A near-infrared (NIR) reflector in cotton clothes may prevents several dermatological problems. TiO₂ is commonly used for the NIR reflector coating in cotton. The NIR reflectance value is expected to increase if smaller TiO₂ particles were used. A simple mechanical process of ultrasonic wet-milling to reduce the TiO₂ particle size is proposed in this study. The reduction process utilizes ultrasonic cavitation by an ultrasonic homogenizer has succeeded in reducing the particle size from 170 to 80 nm as indicated by particle size measurement results and as supported by transmission electron microscopy results. The wet-milling particles of 80 nm TiO₂, along with 170 and 280 nm TiO₂, were used to coat cotton fabrics. Optimization of the coating process was performed using citric acid and chitosan as binder agents. The effect of citric acid and chitosan was studied through NIR spectroscopy, scanning electron microscopy, and X-ray fluorescence. From the NIR spectroscopy characterization results, it is found that the fabrics which are coated with the smallest TiO₂ particle size (80 nm) indeed show highest NIR reflectance among others.

The influence of the channel shape in a junctionless silicon- on-insulator finned field-effect transistor (JL SOI FinFET) on the amplitude of random telegraph noise (RTN) induced by single interface trapped charge has been simulated for the transistors with rectangular, trapezoidal, and triangular fin cross sections. The simulation of the RTN amplitude distribution along the channel induced by a single charge trapped at interface defect located at the fin top and at sidewall of JL SOI FinFETs with channels of different shapes is considered. It is established that at trapping the single charge at sidewall surface of the channel, the lowest RTN amplitude is seen for the triangular cross-section and the highest for the rectangular and trapezoidal cross-sections. At the single charge trapping at the top surface of the channel, the RTN amplitude is higher for the rectangle than for the trapezoidal cross-section.

Spatially arranged surfaces on the micro-rod structure, which was three-dimensionally (3D) architected on a Si(110) substrate have been thoroughly investigated by a system with micro-beam reflection high-energy electron diffraction (μ-RHEED) and scanning electron microscopy (SEM). The combination of μ-RHEED and SEM realized analytical structure investigation of 3D surfaces with the spatial resolution of sub micrometer for the 3D rectangular shaped rod consisting of a (110) top surface (20 μm wide) and {111} vertical side surfaces (10 μm wide). Exhaustive mapping revealed the peculiar reconstructed surface structures: Si(110) “16 × 2” single domain and {35 47 7} facet surfaces locally appeared on the interconnected edge region on the 3D structure in addition to the “16 × 2” and 7 × 7 super structures on flat top (110) and side {111} surfaces, respectively. The formation mechanism for “16 × 2” single-domain structure near the corner edge of the (110) surfaces and {35 47 7} facets on the corner edges between (110) and {111} surfaces were discussed from the viewpoint of the surface stability on the 3D geometrical shaped Si structure.

Temporal variations of valence states of the α-YbAl_1−xFe_xB₄ crystals (x = 0, 0.013, and 0.098) are experimentally examined in a nanosecond time-scale by time-resolved photoemission experiments using synchrotron radiation. The Yb 4f spectral features show no apparent change with time during relaxations after the optical pumping. The present experimental result indicates that dynamics of valence fluctuations in the material are likely dominated by a picosecond or much faster time-scale. The time-resolved measurement at the time-resolution limit at synchrotron radiation captured the trace of valence fluctuations.

Bismuth oxide/indium oxide microspheres have been synthesized by a facile ethylenediaminetetraacetic acid (EDTA)-assisted hydrothermal process using sodium bismuthate and indium nitrate as raw materials. The obtained products were analyzed by X-ray diffraction (XRD), scanning electron microscopy (SEM), and solid ultraviolet-visible diffusion reflectance spectroscopy. XRD and SEM observations show that the obtained microspheres consist of tetragonal Bi₂O₃ and cubic In₂O₃ phases with a smooth surface and diameters between 150 nm and 1 μm. EDTA, hydrothermal temperature, and reaction time play essential roles in the formation of the bismuth oxide/indium oxide microspheres. The tetragonal Bi₂O₃ and cubic In₂O₃ phases are formed with increasing the hydrothermal temperature and the reaction time. Photocatalytic performance of the bismuth oxide/indium oxide microspheres was evaluated by photocatalytic degradation of rhodamine B in an aqueous solution with solar light irradiation. A rhodamine B degradation ratio depends on the solar light irradiation time and the microspheres dosage. Rhodamine B with 10 mg L⁻¹ can be entirely removed by more than 10 mg of the bismuth oxide/indium oxide microspheres in the 10 mL aqueous solution under solar light irradiation for 6 h.

