Structural Properties Research Articles

Tailoring Structural and Magnetic Properties: Cd²⁺ and Cu²⁺ Co-Doped Ni-Zn Ferrite Nanoparticles via Sol-Gel Auto-Combustion

In this research work, we have incorporated paramagnetic Cu2+ and diamagnetic Cd2+ cations in spinel ferrites. By adjusting the concentrations of Cu and Cd, it is possible to achieve a balance between enhanced electrical conductivity, desired magnetic properties, and suitable structural characteristics for applications in high-frequency devices, magnetic sensors, and electromagnetic interference (EMI) suppression through a synergistic effect. The sol-gel auto-combustion method was employed to synthesize Cd²⁺ and Cu²⁺ co-doped Ni₀.₅Zn₀.₅₋ₓ₋ᵧCuₓCdᵧFe₂O₄ (x = y = 0.0, 0.05, 0.1, 0.15, 0.2) ferrite nanoparticles. Structural, morphological-compositional, functional, and magnetic properties of the nanoparticles were characterized using X-ray diffraction (XRD), field emission scanning electron microscopy with energy dispersive spectroscopy (FESEM-EDS), Fourier-transform infrared spectroscopy (FT-IR), and vibrating sample magnetometry (VSM). The XRD results confirmed the single-phase spinel structures with lattice constants increasing with higher dopant concentrations. The average crystallite sizes were found in the range of 38.14 - 42.68 nm and lattice constants in the range of 8.389 - 8.423 Å. Morphological analysis revealed agglomeration, consistent with the stoichiometric proportions during synthesis. There is a decreasing trend in nanograin sizes in the range of 40 to 73 nm with the concentration. FT-IR spectra verified the spinel structures through characteristic absorption bands around 600 cm⁻¹ and 400 cm⁻¹. Magnetic measurements indicated a decrease in saturation magnetization with increasing dopant levels indicating their potential use in electromagnetic wave absorption and magnetic memory devices.

A hierarchical Cu2SnO4@NiCo-LDH nanofilament structure as a new-potent electrode for energy storage

Our research continues to explore innovative, efficient electrode materials and new production processes for electrochemical devices. Supercapacitors remain at the forefront of energy storage solutions, thanks to their exceptional power density, cycling durability, and mechanical robustness. For the first time, we have developed a hierarchical Cu2SnO4@NiCo-LDH nanocomposite using a straightforward hydrothermal technique coupled with an annealing process on a nickel foam substrate. This study introduces the novel Cu2SnO4@NiCo-LDH (CSO@NC-LDH) material, distinguished by its unique nanofilament structure and impressive electrochemical properties, including a high specific capacitance of 2791.5 F g−1 at 1 A g−1. Additionally, we created an asymmetric supercapacitor using CSO@NC-LDH for the positive electrode and activated carbon (AC) for the negative electrode. This system showcases an outstanding energy density of 108.67 Wh kg−1 and a notable power density of 1.05 kW kg−1 at an operating voltage of 1.6 V. These exciting results highlight the promising potential of CSO@NC-LDH nanofilaments as advanced electrodes for next-generation energy storage devices.

First principles investigation for the hydrogen storage properties of novel lithium-based XLiH3 (X=K, Rb) perovskite-type hydrides for advance hydrogen storage system

In this work, the density functional theory is used to investigate the structural, mechanical, electronic, dynamic, thermodynamic, optical and hydrogen storage properties of XLiH3 (X=K, Rb) for the first time. Both KLiH3 and RbLiH3 materials exhibit dynamic, mechanical and thermodynamic stability. The lattice parameters of KLiH3 and RbLiH3 are 3.908 and 4.070 Å, respectively. The investigation of Cauchy pressure, Poisson's ratio and B/G ratio shows that KLiH3 and RbLiH3 are brittle materials. Moreover, the electronic properties of XLiH3 hydrides demonstrate that KLiH3 and RbLiH3 show metallic nature. Optical properties of these compounds are studied and reveal that they have very high refractive indexes and dielectric functions. The thermodynamic properties, including heat capacity, entropy, enthalpy, and free energy of XLiH3, are investigated as well. The hydrogen storage capacities of KLiH3 and RbLiH3 are 5.805 and 3.071 wt%, respectively, confirming that KLiH3 has a high hydrogen storage capacity and is more suitable as a hydrogen storage material. Our study opens up a new-pathway for designing novel hydrogen storage materials.

