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Catalytic ozonation with metal oxides is of interest for advanced water treatment technology. The amount of active oxygen-containing radicals produced is a primary objective of this process. Fe2O3 is a widely used catalyst because of its high performance. In this study, Fe2O3/SBA-15 was synthesized and characterized. The results revealed that Fe2O3/SBA-15 was a nano-/mesoporous material with high-order hexagonal array structures and exhibited greater catalytic performance than Fe2O3 in ozonation processes. To investigate the role of the Fe2O3/SBA-15 surface in O3 decomposition, the kinetic constant was measured, and the interfacial reactions were discussed. Compared with Fe2O3, Fe2O3/SBA-15 significantly increased the formation of hydroxyl radicals (•OH) and the efficient utilization of O3 in the catalytic O3 decomposition process. The SBA-15 support decreased the O3 self-decomposition rate during catalytic ozonation with Fe2O3/SBA-15, which resulted in increased formation of •OH via the reaction between O3 and Fe2O3. From a practical point of view, Fe2O3/SBA-15 is an efficient green ozonation catalyst for water treatment. [ABSTRACT FROM AUTHOR]

Graphene has been considered an ideal reinforcement in aluminum alloys with its high Young's modulus and fracture strength, which greatly expands the application range of aluminum alloys. However, the dispersion of graphene and the interfacial reaction between graphene and the aluminum matrix limit its application due to elevated temperature. Friction stirring processing (FSP) is regarded as a promising technique to prepare metal matrix composites at lower temperatures. In this paper, FSP was used to prepare graphene-nanoplates-reinforced aluminum composites (GNPs/Al). The corresponding effects of the process parameters and graphene content on GNPs/Al were thoroughly studied. The results showed that plastic strain, heat input, and graphene content were the key influencing factors. Large degrees of plastic strain can enhance the dispersion of graphene by increasing the number of stirring passes and the ratio of stirring to welding velocity, thereby improving the strength of GNPs/Al. Low heat input restricts the plastic flow of graphene in the matrix, whereas excessive heat input can promote interfacial reactions and lead to the formation of a more brittle phase, Al4C3. This is primarily associated with the stirring velocity and welding velocity. High graphene content levels can improve the material strength by refining the grain size, improving the load transfer ability, and acting as a precipitate to prevent dislocation movement. These findings make a contribution to the development of advanced aluminum alloys with graphene reinforcement, offering broader application potential in industries. [ABSTRACT FROM AUTHOR]

Nickel oxide (NiOx)‐based inverted perovskite solar cells stand as promising candidates for advancing perovskite photovoltaics towards commercialization, leveraging their remarkable stability, scalability, and cost‐effectiveness. However, the interfacial redox reaction between high‐valence Ni4+ and perovskite, alongside the facile conversion of iodide in perovskite into I2, significantly deteriorates the performance and reproducibility of NiOx‐based perovskite photovoltaics. Here, potassium borohydride (KBH4) is introduced as a dual‐action reductant, which effectively avoids the Ni4+/perovskite interface reaction and mitigates the iodide‐to‐I2 oxidation within perovskite film. This synergistic redox modulation significantly suppresses nonradiative recombination and increases the carrier lifetime. As a result, an impressive power conversion efficiency of 24.17% for NiOx‐based perovskite solar cells is achieved, and a record efficiency of 20.2% for NiOx‐based perovskite solar modules fabricated under ambient conditions. Notably, when evaluated using the ISOS‐L‐2 standard protocol, the module retains 94% of its initial efficiency after 2000 h of continuous illumination under maximum power point at 65 °C in ambient air. [ABSTRACT FROM AUTHOR]

In order to study the microscopic reaction mechanism and kinetic model of Al/PTFE, a reactive force field (ReaxFF) was used to simulate the interface model of the Al/PTFE system with different oxide layer thicknesses (0 Å, 5 Å, 10 Å), and the thermochemical behavior of Al/PTFE at different heating rates was analyzed by simultaneous thermal analysis (TG-DSC). The results show that the thickness of the oxide layer has a significant effect on the reaction process of Al/PTFE. In the system with an oxide layer thickness of 5 Å, the compactness of the oxide layer changes due to thermal rearrangement, resulting in the diffusion of reactants (fluorine-containing substances) through the oxide layer into the Al core. The reaction mainly occurs between the oxide layer and the Al core. For the 10 Å oxide layer, the reaction only exists outside the interface of the oxide layer. With the movement of the oxygen ions in the oxide layer and the Al atoms in the Al core, the oxide layer moves to the Al core, which makes the reaction continue. By analyzing the reaction process of Al/PTFE, the mechanism function of Al/PTFE was obtained by combining the shrinkage volume model (R3 model) and the three-dimensional diffusion (D3 model). In addition, the activation energy of Al/PTFE was 258.8 kJ/mol and the pre-exponential factor was 2.495 × 1015 min−1. The research results have important theoretical significance and reference value for the in-depth understanding of the microscopic chemical reaction mechanism and the quantitative study of macroscopic energy release of Al/PTFE reactive materials. [ABSTRACT FROM AUTHOR]

