Amorphous Behavior Research Articles

On the Surface Property–Oxidation Relationship in Refractory High‐Entropy Alloys

In this study, oxidation behavior in as‐cast polycrystalline HfNbTaTi3, HfNbTaTiZr, HfMoTaTiZr, and NbMoTaTiZr refractory high‐entropy alloys (RHEAs), and the amorphous form of NbMoTaTiZr RHEA, is investigated. Herein, the surfaces of samples undergoing static oxidation experiments at 700, 800, and 900 °C using scanning electron microscopy, energy‐dispersive X‐Ray spectroscopy, X‐Ray photoelectron spectroscopy, and X‐Ray diffraction are explored. In the corresponding findings, the presence of three different oxidation behaviors in the studied RHEAs is shown: formation of a non‐protective scale, powderization and pesting of the sample, and a distinct amorphous oxidation behavior compared to its polycrystalline counterpart. Notably, Nb appears to induce a detrimental effect on the oxidation properties of samples due to the high ratio of volume change between the oxide and the metal. In the current findings, it is also evidenced that Mo can cause catastrophic failure in RHEAs that lack a protective oxide layer. Overall, the results constitute a step forward in enhancing the understanding of oxidation behavior in RHEAs and developing novel oxidation‐resistant RHEAs.

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.

ZnS and CdS nano thin films – A comprehensive analysis of structural, morphology and optical properties for photovoltaic applications

The current study is on the deposition of Zinc Sulfide and Cadmium Sulfide thin films by chemical bath deposition (CBD) technique. The deposited films were annealed at 200 °C and 350 °C in vacuum system. The Structural, Surface morphology, elemental composition and Optic analysis were performed by XRD, SEM, EDX, PL and optical transmission spectra. The XRD confirmed the formation of ZnS and CdS which revealed a broad spectrum in the low 2θ region due to its amorphous behaviour. The average optical transmission spectrum of ZnS lies between 65 % and 80 % and CdS lies between 50 and 60 %. The optical band gap of both the annealed films was decreasing with increase in temperature. The higher optical transmittance observed from emission spectra of PL analysis can contribute better performance and proved that the annealed ZnS and CdS thin films are applicable for photovoltaic applications.

Electrospun Quasi‐Composite Polymer Electrolyte with Hydoxyl‐ anchored Aluminosilicate Zeolitic Network for Dendrite Free Lithium Metal Batteries

All‐solid‐state lithium metal batteries have reshaped emerging safe battery technologies. However, their low metal ion transport and unstable electrode electrolyte interface make their mass production a huge question. To bridge the emerging solid state and traditional liquid electrolytes, we focus on Quasi‐Composite Polymer electrolytes (QCPE). Herein, we develop QCPE with active 3D alumino‐silicate zeolitic ion conduction pathways embedded in a polymer matrix using two techniques‐ solution casting and electrospinning. Electrospun QCPE outperforms Solution cast QCPE by achieving high amorphous behavior. Prompt elimination of solvent during electrospinning decreases bulk resistance and increases its ionic conductivity. The Zeolitic pathway anchored by hydroxyl groups of PVA polymer acts as highway for Li+ ions. It exhibits highly stable platting stripping vs Li+/Li for 450 hrs with low overpotential thereby confirming the interfacial compatibility and dendrite‐free cycling at lithium metal anode. Controlled lithium‐ion nucleation regulated by evenly distributed zeolitic pathway is an interesting front of this work. To test QCPE’s performance in Lithium metal battery (LMB), the electrospun QCPE is used to fabricate LMB with LiFePO4 cathode. This battery system delivered a high capacity of 155 mAh g‐1 at 0.1C. In addition to the high performance, electrospun QCPE production is scalable at an industrial scale.

