Bulletin of Materials Science最新文献

The indium-free transparent conductive SnO₂:Mo/Ag/SnO₂:Mo tri-layer films were prepared by magnetron sputtering at room temperature for the first time, and the mechanism of the effect of Ag layer thickness on the properties of tri-layer films was systematically investigated. The results showed that the change of the morphology of Ag layer caused by the Ag layer thickness is the main factor for determining the optical and electrical properties of the SnO₂:Mo/Ag/SnO₂:Mo film. Moreover, the optical properties of the tri-layer film can be significantly optimized by adjusting the SnO₂:Mo layer thickness. The tri-layer films with the Ag layer thickness of 7 nm and SnO₂:Mo layer thickness of 40 nm exhibited optimum properties, with a maximum figure of merit of 2.5 × 10⁻² Ω⁻¹, a high visible light transparency of 84% and a low sheet resistance of 7 Ω/sq, and excellent mechanical flexibility. In addition, the application potential of the SnO₂:Mo/Ag/SnO₂:Mo electrodes were also demonstrated in the thin film transistor device.

Aluminium-bronze alloys are widely used in engineering applications due to their strength, wear resistance and corrosion behaviour. This study investigates the production of Cu-10 wt% Al alloys using the electric current-assisted sintering (ECAS) method, with sintering times of 10, 15 and 20 min, under a current range of 850 ± 50 A. The structural properties, phase composition, hardness, wear resistance and corrosion behaviour of the alloys were thoroughly examined. Scanning electron microscopy and energy-dispersive spectroscopy analyses revealed that the reactions continued with increasing sintering time. The hardness of the alloys increased with sintering duration, with values of 138 HV_0.1, 145 HV_0.1 and 176 HV_0.1 for the 10, 15 and 20-min sintering times, respectively. After 20 min of sintering, the hardness of the alloy was 2.5 times higher than that of pure Cu and pure Al. The Cu-10 wt% Al alloy sintered for 20 min exhibited superior friction and wear properties, suggesting that prolonged sintering led to the formation of intermetallic phases. Additionally, the corrosion resistance improved with longer sintering times, with the sample sintered for 20 min showing the best protective surface characteristics, attributed to the formation of intermetallic compounds, such as CuAl₂. All findings were supported by regression analysis and surface response graphics. These results demonstrate that optimized ECAS parameters can significantly enhance the mechanical and corrosion properties of Cu-Al alloys.

This study investigates the impact of Ti substitution on the microstructural features, mechanical hardness, martensitic transformation behaviour and magnetic hyperfine interactions of FeNiSi-based alloys. FeNiSi and FeNiSiTi alloys were synthesized via arc melting and subsequently characterized using scanning electron microscopy, Vickers microhardness testing, differential scanning calorimetry (DSC) and Mössbauer spectroscopy. Microstructural analysis revealed that the Fe-34.5%Ni-4.2%Si alloy exhibits an austenitic matrix with lenticular martensitic structures, while Fe-28.5%Ni-4.1%Si-0.6%Ti alloy showed microstructural changes attributed to lower nickel content and titanium addition. Mechanical hardness measurements showed that the Fe-28.5%Ni-4.1%Si-0.6%Ti alloy exhibited lower microhardness compared to the Fe-34.5%Ni-4.2%Si alloy, which is potentially due to reduced nickel content, coarser grain size or processing variations. DSC analysis indicated nearly identical martensitic transformation temperatures for both alloys, but the Fe-28.5%Ni-4.1%Si-0.6%Ti alloy exhibited a significantly more distinct exothermic peak, releasing approximately 65 times more energy during transformation, suggesting a more extensive or complete phase transformation in the titanium-containing alloy. Mössbauer spectroscopy confirmed the presence of both magnetic (martensite) and non-magnetic (austenite) phases in both alloys. The Ti-containing alloy showed a slight increase in the volumetric percentage of the austenite phase and a weakening of magnetic interactions within the ferromagnetic phases, along with changes in isomer shift and quadrupole splitting values. This indicates the influence of titanium on the electronic environment and local symmetry around iron nuclei. These results highlight the significant role of titanium in influencing the microstructural evolution, mechanical properties and phase transformation characteristics of FeNiSi-based alloys.

Under the virtual crystal approximation (VCA), the pseudopotential approach (EPM) has been applied to our calculations. The lattice vibrational, electronic, and optical properties of GaAs_1-xP_x alloy for fixed values of temperature are calculated and their dependence on the GaP concentration is examined. The used technique represents the first theoretical predictions for compositions x in the range 0–1, whereas our results for GaAs (x=0) and GaP (x=1) are generally in reasonable accord with the known data in the literature. Our findings showed the transition from direct to indirect energy band gap at various temperatures for the GaAs_1-xP_x alloy and the results may help us understand the heat dissipation in computer chips and thermoelectric devices.

Double perovskite materials present significant advantages in terms of stability, environmental safety, tunability, charge dynamics and efficiency, making them a promising avenue for future solar cell technologies. In the present study, the numerical simulation for the photovoltaic performance of lead-free halide double perovskites (HDPs) X₂AgBiI₆ (where X = Rb, K) estimated using the one-dimensional solar cell capacitance simulator (SCAPS-1D) package is discussed in detail. A range of electron transport layers (ETLs) such as zinc oxide (ZnO), titanium oxide (TiO₂), fullerene (C₆₀), indium gallium zinc oxide (IGZO), tin oxide (SnO₂) and [6,6]-phenyl-C₆₁-butyric-acid methyl ester was varied to identify the best fit. Similarly, the hole transport layers (HTLs), namely cuprous oxide (Cu₂O), cuprous thiocyanate (CuSCN), copper antimony sulphide (CuSbS₂), nickel oxide (NiO), poly(3-hexylthiophene), PEDOT: PSS (poly(3,4-ethylenedioxythiophene) polystyrene sulphonate), spiro-MeOTAD (2,2′,7,7′-tetrakis[N,N-di (4-methoxyphenyl)amino]-9,9′-spirobifluorene), CuI (copper iodide), CuO (cupric oxide), V₂O₅ (vanadium pentoxide), CBTS (copper-barium-tin-sulphide) and CFTS (copper ferrous tin sulphide), respectively, were extensively studied in solar device configuration. The influence of various physical parameters, such as different layers, thickness of ETL and HTL and temperature, was investigated. The performance of the proposed HDPs improved with increases in layer thickness and decreases in temperature. The proposed studies may pave the way towards more stable and efficient HDPs for futuristic photovoltaics.