Oxide inclusions in Ni-based superalloys play a crucial role in determining their mechanical properties, oxidation resistance, and corrosion resistance at high temperatures. In this paper, the source and formation mechanism of different types of oxide inclusions in a high-aluminum Ni-based superalloy were systematically studied. An automatic field emission scanning electron microscope equipped with an energy dispersive spectrometer and a self-designed superalloy inclusion analysis standard was utilized to quantitatively reveal the oxide inclusion characteristics of the high-aluminum Ni-based superalloy prepared via vacuum induction melting (VIM) and vacuum induction remelting (VIR) processes. The experimental results indicate that the typical oxide inclusions in the Ni-based superalloy before the VIR process are irregular MgO·Al2O3 inclusions with sizes of less than 2 μm. After the VIR process, the typical oxide inclusions in the Ni-based superalloy are also MgO·Al2O3 inclusions. However, these oxide inclusions can be classified into three categories: (i) endogenous irregular MgO·Al2O3 inclusions, less than 4.3 μm in size, inherited from the master alloy; (ii) several hundred-micron film-like MgO·Al2O3 inclusions generated as interface reaction products between the MgO crucible and melts; and (iii) millimeter-scale MgO·Al2O3 inclusions and several tens of microns of MgO inclusions from the exfoliation of the MgO crucible matrix. [ABSTRACT FROM AUTHOR]

The distribution of reinforcements and interfacial bonding state with the metal matrix are crucial factors in achieving excellent comprehensive mechanical properties for aluminum (Al) matrix composites. Normally, after heat treatment, graphene nanosheets (GNSs)/Al composites experience a significant loss of strength. Here, better performance of GNS/Al was explored with a hybrid strategy by introducing 0.9 vol.% silicon carbide nanoparticles (SiCnp) into the composite. Pre-ball milling of Al powders and 0.9 vol.% SiCnp gained Al flakes that provided a large dispersion area for 3.0 vol.% GNS during the shift speed ball milling process, leading to uniformly dispersed GNS for both as-sintered and as-extruded (0.9 vol.% SiCnp + 3.0 vol.% GNS)/Al. High-temperature heat treatment at 600 °C for 60 min was performed on the as-extruded composite, giving rise to intragranular distribution of SiCnp due to recrystallization and grain growth of the Al matrix. Meanwhile, nanoscale Al4C3, which can act as an additional reinforcing nanoparticle, was generated because of an appropriate interfacial reaction between GNS and Al. The intragranular distribution of both nanoparticles improves the Al matrix continuity of composites and plays a key role in ensuring the plasticity of composites. As a result, the work hardening ability of the heat-treated hybrid (0.9 vol.% SiCnp + 3.0 vol.% GNS)/Al composite was well improved, and the tensile elongation increased by 42.7% with little loss of the strength. The present work provides a new strategy in achieving coordination on strength–plasticity of Al matrix composites. [ABSTRACT FROM AUTHOR]

Diamond/aluminum composites have attracted significant attention as novel thermal management materials, with their interfacial bonding state and configuration playing a crucial role in determining their thermal conductivity and mechanical properties. The present work aims to evaluate the bending strength and thermal conductivity of CNT-modified Ti-coated diamond/aluminum composites with multi-scale structures. The Fe catalyst was encapsulated on the surface of Ti-coated diamond particles using the solution impregnation method, and CNTs were grown in situ on the surface of Ti-coated diamond particles using the plasma-enhanced chemical vapor deposition (PECVD) method. We investigated the influence of interface structure on the thermal conductivity and mechanical properties of diamond/aluminum composites. The results show that the CNT-modified Ti-coated diamond/aluminum composite exhibits excellent bending strength, reaching up to 281 MPa, compared to uncoated diamond/aluminum composites and Ti-coated diamond/aluminum composites. The selective bonding between diamond and aluminum was improved by the interfacial reaction between Ti and diamond particles, as well as between CNT and Al. This led to the enhanced mechanical properties of Ti-coated diamond/aluminum composites while maintaining acceptable thermal conductivity. This work provides insights into the interface's configuration design and the performance optimization of diamond/metal composites for thermal management. [ABSTRACT FROM AUTHOR]

