Diffraction Angle Research Articles

Characterization of RF-Sputtered ZnO Thin Film Coatings on Aluminum (Al6061): Microstructure, Wettability, Cavitation, and Corrosion Analysis

The study focuses on the characterization of Aluminum (Al-6061) coated with RF-sputtered Zinc Oxide (ZnO) thin film, aiming to understand the complex interactions between microstructure, wettability, cavitation resistance, and corrosion performance. The study involves the use of various analytical techniques such as Field Emission Scanning Electron Microscopy (FESEM), energy-dispersive X-ray spectroscopy (EDS), X-ray diffraction (XRD), and water contact angle (WCA) measurements. The cavitation erosion testing has been conducted under various factors namely jet velocity (m/s), impingement angle (°), and stand-off distance (cm), respectively, and that too at various levels. Further, with the use of RSM, the study also contributes to the interplay in between factors and acquiring optimized results. Moreover, the findings of the study provide valuable insights into the effectiveness of the ZnO coating in enhancing corrosion resistance and reducing mass loss due to cavitation erosion. The study’s results offer significant implications for the engineering and design of protective coatings for Aluminum surfaces, with the potential to enhance durability and performance in various industrial applications.

Synthesis and Characterization of SiO2 Nanoparticles for Application as Nanoadsorbent to Clean Wastewater

By way of the sol–gel chemical synthesis method, it is possible to synthesize SiO2 nanoparticles with a defined specific particle size, a surface area, and a defined crystal structure that can be effectively used as a nanoadsorbent to remove various organic dyes. SiO2 nanoparticles were synthesized by the sol–gel method using sodium silicate (Na2SiO3) by a green method without using a tetraethyl orthosilicate (TEOS) precursor, which is very expensive and highly toxic. This sol–gel process involves the formation of a colloidal suspension (sol) and solid gelation to form a network in a continuous liquid phase (gel). In addition, it requires controlled atmospheres. XRD indicates the presence of an amorphous phase with a diffraction angle of 2θ = 23°, associated with SiO2. UV-Vis spectroscopy reveals an absorbance value in the region of 200 nm to 300 nm, associated with SiO2 nanoparticles. The application as a nanoadsorbent to remove dyes was measured, and it was found that the nanoparticles with the best performance were those that were synthesized with pH 7, showing a 97% removal with 20 mg of SiO2 nanoparticles in 60 min. Therefore, SiO2 nanoparticles can be used as a nanoadsorbent, using a low-cost and scalable method for application to remove methylene blue in an aqueous medium.

Synthesis methodology of pure N–A–S–H gels with wide range of Si/Al ratios at ambient temperature

AbstractThis study presents the development of a synthesis route for sodium aluminosilicate hydrate (N–A–S–H) gels with various Si/Al ratios carried out at ambient temperature. The synthesis is based on a simple “sol–gel” method, where commercial reactants are used to provide highly reactive Si and Al sources. Comprehensive characterization, including scanning electron microscope‐energy‐dispersive spectroscopy (SEM‐EDS), gas pycnometry, inductively coupled plasma (ICP), X‐ray photoelectron spectroscopy (XPS), thermogravimetric analysis (TGA), X‐ray diffraction (XRD), and magic angle spinning (MAS) nuclear magnetic resonance (NMR) (27Al, 23Na, 29Si, and 1H), is employed to verify the morphology, density, chemical composition, long‐range order, and local structure of the gels. Our results show that the synthesized gels are pure, amorphous, and homogeneous with Si/Al final ratio ranging from 1.22 to 2.23. Structural analysis of the gels indicates the synthesis of compounds with high degree of geopolymerization, which are representative of N–A–S–H gel formed in sodium‐based geopolymers.