Photon shielding properties of oxyfluoride aluminophosphate glass added with Sb2O3 by using PHITS Monte Carlo simulation and experimental methods

The glass formula (65-x)P2O5–5CaF2–10NaF–10KF–10AlF3-xSb2O3 (x = 0, 5, 10, 15 mol%) were produced by melt quenching technique for photon shielding application. The present glasses were investigated for the physical, structural, optical, gamma ray and x-ray shielding properties. The results revealed that the density increased when concentrations of Sb2O3 increased, the Fourier Transform Infrared (FTIR) and the X-ray diffraction (XRD) results illustrated the functional groups of vibrations, and confirmed the amorphous behavior, respectively. The transmission spectra of present glasses showed higher transparency than x-ray windows. The comparative studies of gamma-ray between experiment and theoretical, the mass attenuation coefficients (MAC), effective atomic number (Zeff), and effective electron density (Neff) were increased with increasing concentration of Sb2O3. On the other hand, the half value layer (HVL) was decreased. The energy absorption buildup factor (EABF) and exposure buildup factor (EBF) of dopant Sb2O3 in present glass were calculated and discussed in terms of energy and concentration of Sb2O3. As a result of using the X-ray source, the HVL was decreased with a rise in Sb2O3 contents. HVL value at 15 mol% of Sb2O3 concentration is higher than the standard materials at 120 kVp. The Sb2O3 glass systems can be a candidate for radiation shielding material.

Dynamic pressure-induced amorphous transition and crystallization behavior of 4-methylpyridine

The phase transitions of 4-methylpyridine (4MP) were studied under static pressure and dynamic pressure by in situ Raman spectroscopy. Under static compression, 4-methylpyridine underwent three phase transitions: a liquid to crystal I transition at 0.44 GPa; followed by transformation into crystal II at 2.17 GPa and crystal III at 10.36 GPa. Under dynamic compression, 4-methylpyridine was compressed into an amorphous phase as the pressure increased from 0.36, 0.38, and 0.33 GPa to 4.42, 6.80, and 11.53 GPa within 5 ms, respectively. Through the fitting of partial Raman peak linewidth with pressure, the compression rate has a significant effect on the disorder degree of crystal structure. During the pressure relief process, the amorphous 4-methylpyridine transformed into a new crystal Ⅰ’ at 2.40 GPa, and then returned to the initial liquid state at roughly 0.58 GPa. The phase transitions of 4-methylpyridine dynamic pressure can be explained by the faster compression rate that drives systems to break chemical equilibrium and generate a new phase.

Characterization, phytochemical profiling, antioxidant, and cytotoxicity of underutilized medicinal plants and composite flour

In this investigation, three medicinal plant powders and a composite flour developed from them were analyzed. FESEM/EDS illustrated irregularly shaped particles in the plant powders except for Withania, which had round to oval shape particles. XRD analysis displayed a semi-crystalline nature of powders, except for Asparagus, which showed amorphous behavior. Both methanol and ethanol plant extracts exhibited significantly higher antioxidants, total phenols, and cell viability. Amongst, optimized composite flour (OCF) methanolic extract demonstrated the highest total phenolic content (69.2 ± 0.11 μg GAE/ml), potent cell viability against A549 cells (3.35 ± 0.15% at 50 μg/ml), and strong free-radical scavenging activity (48.89 ± 0.67 at 200 μg/ml). GCMS and FTIR analyses of the methanolic extracts demonstrated the presence of essential phytoconstituents and functional groups. In silico studies of the phytocomponents, ethyl isoallocholate, 3-Deoxy-d-mannoic lactone, and 4,5-Diamino-2-hydroxypyrimidine suggested good binding affinity against BAX, P53, and EGFR proteins with no toxicity and a good drug score.

X-ray photoelectron spectroscopy, structural, and radiation shielding properties for transparent borosilicate glasses

The current work investigates the impact of SrO content on the structural, physical, and shielding properties of xSrO-10TiO2–10SiO2-(65-x) B2O3, where (15 ≤ x ≤ 30) glasses. X-ray diffraction (XRD), X-ray photoelectron spectroscopy (XPS), Fourier transform infrared (FTIR), and radiation shielding features were utilized to investigate the samples’ features. XRD results affirmed the amorphous behavior. The FTIR values presented many peaks attributed to SiO2 and B2O3. The Sr30B50 sample (3.048 g/cm3) showed the highest density, followed by Sr25B55 (2.936 g/cm3), Sr20B60 (2.720 g/cm3) and Sr15B65 (2.679 g/cm3). The XPS analysis of Ti 2p core level spectra reveals that Ti ions exist in both Ti4+ and Ti3+ oxidation states, with the content of Ti4+ increasing with the SrO ratio in the glass sample. The XPS analysis of O 1s core level spectra revealed that the number of non-bridging oxygen atoms is enhanced with an increase in SrO content, indicating the weakening of the glass structure. Furthermore, neutron and photon shielding properties were calculated theoretically using Phy-X software. The gamma shielding properties were enhanced with increasing SrO, while the neutron attenuation was equivalent to water. For example, the fast neutron removal cross-section (FNRCS) values are 0.101, 0.098, 0.102, and 0.101 cm−1 for Sr15B65, Sr20B60, Sr25B55, and Sr30B50, respectively. The findings suggest that the SrO improved radiation shielding properties while decreasing glass stability.