The metallurgical quality control of magnesium (Mg) and Mg alloys in melting process is required to ensure a satisfied mechanical and corrosion performance, while the typical used steel crucible introduces impurities and interfacial interaction during melting process. Therefore, a systematic study about impurities diffusion and interfacial interaction between molten Mg and steel is necessary. In the present study, the interfacial reaction between molten AZ91D Mg alloy and mild steel during melting process was investigated with the melting temperatures of 700 °C, 750 °C and 800 °C. The results show that Al(Fe, Mn) intermetallic layer is the intermetallic primarily formed at the interfaces of AZ91D melt and mild steel. Meanwhile, Al8(Mn, Fe)5 is indexed between Al(Fe, Mn) and AZ91D. AlFe3C appears between the mild steel and Al(Fe, Mn) at 700 °C and 750 °C, but absent at 800 °C due to the increased solubility of carbon in Mg matrix. It is found that the growth of the intermetallic layer is controlled by diffusion mechanism, and Al and Mn are the dominant diffusing species in the whole interfacial reaction process. By measuring the thickness of different layers, the growth constant was calculated. It increases from 1.89(±0.03)×10-12 m² ·s-1 at 700 °C to 3.05(±0.05)×10-12 m² ·s-1 at 750 °C, and 5.18(±0.05)×10-12 m² ·s-1 at 800 °C. Meanwhile, the content of Fe is linearly increased in AZ91D with the increase of holding time at 700 °C and 750 °C, while it shows a significantly increment after holding for 8 h at 800 °C, indicating holding temperature is more crucial to determine the Fe content of AZ91D than holding time. [ABSTRACT FROM AUTHOR]

Abstract Nickel oxide (NiOx)‐based inverted perovskite solar cells stand as promising candidates for advancing perovskite photovoltaics towards commercialization, leveraging their remarkable stability, scalability, and cost‐effectiveness. However, the interfacial redox reaction between high‐valence Ni4+ and perovskite, alongside the facile conversion of iodide in perovskite into I2, significantly deteriorates the performance and reproducibility of NiOx‐based perovskite photovoltaics. Here, potassium borohydride (KBH4) is introduced as a dual‐action reductant, which effectively avoids the Ni4+/perovskite interface reaction and mitigates the iodide‐to‐I2 oxidation within perovskite film. This synergistic redox modulation significantly suppresses nonradiative recombination and increases the carrier lifetime. As a result, an impressive power conversion efficiency of 24.17% for NiOx‐based perovskite solar cells is achieved, and a record efficiency of 20.2% for NiOx‐based perovskite solar modules fabricated under ambient conditions. Notably, when evaluated using the ISOS‐L‐2 standard protocol, the module retains 94% of its initial efficiency after 2000 h of continuous illumination under maximum power point at 65 °C in ambient air.

Calcium hexaaluminate (CA6) materials have garnered attention for their potential use as lining materials in metallurgical furnaces during the steel-making process. The present work explored the effects of M2O5 (M = Nb, Ta) on the steel corrosion behaviour of calcium hexaaluminate combined with the evolution of physical properties. The introduction of M2O5 (M = Nb, Ta) was proved to be advantageous in mitigating the emulsification of CA6 material in the molten steel, and the increase in the densification of emulsion layer could prevent CA6 materials from further steel corrosion and penetration. The improved steel corrosion resistance of CA6 materials was attributed to the optimization of the physical properties facilitated by the formation of defects and the in situ phase. In addition, the reduction in the wettability between the CA6 materials and molten steel served to diminish the reactivity of the interface reaction. This work determined the corrosion behaviour and corrosion mechanism of the CA6 materials in molten steel and provided a new research route for designing CA6 materials with improved corrosion resistance to molten steel.

In view of the clogging problem associated with submerged entry nozzles (SEN) used for aluminum‐killed steel, the reaction behavior between the SEN and molten steel with high Al content with the influence of an external electric field is studied in this paper. The results showed that the application of an effective and positive voltage to the walls of the SEN would promote the decarburization of the SEN itself and the interfacial reaction between nozzle material and molten steel containing aluminum. On the contrary, these behaviors would be inhibited under the control of the negative voltage. Therefore, with the polarity of electric field applied on the SEN, it is necessary to determine whether the critical factor leading to clogging is the content of the Al2O3 inclusions or Al alloy content in the steel. [ABSTRACT FROM AUTHOR]

The relevant experiments and studies were conducted to address the metallurgical defects such as subcutaneous bubbles and slag inclusions occurring during the enamel steel continuous casting process. According to the high-temperature experimental results, calculations were made to determine the changes in viscosity and tension due to the steel reaction with the slag. Based on the experimental findings, there was a notable variation in the content of SiO2 and Al2O3 in the slag before and after the reaction. The concentration of the element Al in the steel melt significantly decreased, whereas the concentration of Ti showed a minimal change. These observations indicate that the reduction of SiO2 at the slag–steel interface is predominantly attributed to the role of Al. The calculation results showed that at 300 s of reaction time, the viscosity rapidly increased from 0.108 to 0.133 Pa·s and then slowly increased to 0.155 Pa·s; The interfacial tension rapidly decreased from its initial value of 1,380 mJ·m−2 to a minimum of 1,320 mJ·m−2, and it then slowly increased to an equilibrium state. Therefore, the main cause of the occurrence of porosity defects in the enamel steel continuous casting process is the reduction of interfacial tension between slag, steel, and gas caused by the reaction between the slag and steel, as well as the foaming of the slag.