New approach for deacidification and consolidation of bone artifacts

Acidic conditions affect the archaeological bone in the burial and in uncontrolled display and storage environment or due to improper restoration processes. Accordingly, bones become weak and fragile. This study aims to evaluate nano calcium propionate and nano styrene butyl acrylate (used for the first time in the treatment of bones) at different concentrations for deacidification and consolidation of fragile bones. New bone samples were prepared. Artificial accelerated aging (acid and heat) was applied to prepare aged untreated samples. Deacidification and consolidation processes using the materials mentioned above were applied. The analytical techniques used were transmission electron microscope (TEM) and thermal gravimetric analysis (TGA) were used for morphological and thermal stability investigation for the prepared nano styrene butyl acrylate copolymer and its calcium propionate nonocomposites, a digital microscope and scanning electron microscope (SEM) for investigation of the surface morphology, pH value measurement, change of color measurement, attenuated total reflection—Fourier transform infrared spectroscopy (ATR/FTIR), contact angle (wettability), and X-ray diffraction analysis for measurement of bone crystallinity. The results proved that acid-heat aging affected bone properties such as changes in surface morphology and color, decrease in pH value, and contact angle. Bone samples became more crystalline, and the chemical composition of bone was also affected. The treatment of aged untreated bone samples with the materials used in this study improved their properties, such as increasing the pH value and contact angle. The surface morphology, color change, and crystallinity of bone improved and became more stable.

Foam drainage agent with enhanced foam stability through modified Fe3O4 nanoparticles

A nanofoam drainage agent was developed to address the challenges of inadequate foam stability and foaming efficiency in the gas recovery process of foam drainage. The formulation of the primary foam drainage agent was obtained by screening and combining conventional anionic and amphoteric surfactants. Experimental results revealed a synergistic interaction between α-olefin sulfonate (AOS) and lauramidopropyl betaine (LAB-35). Specifically, when a mixture of 0.4 wt.% AOS and 0.1 wt.% LAB-35 was used, the surface tension of the primary foam drainage agent was measured to be 23.32 mN/m. Furthermore, modification of Fe3O4 nanoparticles with the silane coupling agent γ-(methacryloxy)propyl trimethoxysilane (KH-570) was performed to improve the dispersibility in aqueous solutions and enhance foam stability. The results of infrared spectroscopy, x-ray diffraction, thermogravimetric analysis, and contact angle measurements revealed the effective bonding of KH-570 to the surface of Fe3O4 nanoparticles. Additionally, the particle size distribution in the aqueous solution showed the excellent dispersion of the modified Fe3O4 nanoparticles. Through the incorporation of the modified Fe3O4 nanoparticles into the primary foam drainage agent, a nanofoam drainage agent with a half-life of 989 ± 6.5 s was developed. Microscopic observations of foam coarsening behavior revealed the mechanism behind foam stability. Performance testing of the foam drainage agent demonstrated the agent’s outstanding resistance against salinity, temperature, and oil and its remarkable liquid-carrying capacity.

Manipulation of Bloch surface beams based on perfectly matched Bragg diffraction

A generalized method is proposed for the manipulation of Bloch surface waves (BSWs) with multiple designed phases. This method is based on perfectly matched Bragg diffraction with a wide range of available diffraction angles and can be used beyond the paraxial limit to realize nonparaxial accelerating BSW beams. When combined with the caustic method, multiple accelerating beams with pre-engineered trajectories have been successfully generated, including power-law, circular, elliptic, and bottle beams. Furthermore, the transverse light field distribution of these accelerating beams is consistent with the theoretical prediction, indicating that the beam width can be manipulated by controlling the trajectory of the beam. The results of this work will facilitate the development of novel applications where controlling the trajectory and width of the two-dimensional beams is crucial, such as surface tweezers, and lab-on-chip photonic integrations.