Novel Fe–B–P–C–Cu–Co amorphous/nanocrystalline alloys with excellent comprehensive performance via Co substitution for Fe

The amorphous formation ability, thermal properties, crystallization behavior, magnetic properties, resistivity and bending ductility of Fe84.5-xB12P2C1Cu0.5Cox (x = 0, 4, 8) alloys were systematically investigated. It is found that the substitution of Fe by Co promotes the transformation of the as-spun alloys from a completely amorphous structure to an amorphous/nanocrystalline dual-phase structure, which is related to the differences in the interactions between the involved atoms. The saturation magnetization of alloys increases with increasing Co content and can be increased to 1.93 T at x = 8 by heat treatment, but excessive substitution of Co for Fe deteriorates the coercivity and bending ductility due to the pre-existing α-Fe(Co) grains. The resistivity is positively correlated with the disorder of structure, and the as-spun alloy with x = 4 exhibits a high resistivity of 136.2 μΩ cm. As a result, the annealed Fe80.5B12P2C1Cu0.5Co4 alloy with excellent soft magnetic properties (Ms = 1.81 T, Hc = 7.8 A/m) and good bending ductility in combination with high resistivity has potential for application in the field of electronic devices.

Performance-enhanced intrinsic polarization-sensitive organic photodetectors by molecular interaction modulation

Polarization-sensitive organic photodetectors (OPDs) are increasingly paid attention for their broad application prospect. However, it is extremely difficult to achieve highly sensitive detection of polarized light for most organic semiconductor polymers with intrinsic isotropic amorphous behavior. In this study, the performance-enhanced intrinsic anisotropic all-polymer bulk heterojunctions (BHJs) are obtained by constructing molecular fluorination engineering in the fused-ring backbone of the acceptor polymer. The molecular orientation, alignment, and packing can be effectively optimized during the floating-film formation process without using any additives and post-treatments. The outstanding intrinsic polarization-sensitive photodetection performance with a very high photocurrent dichroic ratio of 3.73, a specific detectivity of 1.3 × 1011 Jones at 0 V, and a broad linear dynamic range of 120 dB is achieved for the optimum-fluorine-content self-assembly all-polymer organic BHJ film. The superiorities of self-powered capability, fast response, and high-contrast imaging demonstrate that the backbone fluorination for acceptor polymers is conducive to achieving excellent structural regularity and can endow the intrinsic polarization-sensitive all-polymer OPDs with more demanding polarized-light detection ability.

Ionogels based on protic ionic liquid - lithium salt mixtures

The effect of the addition of lithium nitrate on the liquid range and electrical conductivity of mixtures of a protic ionic liquid, ethylammonium nitrate (EAN) with LiNO3 is reported in this work. Moreover, changes in these properties upon confinement in silica-based matrices are also analysed and related to variations on the microstructure of the mixtures. Our results show that gelation of the mixtures induces amorphous behaviour in all the samples, but no significant changes in the thermal stability are detected. However, important differences on the electrical conductivity of the liquid and gel states of the mixtures were observed. While this magnitude decreases with the addition of salt in the liquid samples for all the temperatures it increases at low concentrations of LiNO3 up to a maximum in the gelled samples with the lowest concentration of added salt (0.1 mol of salt by kg of EAN). High resolution magic angle spinning (HRMAS) NMR shows that the addition of lithium nitrate increases the mobility (both rotational and translational motion) of the cation EA+ within the ionogel and the diffusion of the cation provides evidence of the presence of two different populations of the same molecules experiencing two distinct apparent diffusion coefficients (bi-exponential decay of magnetization in diffusion NMR experiments), while it is mono-exponential in the pure ionic liquid. The Li+ cation is shown to display a higher mobility (both rotational and translational motion) in the ionogel than in the neat ionic liquid. The frustration of the formation of solvation complexes due to the confinement is suspected to be behind this behaviour.