Oxide inclusions in Ni-based superalloys play a crucial role in determining their mechanical properties, oxidation resistance, and corrosion resistance at high temperatures. In this paper, the source and formation mechanism of different types of oxide inclusions in a high-aluminum Ni-based superalloy were systematically studied. An automatic field emission scanning electron microscope equipped with an energy dispersive spectrometer and a self-designed superalloy inclusion analysis standard was utilized to quantitatively reveal the oxide inclusion characteristics of the high-aluminum Ni-based superalloy prepared via vacuum induction melting (VIM) and vacuum induction remelting (VIR) processes. The experimental results indicate that the typical oxide inclusions in the Ni-based superalloy before the VIR process are irregular MgO·Al2O3 inclusions with sizes of less than 2 μm. After the VIR process, the typical oxide inclusions in the Ni-based superalloy are also MgO·Al2O3 inclusions. However, these oxide inclusions can be classified into three categories: (i) endogenous irregular MgO·Al2O3 inclusions, less than 4.3 μm in size, inherited from the master alloy; (ii) several hundred-micron film-like MgO·Al2O3 inclusions generated as interface reaction products between the MgO crucible and melts; and (iii) millimeter-scale MgO·Al2O3 inclusions and several tens of microns of MgO inclusions from the exfoliation of the MgO crucible matrix.

Diamond/aluminum composites have attracted significant attention as novel thermal management materials, with their interfacial bonding state and configuration playing a crucial role in determining their thermal conductivity and mechanical properties. The present work aims to evaluate the bending strength and thermal conductivity of CNT-modified Ti-coated diamond/aluminum composites with multi-scale structures. The Fe catalyst was encapsulated on the surface of Ti-coated diamond particles using the solution impregnation method, and CNTs were grown in situ on the surface of Ti-coated diamond particles using the plasma-enhanced chemical vapor deposition (PECVD) method. We investigated the influence of interface structure on the thermal conductivity and mechanical properties of diamond/aluminum composites. The results show that the CNT-modified Ti-coated diamond/aluminum composite exhibits excellent bending strength, reaching up to 281 MPa, compared to uncoated diamond/aluminum composites and Ti-coated diamond/aluminum composites. The selective bonding between diamond and aluminum was improved by the interfacial reaction between Ti and diamond particles, as well as between CNT and Al. This led to the enhanced mechanical properties of Ti-coated diamond/aluminum composites while maintaining acceptable thermal conductivity. This work provides insights into the interface’s configuration design and the performance optimization of diamond/metal composites for thermal management.

A two-step brazing process was successfully employed to join MgF2 ceramic and TA15 alloy using eutectic Ag28% (in mass fraction) Cu alloy and Bi2O3B2O3ZnO (BBZ) glass as fillers, by introducing a 100 μm thick GH4169 interlayer. Multiscale characterization revealed that interdiffusion and reaction occurred at the joint interfaces. As a result, a reliable joint system consisting of TA15/TiCu/TiCu2Al/Ag(s,s) + Cu(s,s)/TiCu2Al/TiCu Ni + Ag-rich layer/GH4169/nano-oxide layer/glass/Mg3(BO3)F3+MgO + MgF2 reaction layer/MgF2 was formed. The GH4169-interlayer exhibited adaptive compatibility though its interaction with AgCu and BBZ glass fillers, effectively accommodating strong interface bonding and thermal mismatch stress between TA15 and MgF2 substrates. It shows an excellent shear strength (32 MPa, at room temperature) as well as thermal cycling stability without any cracking or spallation observed after the 20 thermal shock cycles between room temperature and 300 °C. It provides valuable insights into designing highly reliable ceramic/metal joints that demonstrate superior stability and adaptability in specific applications.

The wettability between the slag and refractory has an important relationship with the corrosion of refractory, which can elucidate the corrosion process and reveal the corrosion mechanism. In this work, the wetting process between different basicity slag and CA 6 substrate was investigated via the sessile drop method. The wetting and spread process, morphology evolution, and ion diffusion behavior were characterized and analyzed, and the interface reactions were calculated by the thermodynamic simulation software FactSage 7.1. The results show that the slag spreading process can be divided into deformation, melting, and wetting three steps. The contact angle increased with the slag basicity increased. The driving force of the higher basicity slag to penetrate CA 6 refractory is weaker, and the penetration depth is smaller, so the width of the reaction layer decreased with the slag basicity increasing, indicating the CA 6 refractory has a better corrosion resistance for high basicity slag. The results of the thermodynamic simulations show that the higher basicity slag can generate CA 2 faster, which can inhibit the slag corrosion rapidly, leading to the increment of contact angle and weaker wetting behavior for higher basicity slag. The CA 6 refractory has great potential for application in high-quality steel smelting. [ABSTRACT FROM AUTHOR]