Sintering Driven Void Formation in PS@WO3 Core-Shell Composites: A Photodegradation Enhancement Strategy

Background: Polystyrene nanospheres are used as a substrate for the hydrothermal coating of tungsten trioxide (WO3) to form a core-shell composite of PS@WO3. The core-shell structure is used for the next sintering step. This produces porous WO3. The focus of this study is on the role of porous WO3 in enhancing photocatalytic performance. Methods: The hydrothermal method was employed for coating, and the surface morphology, as well as the structural properties of WO3-coated PS spheres, were systematically investigated using SEM and XRD analyses. Additionally, the sintering process was introduced to enhance the material by inducing rupture in the PS sphere core, creating voids that significantly increased the material's surface area. Results: The evaluation of the effect of sintering temperature on photodegradation efficiency highlighted the crucial role of sintering temperature. Un-sintered and 300°C sintered WO3, both having a hexagonal crystalline structure, exhibited superior degradation efficiencies compared to samples sintered at higher temperatures (400°C and 500°C). In particular, the 300°C sintered WO3 outperformed its un-sintered counterpart despite identical crystalline structures. The performance of the PS@WO3 composite was assessed to determine the enhanced role of porous WO3. The porous WO3 obtained, in particular by the sintering of the core-shell PS@WO3 composites at 300°C, showed a remarkable improvement in the degradation efficiency. These composite demonstrated over 95% efficiency within 10 minutes and achieved near complete (100%) degradation for a further 10 minutes, surpassing the performance of pure WO3. It is important to clarify that while the final product was predominantly WO3 after the sintering process, the inclusion of PS served a critical purpose in creating voids during sintering. The PS@WO3 composite structure used as a resource for the preparation of porous WO3, even with a potentially reduced PS composition, has been found to play a significant role in influencing the surface area of the material, and consequently the photocatalytic performance. Conclusion: The study has highlighted the importance of crystalline structure and sintering conditions in optimizing the efficiency of photocatalytic materials. The porous WO3 obtained, in particular by the sintering of the core-shell PS@WO3 composites at 300°C, showed promising potential for applications under UV and visible LED light irradiation. These results provide valuable insights for the development of advanced photocatalytic materials with improved performance, highlighting WO3 as the key contributor to the observed improvements.

The Dye-Contaminated Water Treatment Efficiency of Two Types of Geopolymers: A Comparative Study of Structural, Microstructural and Adsorption Properties

The Dye-Contaminated Water Treatment Efficiency of Two Types of Geopolymers: A Comparative Study of Structural, Microstructural and Adsorption Properties

A DFT Approach to Insight on the Structural, Optoelectronic and Thermoelectric Properties of Cubic Perovskites YXO3 (X = Ga, In) for Renewable Energy Applications

A DFT Approach to Insight on the Structural, Optoelectronic and Thermoelectric Properties of Cubic Perovskites YXO3 (X = Ga, In) for Renewable Energy Applications

Effects of Nd-ions doping on the phase structure and electrical properties of PSN-PMN-PT ceramics

Effects of Nd-ions doping on the phase structure and electrical properties of PSN-PMN-PT ceramics

Photo-Energized MoS2/CNT Cathode for High-Performance Li–CO2 Batteries in a Wide-Temperature Range

HighlightsThe unique layered structure and excellent photoelectric properties of MoS2 facilitate the abundant generation and rapid transfer of photo-excited carriers, which accelerate the CO2 reduction and Li2CO3 decomposition upon illumination.MoS2-based photo-energized Li–CO2 battery displays ultra-low charge voltage of 3.27 V, high energy efficiency of 90.2%, superior cycling stability after 120 cycles and high rate capability.The low-temperature Li–CO2 battery achieves an ultra-low charge voltage of 3.4 V at –30 °C with a round-trip efficiency of 86.6%.

