of the materials physicochemical properties on the wettability and rate of the UV induced superhydrophilicity is evaluated. [ABSTRACT FROM AUTHOR]

Transparent polycrystalline TiO 2 thin films have been deposited on unheated glass substrates using RF reactive magnetron sputtering. Depositions were carried out at different glancing angles and with different total gas mixture pressures. The variation of these parameters affected the crystal phase composition and the surface morphology. Depending on the glancing angle and the pressure, rutile, mixed anatase/ rutile and pure anatase were deposited at low substrate temperature. Both hydrophilic and hydrophobic TiO 2 were obtained, exhibiting fast photoconversion to superhydrophilic upon UV irradiation. The effect of the materials physicochemical properties on the wettability and rate of the UV induced superhydrophilicity is evaluated.

Tungsten oxide thin films are prepared by glancing‐angle reactive magnetron sputtering at room temperature. The surface and cross‐section morphologies are characterized by FE‐SEM and TEM. The electrochromic properties of the thin films are studied using a three‐electrode system in 1 m LiClO4/PC solution. When the glancing angle is kept at 80°, a nanocolumnar structured film is obtained. This nanocolumnar structured film shows a lower driving potential and better stability compared to the dense film. The charge capacity per unit area of the nanocolumnar structured film is determined to be 30.85 mc cm−2. The diffusion rates of injection and detachment of ions are determined to be Din = 6.57 × 10−10 cm2 s−1 and Dde = 6.55 × 10−10 cm2 s−1 under an applied potential of ±1.2 V, respectively. The optical modulation amplitude of the nanocolumnar structured film reaches 65% at a wavelength of 600 nm and the optical density is superior to that of the dense film. [ABSTRACT FROM AUTHOR]

Crystalline TiO2 films were prepared on unheated glass substrates by radio frequency (RF) reactive magnetron sputtering at normal angle of incidence (a = 0°) and at glancing angle (a = 87°). The effect of the glancing angle on the structure, microstructure, and wetting properties of the films was investigated. The inclination of the substrate led to phase transformation of the deposited films from rutile to either rutile/anatase or anatase, depending on the working pressure. Extreme shadowing at 87° results in a remarkable increase of the films' porosity and surface roughness. The mechanism of the glancing-angle-induced crystalline phase formation is thoroughly discussed based on the thermodynamic, kinetic, and geometrical aspects of the nucleation and is related with the microstructural changes. Both crystalline phase and microstructure significantly affect the wetting properties of the TiO2 films. Glancing-angle-deposited anatase TiO2 exhibits a high degree of porosity and roughness, a high rate of UV-induced wettability conversion, and a long-term highly hydrophilic nature in dark. Therefore, anatase TiO2 is potentially a good candidate for applications as dye-sensitized solar cells (DSSC)/perovskite solar cells, microfluidic devices, and self-cleaning surfaces prepared on thermosensitive substrates. [ABSTRACT FROM AUTHOR]