W-Si-C composites with high relative densities and good mechanical and wear properties were successfully prepared by spark plasma sintering. The influence of SiC content on the relative density, microstructure, mechanical properties and wear characteristics was investigated. The results indicated that the reaction between SiC and W at their interface produced W2C and W5Si3. SiC also reacted with oxygen impurities at the W grain boundary to form SiO2. The purification of the grain boundaries of W was carried out by SiO2 synthesis. Reactive sintering reduces the free energy of the system and facilitates the densification process of W-Si-C composites. This results in a significant increase in the relative density of W-Si-C composites, which reaches a maximum of 98.12%, higher than the 94.32% of pure tungsten. The hardness significantly increases from 4.33 GPa to 8.40 GPa when the SiC content is 2 wt% compared to pure tungsten due to the generation of the hard ceramic phase and the increase in relative density. The wear resistance of the W-Si-C composites was significantly improved with little SiC addition. The wear rate significantly decreased from 313.27 × 10−3 mm3/N·m of pure tungsten to 5.71 × 10−3 mm3/N·m of W-0.5 wt% SiC. SEM analyses revealed that the dominant wear mechanism of pure tungsten was attributed to fatigue wear, while that of W-Si-C composites was due to abrasive wear. [ABSTRACT FROM AUTHOR]

Transparent ceramics have become a research hotspot in the preparation of fluorescent materials in recent years, because of their excellent physical and chemical properties and high transparency. Gadolinium aluminate, as a stable matrix material, is often doped with various active ions to obtain luminescence with different colors. However, it is very difficult to fabricate gadolinium aluminate transparent ceramics by a traditional method, although they are the charming solid lighting materials. Here, we developed a pressureless sintering method to prepare GdAlO3:Mn (GAP:Mn) transparent ceramic films, which were prepared by spin coating layered rare‐earth hydroxide (LRH) on amorphous alumina substrate and sintering at 1550°C for 2 h. Through the interface reaction, the Al2O3 reacted with Gd2O3 to form mesophase Gd4Al2O9 below 1550°C. However, the final products are GdAlO3 at 1550°C. The GAP:Mn4+ film exhibits a high transmittance of about 90%. Under UV excitation at 310 nm, the ceramic film outputs deep red and NIR emissions, which are both arising from the 2Eg–4A2g transition of Mn4+. Due to the electron traps arising from unequal valence substitution, the ceramic film exhibits a negative thermal quenching phenomenon. The ceramic film has a good luminescence thermal stability, because its emission intensity at 150°C maintains over 72% that at room temperature. This work may pave a new way to fabricate transparent ceramics using LRHs. [ABSTRACT FROM AUTHOR]

The stability of diamond/aluminum composite is of significant importance for its extensive application. In this paper, the interface of diamond/aluminum composite was modified by adding nanoscale W coating on diamond surface. We evaluated the corrosion rate of nanoscale W-coated and uncoated diamond/aluminum composite by a full immersion test and polarization curve test and clarified the corrosion products and corrosion mechanism of the composite. The introduction of W nanoscale coating effectively reduces the corrosion rate of the diamond/aluminum composite. After corrosion, the bending strength and thermal conductivity of the nanoscale W-coated diamond/aluminum composite are considerably higher than those of the uncoated diamond/aluminum composite. The corrosion loss of the material is mainly related to the hydrolysis of the interface product Al4C3, accompanied by the corrosion of the matrix aluminum. Our work provides guidance for improving the life of electronic devices in corrosive environments. [ABSTRACT FROM AUTHOR]

Membrane as a support for metal nanocatalysts, can greatly enhance the catalytic activity of metal nanoparticles and promote the efficient production and separation of products. In this study, a novel sandwich-structured composite membrane was designed and facilely fabricated by using palladium nanocatalysts as the core catalytic layer and two different structured PVDF layers as the outer layers. The composite membrane was used as a reaction interface as well as a separation barrier between reactants and products, efficiently realizing the catalytic oxidation of benzyl alcohol and convenient separation of the product benzaldehyde. The membrane was characterized in detailed and the effects of the membrane structure and various reaction conditions on the catalytic oxidation were systematically investigated. The results indicated that the reaction could be conveniently carried out under very mild experimental conditions, obtaining the product benzaldehyde at as high selectivity as 93.17 %. The successful implementation of the sandwich membrane for the production of chlorine-free benzaldehyde provides a new method for the interface reaction. [Display omitted] • Facile preparation of a novel sandwich-like membrane. • Membrane as interface material for reaction. • Reaction occurring between oil and water. • Novel technology for interface catalysis. [ABSTRACT FROM AUTHOR]

This study explores the growth behavior and rate-controlling processes of intermetallic compounds at Ag/Zn diffusion couple interfaces. Through experimental observations and quantitative analysis, we identify three distinct intermetallic compounds: β-AgZn, γ-Ag 5 Zn 8 , and ε-AgZn 3. We analyze the kinetics of intermetallic compound growth to elucidate the mechanisms governing thickness growth in terms of interdiffusion and interface reactions. The rate-controlling process varies with temperature; volume diffusion controls layer growth at 573–593 K, while both volume diffusion and interface reaction contribute at 623–673 K. Additionally, we evaluate the activation enthalpies of parabolic coefficients, providing insights into the temperature dependence of growth kinetics and quantitation. This comprehensive analysis clarifies the intricate mechanisms underlying intermetallic compound formation, offering valuable implications for material performance and processing optimization in various applications. [Display omitted] • We identified the formation of three intermetallic compounds (β-AgZn, γ-Ag 5 Zn 8 , ε-AgZn 3) at Ag/Zn interfaces. • The temperature dependence of the diffusion coefficient is higher compared to that of the interface reaction rate. • We evaluated activation enthalpies of parabolic coefficients for the growth, elucidating the temperature dependence. • Understanding the mechanisms governing intermetallic compound formation is crucial for material performance optimization. [ABSTRACT FROM AUTHOR]