Enhanced Photocatalytic and Photovoltaic Performance Arising from Unconventionally Low Donor-Y6 Ratios.

Development of both organic photovoltaics (OPVs) and organic photocatalysts has focused on utilizing the bulk heterojunction (BHJ). The BHJ promotes charge separation and enhances the carrier lifetime, but may give rise to increased charge traps, hindering performance. Here, high photocatalytic and photovoltaic performance is displayed by electron donor-acceptor (D-A) nanoparticles (NPs) and films, using the nonfullerene acceptor Y6 and polymer donor PIDT-T8BT. In contrast to conventional D-A systems, the charge generation in PIDT-T8BT:Y6 NPs is mainly driven by Y6, allowing a high performance even at a low D:A mass ratio of 1:50. The high performance at the low mass ratio is attributed to the amorphous behavior of PIDT-T8BT. Low ratios are generally thought to yield lower efficiency than the more conventional ≈1:1 ratio. However, the OPVs exhibit peak performance at a D:A ratio of 1:5. Similarly the NPs used for photocatalytic hydrogen evolution show peak performance at the 1:6.7 D:A ratio. Interestingly, for the PIDT-T8BT:Y6 system, as the polymer proportion increases, a reduced photocatalytic and photovoltaic performance is observed. The unconventional D:A ratios provide lower recombination losses and increased charge-carrier lifetime with undisrupted ambipolar charge transport in bulk Y6, enabling better performance than conventional ratios. This work reports novel light-harvesting materials in which performance is reduced due to unfavorable morphology as D:A ratios move toward conventional ratios of 1:1.2-1:1.

Customizable Three-Dimensional Printed Earring Tap for Treating Affections Caused by Aesthetic Perforations.

This work aimed to develop a three-dimensional (3D) wearable drug-loaded earring tap to treat affections caused by aesthetic perforations. The initial phase involved a combination of polymers to prepare filaments for fused deposition modeling (FDM) 3D printing using a centroid mixture design. Optimized filament compositions were used in the second phase to produce 3D printed earring taps containing the anti-inflammatory naringenin. Next, samples were assessed via physicochemical assays followed by in vitro skin permeation studies with porcine ear skin. Two filament compositions were selected for the study's second phase: one to accelerate drug release and another with slow drug dissolution. Both filaments demonstrated chemical compatibility and amorphous behavior. The use of the polymer blend to enhance printability has been confirmed by rheological analysis. The 3D devices facilitated naringenin skin penetration, improving drug recovery from the skin's most superficial layer (3D device A) or inner layers (3D device B). Furthermore, the devices significantly decreased transdermal drug delivery compared to the control containing the free drug. Thus, the resulting systems are promising for producing 3D printed earring taps with topical drug delivery and reinforcing the feasibility of patient-centered drug administration through wearable devices.

Polymorphic states investigations in thermal conductivity of 1-fluoroadamantane

The temperature dependencies of the thermal conductivity coefficient, κ(T), in 1-fluoroadamantane were investigated for two different orientationally-disordered states. In the first one, κ(T) exhibits a crystalline character with a typical maximum and two anomalous regions marked at higher temperatures. Here, the low-temperature power-law dependence is reduced due to a relatively large contribution of dislocations and defects in the polycrystalline sample. Above 196 K, there is an anomalous plateau in thermal conductivity resulting from the presence of an intermediate centrosymmetric state. Further, a significant increase in κ occurs above 234 K, resulting from a phase transition to a high-temperature disordered cubic phase. Subsequent cooling of the sample leads to an irreversible transition towards a disordered state resulting in a κ(T) dependence corresponding to an amorphous material behavior. The primary anomaly at 196 K disappears, while the second one associated with the phase transition at 227 K shifts towards lower temperatures. The irreversibility of this transformation is also verified by scanning microscopy images. Thermal conductivity in both phases has an additional contribution of an Arrhenius type in their temperature dependences.