Synthesis, Structure, and Optical Property of [6]Cyclo‐1,2‐naphthylene

A one‐pot procedure with cobalt‐mediated oxidation of 2,2’‐dilithio‐1,1’‐binaphthyl by ferrocenium salts afforded the chiral cyclic hexamer of naphthylene, [6]cyclo‐1,2‐naphthylene (1). The molecular structure of 1 was determined by single crystal X‐ray crystallography and NMR analyses, revealing its cyclic structure with an approximate D3 symmetry. Compound 1 exhibits blue emission at 383 nm with high photoluminescence quantum yield of 97%, which can be attributed to its rigid twelve‐membered ring structure. Optical resolution of 1 by chiral HPLC allowed for the evaluation of its chiroptical properties. Each enantiomer exhibits circular dichroism with complex Cotton effects, which are grouped into three positive or three negative couplets. Circularly polarized luminescence is observed at 383 nm with an anisotropy factor |glum| on the order of 10–4. The high photoluminescence quantum yield and the CPL properties of 1 indicate its potential application as a CPL emitter.

Linear and cylindrical friction stir additive manufacturing (FSAM) of AA6061-T6 by consumable rods: metallurgical structure, wear, and corrosion properties

Linear and cylindrical friction stir additive manufacturing (FSAM) of AA6061-T6 by consumable rods: metallurgical structure, wear, and corrosion properties

Statistical analysis of Cu content effects on structural properties in CuZr metallic glasses

This study examines the effects of casting conditions on the structural properties of CuZr metallic glasses (MGs) using molecular dynamics simulations. The influence of Cu content on various structural properties was explored, finding significant power-law relationships that indicate increased Cu promotes the formation of icosahedra-like structures and enhances the population of solid-like polyhedra. In contrast, the clustering coefficient, reflecting solid-like connectivity, showed a linear relationship with Cu content, revealing that while Cu increases solid-like structures, their connectivity does not scale proportionally. No significant correlations were found for sample volume, cooling rate, or temperature within the studied ranges. This study highlights the utility of statistical analysis in elucidating material property relationships, contrasting with the less interpretable nature of machine learning models. The findings provide valuable insights into the role of Cu content in MGs and demonstrate the importance of traditional statistical approaches for material characterization.

Morphological, structural, and electrochemical properties of ZnO- and Ni-doped ZnO nanocrystals formed using different reducing agents in the chemical co-precipitation technique

Morphological, structural, and electrochemical properties of ZnO- and Ni-doped ZnO nanocrystals formed using different reducing agents in the chemical co-precipitation technique

How is graphene influencing the electronic properties of NiO-TiO2 heterojunction?

Abstract We synthesized a new nanocomposite bearing nitrogen-doped graphene as a carbon additive to the nickel oxide nanoparticles-titanium dioxide nanotubes heterojunction. The main purpose was the comparison of its structural and electronic properties, hence potential applications, with its undoped, reduced graphene oxide homolog. The beneficial effect of graphene on TiO2 heterojunctions is an accepted fact in the materials science field, mainly in favor of the nitrogen-doped one. Our data show that both graphenes have little influence on the band offset values of the NiO-TiO2 heterojunction. Still, the presence of reduced, undoped graphene oxide allows an improved electron transfer process from titania, causing a better charge carriers’ separation. This correlates well with their observed photocatalytic activity under visible light exposure, for the degradation of four emerging contaminant pollutants (amoxicillin, acetaminophen, ibuprofen, and β-estradiol). In addition, the band alignment of the NiO-TiO2 heterojunction with graphenes, and the corrected thermodynamic potentials of the organic pollutants explain well the observed photocatalytic behavior.