Prebiotic chemical evolution and the emergence of life in the seafloor hydrothermal systems of Hadean Earth is among the most plausible and popular hypotheses for the origin of earthly life. In contrast, many studies pointed out that this hypothesis intrinsically harbors a critical unsolved problem called the "water paradox": Abundant water limits dehydration synthesis and instead facilitates hydrolysis of organic molecules during the early stage of chemical evolution. However, many of these criticisms have not referred to the abundant liquid/supercritical CO2 (L/SC-CO2) fluids and pools in modern hydrothermal systems, which not only create dry environments but also behave as hydrophobic solvents at and beneath the seafloor. In this paper, we theorize the generation and preservation of a L/SC-CO2 pool in modern seafloor hydrothermal systems and reinterpret the fossil hydrothermal systems preserved in early Archean seafloor basalts. The theoretical estimation of subseafloor phase separation and phase segregation of CO2-rich hydrothermal fluids suggests the presence of L/SC-CO2 fluids and pools in Hadean seafloor hydrothermal systems. Because they behave as hydrophobic organic solvents, L/SC-CO2 can potentially initiate the dehydration synthesis of organic molecules in seafloor hydrothermal systems. Moreover, at the interface between L/SC-CO2 and H2O-rich fluid (seawater or hydrothermal fluid), amphiphilic molecules might be generated and triggered into self-assembled growth. Based on the abundant occurrence and physicochemical properties of L/SC-CO2 fluids, we propose a new stepwise concept for the origin of life, whereby prebiotic chemical evolution was co-hosted and facilitated by L/SC-CO2 in Hadean water-rich seafloor hydrothermal systems. This "liquid/supercritical CO2 hypothesis" potentially overcomes the water paradox and strengthens the idea that earthly life was hatched in deep-sea hydrothermal systems. [ABSTRACT FROM AUTHOR]

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The interface reaction between directionally solidified alloy IC10 and Al2O3 ceramic mold was investigated by scanning electron microscope (SEM) and energy dispersive spectroscopy (EDS). The results show that the interface reaction between Al2O3 ceramic mold and alloy IC10 occurs, and severe sand-burning of the alloy surface is observed. Due to the high content of 1.5% (mass fraction) Hf, the activity of alloy IC10 obviously increases. The reaction zone with thickness about 5-8 μm can be divided into inner layer and outer layer. The outer layer is mainly HfO2, and the inner layer is rich in (Al,Ta,Nb) oxides, Al content is 80%. Hf and Al are the main elements induced the reactions.

W-Si-C composites with high relative densities and good mechanical and wear properties were successfully prepared by spark plasma sintering. The influence of SiC content on the relative density, microstructure, mechanical properties and wear characteristics was investigated. The results indicated that the reaction between SiC and W at their interface produced W2C and W5Si3. SiC also reacted with oxygen impurities at the W grain boundary to form SiO2. The purification of the grain boundaries of W was carried out by SiO2 synthesis. Reactive sintering reduces the free energy of the system and facilitates the densification process of W-Si-C composites. This results in a significant increase in the relative density of W-Si-C composites, which reaches a maximum of 98.12%, higher than the 94.32% of pure tungsten. The hardness significantly increases from 4.33 GPa to 8.40 GPa when the SiC content is 2 wt% compared to pure tungsten due to the generation of the hard ceramic phase and the increase in relative density. The wear resistance of the W-Si-C composites was significantly improved with little SiC addition. The wear rate significantly decreased from 313.27 × 10−3 mm3/N·m of pure tungsten to 5.71 × 10−3 mm3/N·m of W-0.5 wt% SiC. SEM analyses revealed that the dominant wear mechanism of pure tungsten was attributed to fatigue wear, while that of W-Si-C composites was due to abrasive wear.

In this research, a kind of 70-47-25% B4C/2024Al functionally graded materials (FGMs) were prepared by squeeze casting. The interfacial microstructure, precipitate characteristics and mechanical properties of B4C/2024Al FGMs were mainly studied. It was found that there was a small amount of interfacial reaction between B4C particles and Al. Mg and O elements segregated at the Al-B4C interface and MgO was formed. Under the same heat treatment conditions, the types and sizes of precipitates in different gradient layers were found to be different. Different amount of Mg segregation at the B4C-Al interface resulted in different proportion of Cu and Mg in 2024Al matrix and it makes the precipitation regions of 25 vol%, 47 vol% and 70 vol% B4C/2024Al locate in S, θ + S and θ respectively. The test results of basic properties indicated that the strength and plasticity of 70-47-25% B4C/2024Al FGMs show gradient changes. The bending stresses of 70%, 47% and 25% B4C/2024Al composites can reach 591.5 MPa, 953.4 MPa and 700.7 MPa respectively. And the elastic modulus are 240.3 GPa, 170.9 GPa and 130.7 GPa respectively. The results of this research will provide theoretical guidance for the interface structure design and heat treatment process of high strength B4C/Al composites.