The investigation on obtaining composite material based on Ni–Ti–Al system has been carried out in this article. Experimental samples were obtained using two methods: pressing and additive forming. Samples of nickel, titanium and aluminium powders were pressed under a pressure of 4 tons in order to study the physical and mechanical properties of the obtained materials. The concentrations of titanium and aluminium varied from 10 to 20 wt%. The physical and mechanical characteristics of the experimental samples were studied; in particular, the density, Rockwell hardness, Vickers microhardness and flexural strength. It was shown that at a concentration of 20% titanium and aluminium, high values of physical and mechanical properties were obtained, with the bending strength of 810 MPa. In this study, a screw extruder was developed, which enabled the production of 3D-printed products with a small proportion of polymer binder. Using the FDM (fused deposition modelling) method, experimental samples were obtained from a mixture of Ni 80% + (Al + Ti) 20% and its properties were determined. The phase composition of the obtained samples was studied, revealing that the main phases formed during sintering are intermetallic compounds, specifically Ni₃Al and Ni₃ (Al, Ti).

Producing multi-layer soundproofing materials by combining materials with different properties is a widely used method. The production of these types of structures utilizes the superior properties of each layer contained within the structure. This study addresses the acoustic performance of nonwoven surface structures fabricated in different thicknesses and densities using chicken feather fibres in different constructions. An impedance tube was used to determine the sound absorption and sound transmission loss values of two-layer structures of different densities and thicknesses. The results show that the influence of the layer in front or behind on the values of sound transmission losses is very limited in two-layer structures with varying densities and thicknesses. However, for the degree of sound absorption, it is important which layer is closer to the sound source. These findings are based on an analysis of multifactorial experimental data. Accordingly, the sound absorption coefficients and sound transmission loss values of all two-layer structures decrease slightly with increasing sound frequency in the frequency range of 63–200 Hz and then increase. The low-density layer on the front of the combined structure ensures better sound absorption at low and medium frequencies. As the density of the front layer increases, its ability to absorb sound decreases. It has been found that the sound absorption capacity of structures with a low density on the front and a thick layer on the back is highest.

This study investigates the effects of doping MgH₂ with rhodium (Rh) on hydrogen desorption activation energy, utilizing kinetic Monte Carlo simulations to elucidate the underlying mechanisms. The introduction of this transition metal significantly influences the desorption kinetics, with activation energies measured at 128.2 kJ mol^–1 for 6.25 wt% Rh and 136.3 kJ mol^–1 for 3.125 wt% Rh. The kinetic Monte Carlo simulations provide detailed isothermal Temperature Programmed Desorption profiles for each doped system, revealing that 6.25 wt% Rh doping notably reduces the activation energy and time required for hydrogen desorbed, thereby enhancing the desorption process. Rh doping presents intermediate effects, offering a nuanced understanding of how transition metal doping can be tailored to optimize hydrogen storage in MgH₂. These findings contribute valuable insights into the design of advanced hydrogen storage materials, making this study a significant addition to the field.

CuCr₂O₄ and Fe-substituted CuCr₂O₄ nanoparticles were synthesized via the sol–gel method, and their structural, morphological and optical/electrical properties were investigated using X-ray diffraction (XRD) and terahertz spectroscopy. XRD analysis revealed that the parent compound exhibits a tetragonal spinel phase, while Fe substitution induces a phase transition towards the cubic spinel structure. Dynamic light scattering measurements indicated a decrease in average particle size with increasing Fe content. Additionally, zeta potential measurements showed a reduction in surface charge upon Fe substitution, suggesting changes in colloidal stability or surface chemistry. Terahertz spectroscopy revealed that increasing Fe content led to a progressive increase in absorption coefficient, refractive index and dielectric constant across the series. As a result, the electrical conductivity of the nanoparticles increased with Fe substitution, likely due to enhanced charge carrier mobility or polaron hopping facilitated by the Fe dopants.

Two new hybrid compounds were synthesized by combining potassium N–(4-methylphenylsulfonyl)dithiocarbimate (DCBI) with layered zinc hydroxy salts: zinc hydroxynitrate (ZHN) and zinc hydroxyacetate (ZHA), using a coprecipitation method. The materials were characterized by X-ray diffraction (XRD), infrared spectroscopy (FTIR), scanning electron microscopy (SEM) and thermogravimetric analysis (TGA), confirming the incorporation of the organic anion into the layered structure. DCBI and the host layers interact mainly through the CS₂ group. The compounds were evaluated as accelerators in the vulcanization of rubber and compared to the commercial accelerator ZEDC. The synthesized materials led to slower vulcanization reactions and vulcanizates with higher elongation at break and lower tear resistance. These features suggest that the materials may be suitable for applications that require greater flexibility and improved safety, presenting a promising alternative to conventional amine-based accelerators.

Graphical abstract

The vulcanization process was conducted with the interlayer materials synthesized in this work.