Gradual Solvent Quality Changes Induce Abrupt Changes in Interfacial Layer, Dispersion Structure, and Physical Properties of Polymer Nanocomposites

Gradual Solvent Quality Changes Induce Abrupt Changes in Interfacial Layer, Dispersion Structure, and Physical Properties of Polymer Nanocomposites

First‐Principles Calculations to Investigate the Structural, Mechanical, Electronic, Optical and Thermal Properties of Disilicides Materials UT2Si2 (T = Ru, Rh, and Pd)

Different physical features of UT2Si2 (T = Ru, Rh, Pd) are investigated using ab initio methods. The examined lattice parameters are closely aligned with the experimental data. The negative cohesive energy ensures the chemical stability of the UT2Si2 (T = Ru, Rh, Pd). The mechanical stability of UT2Si2 (T = Ru, Rh, Pd) is ensured from the positive elastic constants. Very large bulk and Young's moduli of URu2Si2, and URh2Si2 ensures their high resistance to volume and longitudinal deformation. Whereas the lower Young's modulus (E) for UPd2Si2 suggests its heightened capacity to resist thermal shock resistance. The high machinable index of UPd2Si2 compared to URu2Si2 and URh2Si2 confirm its more damage‐tolerant and high elastic behavior and probable industrial applications. All the phases exhibit elastic anisotropy and ductile nature. Metallic features as well as mixture of covalent and ionic bonding are observed from electronic properties. Furthermore, the investigation on optical properties suggests the potential use of UT2Si2 (T = Ru, Rh, Pd) in anti‐reflection coatings, UV detectors, and optoelectronic devices due to their notable peaks in the UV energy range. The thermodynamic parameters such as Debye temperature as well as minimum thermal conductivity indicate the potential utility of these compounds in thermal barrier coating materials.

Nanocrystallization tuning of structural, thermoelectric and electrical properties of SrTiO3-doped vanadate glasses

Glass-ceramic nanocrystals (GCNs) were obtained by annealing parent SrTiO3-V2O5 (SV) glasses prepared using the melt-quenching technique at the crystallization temperature, Tc. The amorphous nature and glassy behavior of the quenched glasses were confirmed by XRD, DSC and FTIR spectroscopy. In the heat-treated samples, the crystal size was found to range from 40 to 80 nm for all studied samples. It was observed that as the SrTiO3 content in the GCNs increased, density (d) steadily rose. The change of vanadium ions concentration(C) has the predominant role for changing Seebeck coefficient in both glass and GCNs samples. The nanocrystallization process at temperatures close to the onset of Tc, lasting for one hour, notably increased the electronic conductivity of the initial glasses. Consequently, the modification in nanostructure resulted in enhanced conductivity. In comparison to the original glasses, the final materials demonstrated significantly improved electrical conductivity. The accumulation of V4+-V5+ pairs at the formed interlayer zones between nanocrystallites and the glassy phase is accountable for electron hopping in the current system, which is markedly higher than in the glassy matrix. The formed nanocrystallites play a crucial role in augmenting the conductivity of such nanomaterials. The maximum obtained value of the power factor (PF) is 0.9 × 10−4 mW/mk2 for the glass sample (x = 20) reflecting a very low thermoelectric power conversion efficiency while in GCNs, the PF values were well-enhanced to 0.6 mW/m.K2 at x = 20.