Portland cement slurries have undergone degradation due to carbonation-induced corrosion in contact with a CO₂-rich environment. Many studies have observed degradation such as a decrease in the mechanical strength and an increase of permeability and porosity. When utilized in wells as a zonal isolation material in the CO₂-rich environment, such degradation can be worsen by hydration shrinkage of Portland cement, in which micro-annuli are formed and, thus, effective permeability is increased. In this work, CaO was employed as an expansive additive admixed with Portland cement. The samples were hydrated for 1 and 7 days prior to carbonation for 14 days in an autoclave to simulate shorter and longer hydration times before contacted with a CO₂-rich environment. Before carbonated in the autoclave, the samples were analyzed by X-ray diffraction. The expansion of the hydrated slurries was also observed for the first 24 h of hydration. After carbonation, the percentage of the corroded area was calculated, and a three-point bending test was conducted. The result shows that the CaO additive below 15% by weight of cement in the Portland cement slurry can enhance the slurry resistance against corrosion encroachment induced by the carbonation process. The presence of the CaO additive in the Portland cement slurry can mitigate the severe detrimental effect induced by carbonation.

This study presents the inhibitive property of Co(II) ions in the corrosion protection of commercial hot-dip galvanized steel in aggressive solution. The polarization measurements reveal the action of Co(II) cations in the anodic branch with the inhibitive efficiency determined at 96% for 0.01 M of Co(II). The corrosion resistance was reinforced by a passive layer formed at Zn surface, that was assessed by the electrochemical measurements. The existence and the crystal structure of this protective layer was analyzed by field-emission scanning electron microscopy observations. X-ray diffraction analysis was confirmed the formation of zinc cobalt hydroxide and cobalt zinc oxide on the Zn surface that attributed to the inhibitive action of the Co cations.

The microwave absorbers based on BiFeO₃ have been widely used in the microwave absorbing region due to their excellent electromagnetic characteristics and properties. This study investigated the Li doping effect on the structure, magnetic properties, and microwave absorption efficiency of Bi_1−xLi_xFeO₃ nanoparticles (x = 0.02, 0.04, and 0.06), which were created using the sol-gel method. The test results showed that the increase in the Li doping concentration affects the ferromagnetic properties of the material. The highest magnetic properties were obtained at a concentration of x = 0.06. The magnetic saturation value M_s = 5.4 emu g⁻¹, the magnetic remanence value M_r = 1.53 emu g⁻¹, and the coercive field H_c =106.73 Oe were obtained from the concentration x = 0.06. The doping of x = 0.06 produced three absorption peaks, and the highest absorption peak was −46 dB at 11.22 GHz. To identify the microstructures and electromagnetic properties of the preliminary samples, X-ray diffraction, scanning electron microscopy, and vector network analysis studies were performed. The results showed that Bi_1−xLi_xFeO₃ nanoparticles were successfully collected and that the prepared samples had excellent absorption properties. Overall, due to their outstanding microwave absorption efficiency, Bi_1−xLi_xFeO₃ nanoparticles have numerous potential applications.

We investigated the electrical and optical properties of ITO/Ag-alloy/ITO films in a corrosive NaCl solution. The effects of bending fatigue combined with aggressive environments provided by the salt solution were also studied. It is shown that exposure to the salt solution can cause the ITO/Ag-alloy/ITO performance to degrade over time. In addition, greater changes in electrical resistance and lower values of optical transmittance were observed at higher concentrations of the salt solution. The combination of stress and corrosion by the aqueous NaCl solution was found to significantly reduce the conductivity of the ITO/Ag-alloy/ITO film. Furthermore, it is shown that the presence of structural defects in the deposited films can provide a driving force to form Ag agglomerations that, in turn, degrade the conductivity of the ITO/Ag-alloy/ITO film. This suggests that defects in the film should be minimized to avoid excessive corrosion.