WITHDRAWN: Metrology of warpage in silicon wafers using X-ray diffraction mapping

X-ray Diffraction (XRD) mapping is a non-destructive metrology technique that enables the reconstruction of warpage induced on a Silicon wafer through thermo-mechanical stress. Here, we mapped the wafer’s warpage using a methodology based on a series of line scans in the x and y directions and at different 90-degree rotations of the same sample. These line scans collect rocking curves from the wafer’s surface, recording the diffraction angle (ω) deviated from the Bragg angle due to surface misorientation. The surface warpage reflects in XRD measurements by inducing a difference between the measured diffraction angle and the reference Bragg angle (ω − ω0) and rocking curve broadening (FWHM) By collecting and integrating the rocking curves (RCs) and FWHM broadening from the whole surface and multiple rotations of the wafer, we could generate 3D maps of the surface function f(x) and the angular misorientation (warpage). The warpage exhibits a convex shape, aligning with optical profilometry measurements reported in the literature. The lab-based XRDI has the potential to be developed to map the wafer’s warpage in a shorter time and in situ, as can be perfectly performed in Synchrotron radiation source.

Investigation on Deterioration of Allura Red Dye Under Visible Radiation by TiO2 Based Nanocomposite

This current study is to prepare and characterise a Cu-doped Titanium dioxide (TiO2) and Cu-doped Titanium dioxide with Tungsten (WO3) nanocomposite and its application for the deterioration of Allura Red (AR) Dye. After preparing the Cu- doped Titanium dioxide (TiO2) with WO3 and Cu-doped Titanium dioxide (TiO2) nanocomposites using wet chemical Sol-gel method over various soaking times, the XRD, BET, and Ultraviolet-visible spectroscopy were used to determine the properties of the synthesized Copper-doped Titanium dioxide and Copper-doped Titanium dioxide with Tungsten nanocomposites. When Tungsten was added to Cu-doped Titanium dioxide (TiO2), the X-Ray Diffraction showed that all of the composites' peaks shifted slightly in the direction of a higher diffraction angle. To evaluate surface area BET curve was used. The Copper-doped Titanium dioxide (TiO2)/Tungsten (WO3) nanocomposite gives a significant photocatalytic activity because of its increased surface area. High surface area (BET) and anatase phase development (XRD), which are the main contributors to effective photocatalytic activity, were identified by the work's results. XRD revealed that the synthesised materials were in the anatase phase. Compared to CDT, CTW-15, CTW-30, and CTW-60 nanocomposites, the surface area (BET) of the CTW-45 nanocomposite is larger at 128.79 m2/g. By examining the kinetics of reaction parameters such as dopant concentrations, pH, catalyst dose, and dye concentration, the catalysts were able to determine the ideal conditions for improved photocatalytic degradation of Allura Red dye. At pH 4, dye concentrations of 5 mg/L, and CTW-45 concentrations of 100 mg/L, the percentage of AR dye degradation was greater. The findings of this study can be used to develop efficient nanocomposites that remove Allura Red dye from wastewater.

Real-Time Plasmonic Strain Sensors Based on Surface Relief Diffraction Gratings.

Large-scale diffraction gratings were fabricated in surface relief on azobenzene thin films and transferred to flexible PDMS substrates using soft lift-off lithography. The PDMS gratings were strained along the grating vector axis and the resulting surface topography was analyzed using diffraction angle measurements, AFM imagery and surface plasmon resonance (SPR) spectra. All measurement methods exhibited a linear response in strain indicating the useability of these sensors in real-world applications. For SPR-based strain sensing, an increasing pitch and a decreasing modulation depth were observed with increasing strain. The SPR peak shifted by ~1.0 nm wavelength and the SPR intensity decreased by ~0.3 a.u. per percentage of applied strain. The tested PDMS samples retained their integrity even after multiple cycles of stretching and relaxation, making them a suitable strain sensor.

Effects of Low-Temperature Heat Treatment on Mechanical and Thermophysical Properties of Cu-10Sn Alloys Fabricated by Laser Powder Bed Fusion.