Lithium-ion batteries (LIBs) are widely used in portable electronic devices, electric vehicles and large scale energy storage, due to their considerable energy density, low cost and long cycle life. However, traditional liquid batteries suffer from safety problems such as leakage, thermal runaway and even explosion. Part of the issues are caused by lithium dendrites puncturing the liquid electrolyte during cycling. In order to achieve the objective of higher safety and energy density, a rigid solid-state electrolyte (SSE) is proposed instead of liquid electrolyte (LE). Thereinto, sulfide SSEs have received of the most attention due to their high ionic conductivity. Among all the sulfide SSEs, argyrodite SSEs are considered to be one of the most promising solid-state electrolytes due to their high ionic conductivity, high thermal stability and good processablity. On the other hand, lithium metal is an ideal material for anode because of its high specific energy, low potential and large storage capacity. However, interfacial problems between argyrodite SSEs and the anode (interfacial reactions, lithium dendrites, etc.) are considered to be important factors affecting their availability. In this mini review, we summarize the behavior, properties and problems arising at the interface between argyrodite SSEs and anode. Strategies to solve interface problems and stabilize interfaces in recent years are also discussed. Finally, a brief outlook about argyrodite SSEs is presented.

The stability of diamond/aluminum composite is of significant importance for its extensive application. In this paper, the interface of diamond/aluminum composite was modified by adding nanoscale W coating on diamond surface. We evaluated the corrosion rate of nanoscale W-coated and uncoated diamond/aluminum composite by a full immersion test and polarization curve test and clarified the corrosion products and corrosion mechanism of the composite. The introduction of W nanoscale coating effectively reduces the corrosion rate of the diamond/aluminum composite. After corrosion, the bending strength and thermal conductivity of the nanoscale W-coated diamond/aluminum composite are considerably higher than those of the uncoated diamond/aluminum composite. The corrosion loss of the material is mainly related to the hydrolysis of the interface product Al4C3, accompanied by the corrosion of the matrix aluminum. Our work provides guidance for improving the life of electronic devices in corrosive environments.

To solve the limitations of clogging and erosion of the submerged entry nozzle (SEN) for the production of high-quality special steel, the chemical reactivity between different alloys and the SEN and the interface reaction between alloys and the SEN controlled by an electric current pulse (ECP) were examined in this study. Results revealed that the chemical reactivity between different alloys and the SEN is different. For example, the reactivity between rare-earth metal and the SEN was strong, while that between Al and the SEN was extremely weak. At the same time, some differences between the clogging and interface reaction by ECP control were observed. Typically, at the positive electrode of the SEN, when a stable and dense clogging layer is formed, the internal SEN was effectively protected. However, at the negative electrode of the SEN, the decarburization rate of the SEN was accelerated by ECP, probably leading to a vicious circle of accelerated clogging and erosion of the SEN. Therefore, in the future, issues of clogging, erosion, infiltration, and decarbonization between active alloys and the SEN in the casting process may be solved and regulated by using the positive electric field of ECP. Meanwhile, the gain effect of ECP also helped to promote the homogenization of molten steel. [ABSTRACT FROM AUTHOR]

The ultrasonic-assisted soldering joint of Cu/Al with different contents of copper particles added to solder powder at low temperature was studied. In this study, 15%SAC0307 solder powder with a diameter of 500 nm, different amounts copper particles with a diameter of 500 nm were mixed with zinc particles of a diameter of 45 μm to fill the Cu/Al joint, and the soldered was heated to 240 °C for ultrasonic-assisted under the environmental atmosphere. Successfully achieved micro-joining of Cu/Al under ultrasonic-assisted at low-temperature. The results have shown that, when the copper content was 0%-15%, two layers of complete and continuous CuxZny compounds were formed at the copper side interface. When the copper content was more than 15%, the IMC layer of the copper side interface was not obvious, and a large amount of CuxZny compounds were formed near the copper side. The base metals on the aluminum side formed a solid solution combination with zinc. When the addition amount of copper powder was 15%, the soldering seam was smooth and flat, the defect between balls was not obvious, and the IMC was uniformly distributed, so the average shear strength reached the maximum value of 47.37 MPa.