Thermoplastic Elastomers and Their Physical Gels Electrospun into Tunable Microfibrous Nonwoven Mats: Structure Formation and Property Enhancement

AbstractThermoplastic elastomers (TPEs) based on styrenic block copolymers constitute excellent examples of self‐networking macromolecules that are employed in a wide range of contemporary technologies as molded parts. In such applications, these TPEs exist as dense (nonporous) films or other shapes. Here, it is first demonstrated that a series of commercial TPEs possessing comparable compositions can be electrospun from solution to form microfibers that are arranged into nonwoven mats that are breathable. An important consideration for microfiber formation is the copolymer molecular weight, which regulates i) the viscosity of the parent solution prior to electrospinning, ii) the ability of these copolymers to self‐assemble during electrospinning, iii) the microfiber morphology, and iv) the mechanical properties of the resultant microfibers. The addition of a midblock‐selective aliphatic oil to these TPEs yields thermoplastic elastomer gels (TPEGs), wherein the copolymer morphology and mechanical properties become highly composition‐tunable. Electrospinning TPEGs from a binary oil+solvent solution introduces a micelle inversion mechanism that begins with an oil‐rich micellar core and ends with a styrene‐rich micellar core, required for network stabilization, as the solvent dries during microfiber solidification. This work has implications for the production of controllably low‐modulus microfibrous materials possessing modestly improved toughness but exceptional extensibility and enhanced optical transparency.

Synthesis, Structure, Photoluminescence, and Optical Properties of (Co/B) Co‐Doped ZnO Nanoparticles

Synthesis, Structure, Photoluminescence, and Optical Properties of (Co/B) Co‐Doped ZnO Nanoparticles

Highly efficient removal of uranium (VI) from aqueous solutions by APTES/ATP

Abstract Uranium-containing wastewater poses a significant threat to both the ecological environment and human health. Adsorption is a crucial method for purifying uranium wastewater. Using 3-Aminopropyltriethoxysilane (APTES) to modify attapulgite (ATP), we successfully prepared a cost-effective and high-performance adsorbent material, APTES-modified attapulgite (APTES/ATP). This material was utilized for the purification of uranium-containing wastewater. Characterization techniques were employed to study the structure and surface properties of the material. The adsorption performance of the material was investigated using single-factor experiments. The adsorption isotherms, kinetics, and thermodynamics were also studied and discussed. The results indicated that APTES/ATP exhibited an adsorption capacity of 382.13 mg·g⁻¹ for uranium at room temperature. The adsorption process followed the Langmuir adsorption model and pseudo-second-order kinetics, indicating that the adsorption of uranium by the material was a monolayer chemisorption. Adsorption thermodynamics revealed that the process was endothermic and spontaneous. The adsorption mechanism primarily involved electrostatic attraction and interactions between -NH₂, Si-O, and -OH groups with uranium. In summary, the prepared APTES/ATP demonstrated excellent adsorption capacity for uranium and shows promise for the purification of uranium-containing wastewater.

External oxide layers formed by the oxidation procedure in FeMnSi and FeMnSiCr shape memory alloys and their effects

Abstract Shape memory alloys are exposed to high temperatures to improve their properties and functionality. Through this process, oxidation inevitably occurs due to the presence of oxygen in the environment, which interacts with the alloying elements. Oxidation adversely affects the hardness of alloys, leading to a decline in their overall quality. In this study, the oxidation behavior parameters of FeMnSi and FeMnSi-Cr alloys and the oxide layers formed during this process were investigated in Fe-based alloys with high usage potential. Both non-isothermal and isothermal oxidation processes were applied to alloys and the oxidation parameters were determined. Subsequently, the changes in the crystal structure, microstructure, and magnetic properties of the alloys subjected to isothermal oxidation at 400-500-600-700-800 °C were investigated. It was found that the oxidation behavior of both alloys intensified with rising oxidation temperatures, as evidenced by crystal structure and microstructural analyses, which indicated deeper penetration into the alloys at elevated temperatures. Furthermore, an increase in magnetization values was noted alongside the oxidation process. A comparison of the oxidation characteristics between FeMnSi and FeMnSi-Cr alloys revealed that the oxidation parameters for the chromium-doped FeMnSi alloy were comparatively lower.