This study investigated the impact of low-temperature heat treatments on the mechanical and thermophysical properties of Cu-10Sn alloys fabricated by a laser powder bed fusion (LPBF) additive manufacturing (AM) process. The microstructure, phase structure, and mechanical and thermal properties of the LPBF Cu-10Sn samples were comparatively investigated under both the as-fabricated (AF) condition and after low-temperature heat treatments at 140, 180, 220, 260, and 300 °C. The results showed that the low-temperature heat treatments did not significantly affect the phase and grain structures of the Cu-10Sn alloys. Both pre- and post-treatment samples displayed consistent grain sizes, with no obvious X-ray diffraction angle shift for the α phase, indicating that atom diffusion of the Sn element is beyond the detection resolution of X-ray diffractometers (XRD). However, the 180 °C heat-treated sample exhibited the highest hardness, while the AF samples had the lowest hardness, which was most likely due to the generation of precipitates according to thermodynamics modeling. Heat-treated samples also displayed higher thermal diffusivity values than their AF counterpart. The AF sample had the longest lifetime of ~0.19 nanoseconds (ns) in the positron annihilation lifetime spectroscopy (PALS) test, indicating the presence of the most atomic-level defects.

Angular dispersion and diffraction imaging analysis in a light wave oblique incident two-dimensional crossed grating

Based on the vector diffraction theory, the angular dispersion and diffraction imaging are analyzed in parallel light oblique incident two-dimensional crossed gratings. The results show that the angular dispersion presents a kind of increase-decrease-increase oscillatory change, and the maximum value of diffractive polar angle dispersion and total dispersion present an abrupt point. The angular dispersion is limited by the light wave incidence angle and two-dimensional gratings crossed angle. In addition, some obvious pincushion distortion has been formed in some cases. The angular dispersion increases with the increase of grating crossed angle in the permissible range, leading to enhancement of the diffraction imaging distortion. The results imply that there is an inherent relationship between the angular dispersion and the diffraction imaging in parallel light oblique incident crossed gratings.

Monitoring ocular disease via optical nanostructures potentially applicable to corneal contact lens products

Ocular diseases can cause vision problems or even blindness if they are not detected early. Some ocular diseases generate irregular physical changes in the eye; therefore, reliable diagnostic technology for continuous monitoring of the eye is an unmet clinical need. In this study, a pulsed laser (Nd:YAG) was used to create optical nanostructures on a hydrogel-based commercial contact lens. Simulations were used to determine the spacing of the nanostructures, which were then produced and tested on the lens in ambient humidity and fully hydrated environments. The nanostructures produced a 4° diffraction angle difference in response to the environmental changes. Vision obstruction was considered while designing the nanostructure features on the lens. The curved nanostructures exhibited a series of visible rainbow colors with an average range of 8° under normal room light. A spherical surface was also used to simulate the human eye, and application of a force (curvature change) caused the nanostructure spacing to change, influencing the visible color of the contact lenses. A smartphone camera application was used to measure the progress of ocular diseases by analyzing the RGB color values of the visible color. The nanostructures were also responsive to K+ ion variations in artificial tear fluids, with a 12 mmol L−1 sensitivity, which may allow the detection of ocular ionic strength changes.

15‐3: Reflective Liquid Crystal Polarization Volume Grating for SWIR with High Diffraction Efficiency and Large Diffraction Angle and Sensor Application

We have developed a reflective polarization volume grating using liquid crystal polymer for SWIR with high efficiency and a large diffraction angle. By using this grating and a lightguide system, we demonstrated a sensor system that can capture identical images simultaneously in both visible and SWIR light.

15‐1: Invited Paper: Intuitive Understanding of the Limitation of Pancharatnam‐Berry Optical Beam Deflectors

An approximate beam propagation method is proposed as an intuitive simulation of the optics of the Pancharatnam–Berry phase (PPD). Using this method, the limitation of PPD in diffraction efficiency for large diffraction angle is made clear.

Neutron Diffraction Measurements of Residual Stresses for Ferritic Steel Specimens over 80 mm Thick

The maximum thickness for ferritic steel specimens’ residual stress measurements using neutron diffraction is known to be about 80 mm. This paper proposes a new neutron diffraction configuration of residual stress measurements for cases that are over 80 mm thick. The configuration utilizes a neutron beam with a wavelength of 1.55 Å diffracted from the (220) plane with a diffraction angle (2θ) of 99.4°. The reason for the deep penetration capability is attributed to the chosen wavelength having enough intensities due to the low cross-section near the Bragg edge and the reduced beam path length (~16 mm) reflected by the large diffraction angle. Neutron diffraction experiments with this configuration can decrease strain errors up to ±150 με, corresponding to a stress of about ±30 MPa.