Structural, mechanical, optical, and radiation shielding properties for borotellurite glasses

In this work, six glass samples previously fabricated were used to prepare three glass systems by the melt-quench technique. X-ray diffraction and Fourier transform infrared studied the structure of refabricated glasses. At the same time, the Makishima–Mackenzie model was used to assess the elastic moduli for refabricated glasses. The optical properties of refabricated glasses were calculated based on UV–Vis absorption. The radiation shielding features were evaluated based on the Phy-X and SRIM programs. The X-ray diffraction results exhibited the amorphous behavior for all refabricated glasses, while the Fourier transform infrared revealed several bands related to TeO2 and B2O3. The band gap values for TBBBSr, TBBBZn, and TBBBCd glasses are 3.439, 3.236, and 3.195 eV, respectively. The Young modulus values are 59.368, 57.843, and 56.358 GPa for TBBBSr, TBBBZn, and TBBBCd glasses, which indicate superior the TBBBSr glass sample on other glasses in mechanical properties. The mechanical, optical, and Fourier transform infrared results showed high compatibility. In contrast, the TBBBCd glass recorded the highest density and gamma-ray shielding properties; for example, the linear attenuation coefficient values at 15 MeV are 0.222 cm−1 for TBBBCd, 0.214 cm−1 for TBBBZn, and 0.188 cm−1 for TBBBSr. While, the TBBBZn glass showed the highest neutron shielding feature; for example, the fast neutron removal cross section is 0.088, 0.091, and 0.092 cm−1 for TBBBSr, TBBBZn, and TBBBCd, respectively. On the other hand, the TBBBSr displayed the highest shielding features for charged particles. In conclusion, the TBBBSr glass can be nominated for radiation shielding applications based on its superior mechanical properties and ability to stop charged particles.

X-ray attenuation performance of a newly synthesized tellurium based lead-free radiation shielding glass system

The lead-free quaternary glass systems containing B2O3–CaO–ZnO–TeO2 were synthesized using the traditional melt-quenching method. XRD analysis confirmed that the TeZnCaB glass system exhibited an amorphous behaviour. The density of the glass samples was increased from 3.48 g/cc to 4.08 g/cc by increasing the TeO2 concentration from 20 to 45 mol%. From UV–visible spectroscopy, it was observed that direct and indirect energy band gaps decreased with increasing the TeO2 concentration whereas the refractive index increased. TEM analysis revealed the amorphous behaviour along with nanocrystals present in the glass sample. X-ray attenuation measurements were performed to assess the radiation shielding properties of the lead-free glass system and observed that the radiation shielding capacity was increased with the TeO2 concentration. The best lead equivalent thickness was 2.02 mm for the sample with 45% TeO2 and these glasses could be promising materials for medical diagnostic applications.

Investigation and optimization of In-Vitro behaviour of Perovskite barium titanate as a scaffold and protective coatings

The piezoelectric effect is widely known to have a significant physiological function in bone development, remodeling, and fracture repair. As a well-known piezoelectric material, barium titanate is particularly appealing as a scaffold layer to improve bone tissue engineering applications. Currently, the chemical bath deposition method is used to prepare green synthesized barium titanate coatings to improve mechanical and biological characteristics. Molarity of the solutions, an essential parameter in chemical synthesis, is changed at room temperature (0.1–1.2 Molar) to prepare coatings. The XRD spectra for as deposited coatings indicate amorphous behavior, while polycrystalline nature of coatings is observed after annealing (300 °C). Coatings prepared with solutions of relatively low molarities, i.e. from 0.1 to 0.8 M, exhibit mixed tetragonal – cubic phases. However, the tetragonal phase of Perovskite barium titanate is observed using solution molarities of 1.0 M and 1.2 M. Relatively high value of transmission, i.e. ∼80%, is observed for the coatings prepared with high molarities. Band gap of annealed coatings varies between 3.47 and 3.70 eV. For 1.2 M sample, the maximum spontaneous polarization (Ps) is 0.327x10−3 (μC/cm2) and the residual polarization (Pr) is 0.072x10−3 (μC/cm2). For 1.2M solution, a high hardness value (1510 HV) is recorded, with a fracture toughness of 28.80 MPam−1/2. Low values of weight loss, after dipping the coatings in simulated body fluid, is observed. The antibacterial activity of BaTiO3 is tested against E. coli and Bacillus subtilis. Drug encapsulation capability is also tested for different time intervals. As a result, CBD-based coatings are a promising nominee for use as scaffold and protective coatings.