The energy loss function (ELF) describes the interaction between electrons and matter in solids. Electron inelastic mean free paths (IMFPs), which are important and basic parameters for describing electron inelastic scattering in matter, have been calculated theoretically from the ELFs of materials. These are essential for understanding quantitative surface spectroscopies, such as Auger electron and X-ray photoelectron spectroscopy. However, the optical constants or the ELFs of most compounds are unknown in the 10—50 eV energy range, where electron-solid interactions are strong, owing to experimental difficulty. In this study, the ELFs and the optical constants were calculated for 35 inorganic semiconductors [AgBr, AgCl, AgI, AlAs, AlN, AlSb, cubic-BN (c-BN), hexagonal-BN (h-BN), CdS, c-CdSe, h-CdSe, CdTe, C (diamond), GaAs, GaN, GaP, GaSb, GaSe, Ge, InAs, InP, InSb, PbS, PbSe, PbTe, Se, Si, c-SiC, h-SiC, SnTe, Te, c-ZnS, h-ZnS, ZnSe, and ZnTe] in a wide energy range (from 0.1 eV to 1 MeV) using first-principles calculations with FEFF and WIEN2k. The resulting 35 ELFs were evaluated using two sum rules, the f-sum rule and the Kramers-Kronig sum rule, resulting in average relative errors of 1.6% and 0.05%, respectively. The calculated ELFs for InAs, GaAs and InSb agreed well with the experimental ELFs obtained from the transmission electron energy loss spectroscopy (EELS) experiments and the reflection EELS experiments. The resulting database of the ELFs and the optical constants for 35 compound semiconductors was concluded to be accurate and useful for understanding the inelastic scattering processes of semiconductors with respect to IMFPs and electron stopping powers. All detailed data are available in the materials data repository provided by the National Institute for Materials Science (https://doi.org/10.34968/nims.1434).

Metal nanoshells and nanotubes with dielectric cores are useful structures to change the surface plasmon frequencies in the wide range. Here, our localized plasmon theory derived in the random phase approximation at high frequency condition is applied to investigate the localized plasmon excitations for metal nanoshells and nanotubes with dielectric cores, which are embedded in dielectrics. Assuming that local dielectric functions for metals and dielectrics have step function shapes at the metal and dielectric interfaces in the quasi-static approximation, analytical formulas can be derived for the localized plasmon excitation. It is found that the bonding and antibonding localized surface plasmons are excited when the nanoshell and nanotube have finite thicknesses and that the surface plasmon frequencies can be controlled in the wide range by changing the ratio of the inner radius to the outer one of the nanoshell and nanotube. The localized surface plasmons, however, are not excited in the zero-thickness limit, i.e., two-dimensional shell where only the lights are emitted from the interfaces of dielectric cores and surrounding dielectrics.

Research of oxynitrides is a new trend in developing new functional material. Getting information about the local structure around the cation is crucial because the arrangement of the anions affects the cations and the displacement of cations can be related to their physical properties. To study the effects of mixed anions on the behavior of the cations in oxynitrides, we applied X-ray fluorescence holography on a CaTaO₂N thin film. Atomic images reconstructed from Ta Lα holograms clearly showed the atomic positions around Ta. By comparing the intensities of the Ta and Ca atomic images, we found that the fluctuations of the Ta atoms are larger than the Ca atoms.

Nanorod-shaped strontium tin hydroxide in a hexagonal SrSn(OH)₆ phase with a diameter and a length of 100 nm and several micrometers, respectively, has been synthesized via a one-step hydrothermal route using sodium stannate and strontium nitrate as raw materials. The influence of a reaction temperature and a reaction time on morphology and the size of the products has been investigated. The structure, micro-morphology, the size, and optical absorption of nanorod-shaped strontium tin hydroxide were investigated by X-ray diffraction, electron microscopy, and solid ultraviolet-visible diffuse reflectance spectroscopy. Photocatalytic activity of nanorod-shaped strontium tin hydroxide has been evaluated by photodegradation of crystal violet under ultraviolet irradiation. Nanorod-shaped strontium tin hydroxide shows good photocatalytic performance with complete degradation of crystal violet after 6 h. The relationship among the photocatalytic activity, the irradiation time, and a content of nanorod-shaped strontium tin hydroxide is analyzed. The stability and a possible photocatalytic mechanism for degradation of crystal violet using nanorod-shaped strontium tin hydroxide are discussed. Nanorod-shaped strontium tin hydroxide is an efficient photocatalyst for degradation of crystal violet.