Holographic multiplexing in a photopolymerisable hybrid sol-gel

Holographic multiplexing techniques enhance functionality and information storage by leveraging the inherent selectivity of holograms. This is crucial for advancing holographic sensors, which excel in simultaneously detecting multiple parameters from a single input signal. This study explores the potential of the recent photopolymerisable hybrid sol-gel (PHSG) material for application in Space sensing systems through the investigation of its holographic angular multiplexing capabilities. For the first time, to the best of our knowledge, we report the successful recording of up to five angularly multiplexed gratings with diffraction efficiencies (DE) ≥ 15% in 187 ± 18 µm PHSG layers. A 3 mW/cm2 laser beam was used to record gratings (0–20° angular separation) with a spatial frequency of 800 ± 20 lines/mm utilising different exposure times. The study revealed that each successive multiplexing in the single-layer region resulted in a decrease in the material's recording sensitivity. Holographic recording sensitivity and DE growth during the grating formation period depend on the number of gratings multiplexed in the layer. The seven-month-old, multiplexed gratings demonstrate consistent DE, stable angular selectivity and diffraction angle. This study positions the PHSG material as a promising candidate for developing reliable multiplexed devices.

Synthesis and in-depth structure determination of a novel metastable high-pressure CrTe3 phase

This study reports the synthesis and crystal structure determination of a novel CrTe3 phase using various experimental and theoretical methods. The average stoichiometry and local phase separation of this quenched high-pressure phase were characterized by ex situ synchrotron powder X-ray diffraction and total scattering. Several structural models were obtained using simulated annealing, but all suffered from an imperfect Rietveld refinement, especially at higher diffraction angles. Finally, a novel stoichiometrically correct crystal structure model was proposed on the basis of electron diffraction data and refined against powder diffraction data using the Rietveld method. Scanning electron microscopy–energy-dispersive X-ray spectrometry (EDX) measurements verified the targeted 1:3 (Cr:Te) average stoichiometry for the starting compound and for the quenched high-pressure phase within experimental errors. Scanning transmission electron microscopy (STEM)–EDX was used to examine minute variations of the Cr-to-Te ratio at the nanoscale. Precession electron diffraction (PED) experiments were applied for the nanoscale structure analysis of the quenched high-pressure phase. The proposed monoclinic model from PED experiments provided an improved fit to the X-ray patterns, especially after introducing atomic anisotropic displacement parameters and partial occupancy of Cr atoms. Atomic resolution STEM and simulations were conducted to identify variations in the Cr-atom site-occupancy factor. No significant variations were observed experimentally for several zone axes. The magnetic properties of the novel CrTe3 phase were investigated through temperature- and field-dependent magnetization measurements. In order to understand these properties, auxiliary theoretical investigations have been performed by first-principles electronic structure calculations and Monte Carlo simulations. The obtained results allow the observed magnetization behavior to be interpreted as the consequence of competition between the applied magnetic field and the Cr–Cr exchange interactions, leading to a decrease of the magnetization towards T = 0 K typical for antiferromagnetic systems, as well as a field-induced enhanced magnetization around the critical temperature due to the high magnetic susceptibility in this region.