Protein concentrates from plain, aromatic and pigmented rice cultivars: Functional, thermal and morphological characterization

Protein is a vital nutrient required for growth and development of human population. It is well recognised that a significant cause of malnutrition is a lack of protein in human diet. Plant based proteins are becoming an excellent substitute for meat proteins in the development of functional foods at a fair price. When it comes to plant-based sources of high-quality protein, rice is regarded as a useful option because of its hypoallergenic properties, adequate amino acid balance, and high protein content. Therefore, protein concentrates were obtained from plain (SR-4, K-39), aromatic (Mushq Budij) and pigmented (Zhag) rice cultivars of Kashmir. Significant (p<0.05) difference was observed in protein (70.40–74.23 g/100 g) and ash (2.90–3.50 g/100 g) contents of protein concentrates isolated from different rice cultivars. Zhag protein had the lowest ‘L’ value (40.20). However, it had the highest emulsifying activity (47.29 m2/g) and emulsion stability index (13.38 min) at neutral pH. Moreover, water absorption capacity was highest for K-39 protein (1.90 g/g). Zhag protein had the highest protein solubility and foaming stability under acidic pH conditions. Zhag protein had the highest denaturation temperature (81.70 °C) and denaturation enthalpy (9.55 Jg−1). No sharp peaks were observed in the X-ray diffractogram (XRD), indicating amorphous behaviour of protein powder. Pearson's correlation revealed positive correlation between emulsifying activity indices (EAI) at pH 7 and protein solubility at pH 8 (r = 0.955, p<0.05). Surface hydrophobicity (SH) of RPCs was found to be positively correlated with EAI at pH 3 (r = 0.991, p<0.01) and foaming capacity (FC) at pH 8 (r = 0.994, p<0.01), respectively. It can be concluded from the present study that protein concentrate from pigmented rice cultivar was superior to other samples in terms of functionality and thermal attributes.

Eco-friendly Synthesis and Characterization of Amorphous Nanosilica from Rice Husk

Background: A significant amount of rice production waste is rice husk. It is not humifiable and turns into a significant environmental pollutant if not properly utilized. Rice husk contains silica nanoparticles, which is a major inorganic component. High purity amorphous silica nanoparticles can thus be produced using simple thermo-chemical procedures without polluting the environment by cutting out the release of carbon dioxide during the process. Methods: A study was carried out to extract amorphous silica nanoparticles from rice husk ash using an environmentally benign chemical process. Utilising a variety of material characterization techniques viz., X-ray diffraction (XRD), fourier-transform infrared spectroscopy (FT-IR), field emission scanning electron microscope (FESEM), energy dispersive X-ray spectroscopy (EDS) and Particle size analyser (PSA), the extracted nanoparticles properties were confirmed. Result: The amorphous behaviour of the silica sample was confirmed using transmission electron microscopy-selected area electron diffraction patterns and X-ray diffraction analyses, whilst siloxane and silanol groups were primarily discovered using Fourier-transform infrared spectroscopy. Images obtained using scanning electron and transmission electron microscopy showed initial nanoparticles to be present along with secondary microparticles, possibly as a result of their agglomeration. The extracted amorphous silica has particles with an average diameter of 35 nm. This synthesized silica nanoparticles can be used in agriculture, nano-additives, microelectronics, sensors and in other fields.

Atomic insight into mechanical behavior of AuPt alloys

AuPt alloys are widely applied in electronics, aerospace, and precision equipment fields. A thorough understanding of the mechanical behavior of AuPt alloys is critical for their potential applications. Here, we leverage molecular dynamics (MD) method to for the first reveal the effects of microstructure and temperature on mechanical behavior of AuPt alloys from atomic level. The nanoindentation of monocrystalline (MC), nanotwinned (NT), and nanocrystalline (NC) AuPt alloys are performed. The results demonstrate that the mechanical properties of the MC AuPt alloy are excellent at 77 K because of dislocation strengthening while poor at high temperature due to amorphous behavior. The introduction of twinning boundary (TB) greatly improves the mechanical properties of AuPt alloy by preventing the stress spread and promoting dislocation activity. The mechanical behavior of NC AuPt alloy is strongly dependent on grain size. With increasing average grain size, the dominant plastic deformation mechanism of NC AuPt alloy changes from GB migration to dislocation motion and then to GB destruction. An appropriate grain size should be selected to inhibit GB migration or GB destruction, thereby achieving the enhancement of NC AuPt alloy through dislocation strengthening. This work provides an important theoretical basis for the subsequent design of AuPt alloys with desirable mechanical performances to extend the application prospects of noble metals.