First-principles total-energy calculations were applied to 0 to 1 ML of silicon-embedded Ni(100) surfaces in the outmost layer within a 2 × 4 unit cell. Up to a half monolayer of embedded silicon, the surface energy decreased monotonically with increasing the number of embedded silicon, and the lowest energy structure was a √2 × √2-R45° [or c(2 × 2)] structure with diagonally aligned embedded silicon of 0.5 ML. Beyond the half monolayer, the surface energy increased with increasing the number of embedded silicon. The energy of the silicon-embedded structure in the outmost layer of the Ni(100) surface was compared with silicon embedded in the second layer and silicon adsorbed on the Ni(100) surface. Both configurations gave higher energies, which shows the robustness of the √2 × √2-R45° structure on the Ni(100) surface. The present results are in perfect agreement with our recent report [T. Fukuda et al., Jpn. J. Appl. Phys. 59, 065501 (2020)].

Transition metal dichalcogenides possess properties such as low cost, easy fabrication, and suitability for various applications. Monolayer WTe₂ is a potential electro-catalytic material for the oxygen reduction reaction (ORR). However, the reaction mechanism on pure and S-doped monolayer WTe₂ remains unknown; therefore, this work is devoted to clarifying the current topic using density functional theory calculations and a thermodynamics model. We found that the ORR mechanism is a four-electron pathway on pure and S-doped monolayer WTe₂. However, S-doped monolayer WTe₂ increases the thermodynamic barrier of the ORR compared to pure monolayer WTe₂. Therefore, the S dopant decreases the performance of WTe₂. The result implies that doping with different elements is not always a method to improve the efficiency of chemical reactions.

The thermoelectric response of bilayer graphene over a wide temperature range (0 < T ≤ 400 K) was theoretically investigated using linear response theory combined with a Green's function technique. We found that the power factor PF for a fixed chemical potential μ exhibits a maximum at a certain T. On the other hand, we found that the PF for a fixed T exhibits a maximum (PF_max) at an optimal μ [or optimal carrier concentration (n_opt)]. In addition, we clarified the T dependence of n_opt and PF_max and explained the existence of n_opt in terms of the thermal excitation of electrons between the valence and conduction bands, which cannot be predicted by the conventional Mott formula.

The surface diffusion method was used to produce tungsten (W) nanopyramids coated with monolayer films of platinum (Pt) and gold (Au). Although the general structures of the nanopyramids were the same, the top of the nanopyramids was different from the Pt and Au cases, i.e., a monomer was observed for Pt, whereas a trimer observed for Au. The effects of simultaneous heating and the electric field on the structural evolution of nanopyramids were also studied. We observed that the broken nanopyramids were rapidly regenerated by heating in an electric field. The opening angles of field-emitted electrons were found to be approximately ±2° and ±2.5° for Pt and Au, respectively. From the obtained results, it was observed that the field-emission properties of all specimens were almost the same.

The contrast of a photoelectron microscopy image depends on the type of excitation photon source and the photoelectron kinetic energy. The contrast inversion observed in the photoelectron image by Hg lamp excitation is due to differences in work functions specific to materials and surface conditions, and the contrast inversion in the case of vacuum ultraviolet light excitation is due to the difference in the valence band density of states. The mechanism of contrast formation in valence photoelectron images is well understood qualitatively as described above, but quantitative evaluations are required for accurate understanding. We investigated the photoelectron image contrast of gold checkerboard pattern printed on the silicon wafer. The intensity of the gold region near the Fermi level is higher than that of the silicon substrate region, while the inverted contrast images were obtained at lower kinetic energies. We found that in the case of core and valence photoelectrons, certain contamination degrades the image quality, but in the case of Hg lamp excitation, it increases signal intensity owing to the lowering of work function.

The Debye-Waller factor's unit and notation [σ² (10⁻⁴ Ų)] in Table 1 on p. 26 in the original article were incorrect. The correct Debye-Waller factor in Table 1 is shown in this erratum. This correction does not affect the results and the conclusion of the original article.