A comparative approach for estimating microstructural characteristics of BaTi1−xZrxO3 (0.0 ≤ x ≤ 0.3) nanoparticles via X-ray diffraction patterns

Barium titanate materials are currently a special topic for scientific research due to their effective technological applications. The tetragonal BaTi1-xZrxO3 (0.0 ≤ x ≤ 0.3) nanoparticles (NPs) were synthesized using a modified citrate technique. The current work provides a comparative approach for the calculation of crystallite size, stress, strain, and elastic characteristics based on X-ray diffraction (XRD) patterns. Various models have been developed to analyze XRD data; these models differ in their assumptions, mathematical approaches, and the type of information they provide. The Scherrer model ignores lattice micro-structures that develop in nanostructures, such as intrinsic strain. To overcome such drawbacks, three Williamson-Hall models, (the uniform deformation model (UDM)), the uniform stress deformation model (USDM), and the uniform deformation energy density model (UDEDM) have been discussed. According to the USDM model, with increasing Zr ion concentrations, interplanar space increases, causing a drop in Young’s modulus. All the previous approaches take into account the diffraction angle (2θ)-dependent peak broadening, which is thought to represent a combination of size and strain-driven induced broadening.Graphical

Exploring crucial technological advancements in Anger-Camera neutron detectors for single crystal neutron diffraction

In accordance with the second phase construction blueprint for the China Spallation Neutron Source (CSNS-II), the proposal includes the establishment of a single crystal neutron diffractometer. This apparatus necessitates a neutron detector array spanning over 1 m2 and capable of covering neutron diffraction angles from 20° to 160°. Additionally, the detector's position resolution must better than 1 mm × 1 mm. To meet such requirements, a scintillator neutron detector based on the Anger-Camera principle was designed. The detector is composed of a 6LiF/ZnS (Ag) scintillation screen, optical guide, silicon photomultipliers (SiPMs) array and self-design composite compression readout electronic systems. A detector prototype, featuring a detection area of 50 mm × 50 mm, was fabricated and subjected to testing at the BL20 neutron test line in the China Spallation Neutron Source (CSNS). The detector system achieved an optimal position resolution of 0.6 mm, while the maximum count rate was approximately 20 kHz. Moreover, the detector's Bragg edge imaging capability was preliminarily investigated using stainless steel samples, demonstrating its future potential for Bragg edge transmission imaging. The proposed detector demonstrates promising potential as a candidate for the single crystal diffractometer in CSNS-II.

Effects of ultrasonic power on the electrochemical characteristics of high-performance nanosized zinc–cobalt oxide electrodes for asymmetric supercapacitors

This study reports the preparation of ZnCo2O4 oxide (ZCO) electrode materials with favorable microstructure and porosity arrangement via ultrasonic electrodeposition-calcination. The application of ultrasonic waves at a power of 200 W (using ZCO-2) led to the development of a smooth and flat microstructure, characterized by the presence of numerous micropores. The lattice constant of ZnCo2O4 in the ZCO-2 oxide electrode material was determined to be 0.428 nm via TEM analysis. Furthermore, the XRD analysis of ZCOs demonstrated the effective synthesis of ZnCo2O4 electrode materials. The main lattice diffraction planes of ZCOs were observed at (111), (220), (311), (400), (511), and (440), with corresponding diffraction angles of 29.8°, 36.4°, 42.9°, 45.2°, 62.3°, and 66.5°, respectively. The application of 200 W ultrasonic power during electrochemical experiments significantly improved the electrochemical performance of ZCO-2. The ZCO-2 oxide electrode demonstrated remarkable area capacitance and negligible electrical impedance. At a current density of 3 mA/cm2, the area capacitance was measured to be 1.803 F/cm2. The ZCO-2 oxide electrode showed remarkable capacitance retention of 67.3 % even under high current density conditions. Furthermore, the asymmetric supercapacitor composed of ZCO-2 and AC (ZCO-2/AC ASC) showed outstanding electrochemical performance. The ZCO-2/AC ASC showed a capacitance of 5.721 F/cm3 at a current density of 0.5 mA/cm2. Furthermore, it demonstrated an energy density of 68.2 Wh/kg at a power density of 250 W/kg. The capacitor showed consistent performance and retained 63.8 % of its initial capacitance even after undergoing 24,000 cycles. Furthermore, the findings of this research provide substantial implications for the combination of ultrasonic electrodeposition with capacitors, while also presenting an innovative concept for electrode materials in high-performance supercapacitors.