In this study, the reactivity between nozzle and submerged entry nozzle and alloy elements in the steel (Al and Ce) under different electric field conditions was investigated. The results show that the decarburization of the nozzle is an important factor affecting the clogging behavior and steel quality. The external electric field directly affects and changes the decarburization, clogging, and reaction behavior between the nozzle and alloy in the steel. If the chemical reaction force between alloys and the nozzle is greater than the applied electric field force in actuality, the clogging will also occur on the submerged entry nozzle. In the future, this new method of controlling and changing the interfacial electric fields can be used to solve the problem of decarburization and clogging of the submerged entry nozzle. [ABSTRACT FROM AUTHOR]

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The effect of atomic-layer-deposition (ALD)-derived Al2O3 passivation layer on the interface quality of Er2O3/Al2O3/InP laminated stacks and the improvement of electrical performance has been investigated systematically. The chemical bonding states measured by high-resolution X-ray photoelectron spectroscopy (XPS) reveal that the ALD-derived Al2O3 passivation layer can effectively inhibit the diffusion of substrate elements to optimize the interface quality. Electrical characterizations show that the optimized sample has demonstrated improved electrical properties, including the large dielectric constant of 20 and the suppressed leakage current density of 4.10 × 10−7 cm2. In addition, the leakage current conduction mechanisms are also investigated as a function of thickness of Al2O3 passivation layer. The optimized interface state density extracted from the conductance method has reduced from 1.30 × 1012 eV−1cm2 of Er2O3/InP to 7.27 × 1011 eV−1cm2 of Er2O3/Al2O3/InP by adjusting the passivation layer thickness. As a result, it can be also confirmed that the passivation treatment is beneficial to inhibit the element’s diffusion and optimize the interface quality, significantly controlling the capacitor degradation caused by the leakage current through the stacked oxide layer. [ABSTRACT FROM AUTHOR]

In this paper, thermodynamic calculation and different binary slag interface reaction experiments are used to study the reaction characteristics of different binary slag. The differences in melting process, wetting and reaction behavior were studied. The wetting angle of acidic slag is higher than that the corresponding basic slag. The variation of wetting angle between different binary slag is relatively small. The variation range is only 18 °C. In the melting and reaction process of different binary slag interfaces, the permeation and reaction of the CaO - MgO and CaO - SiO2 interfaces are relatively sufficient. However, there is no obvious chemical reaction between CaO - Al2O3 and Al2O3 - MgO, and the composition and interface separation among each component are more obvious.

ZnCl2 and SnCl2 were added to the AlF3-CsF eutectic flux, which can be used for connecting aluminum alloy sheet by self-brazing at medium temperature. The influence of the amount of ZnCl2 and SnCl2 and the size of the T-joint area on the interface microstructure and the self-brazing joint mechanical properties was investigated. The interface microstructure, chemical compositions, defects and tensile fractography of the self-brazing joints were analyzed by metallographic microscope, scanning electron microscope and energy dispersive spectroscopy. The results show that the joints are soundly bonded when both the mass fractions of ZnCl2 and SnCl2 are about 4%; the replacement reactions between Zn2+, Sn2+ of flux and Al atoms of base metal occur during brazing, then the liquid metals of Sn and Zn appear, a great degree of Zn which has high solid solution with Al spreads rapidly to the base metal; Sn is distributed along the interface forming a low melting point metal layer with Zn and Al; the brazing of joints with small area can be realized easily; there are a lot of dimples on the fracture surface and the tensile strength of the brazing joint reaches (58±5)MPa.

One of the key issues for composites is the formation mechanism and stability of the interface. Experimental technology and first-principles calculations with quasiharmonic approach considering the phonon and thermal electronic contribution are adopted to clarify the thermodynamics and thermal stress of the interface of tungsten carbide particle reinforced iron matrix (WC P /Fe) composites under finite temperature. The most favorable formation path of Fe 3 W 3 C at the interface is 3Fe+2WC + W 2 C→Fe 3 W 3 C+2C + W. For WC P /Fe and WC P /Co composites, the thermal stress of Co 3 W 3 C is smaller than Fe 3 W 3 C as the transition phase of the interface, and Fe is less suitable to be applied as the matrix of composites than Co. Our research provides significant guidance to improve the interfacial strength and stability of WC P /Fe composites. [ABSTRACT FROM AUTHOR]

The evolution of reaction phases formed in diffusion-bonded SiC/Ta–5W/SiC joints was investigated at a joining temperature of 1500–1700 °C for 10–90 min. The effects of bonding temperature and holding time on the phase evolution were found to be directly correlated with the thickness of the interfacial reaction layer when a 100-μm-thick Ta–5W interlayer was used for joining. In the case of a ~7-μm-thick reaction layer, the interfacial phase constitution consisted of a layered SiC/(Ta,W)C/(Ta,W) 5 Si 3 /(Ta,W) 2 Si/(Ta,W) x Si y /Ta–5W structure. In the reaction layer with a thickness of ~11–26 μm, the interfacial structure evolved into SiC/(Ta,W)C/(Ta,W) 5 Si 3 /(Ta,W)C/(Ta,W) x Si y /(Ta,W) 2 Si/(Ta,W) x Si y /Ta–5W, in which an additional (Ta,W)C/(Ta,W) x Si y layer was inserted between (Ta,W) 5 Si 3 and (Ta,W) x Si y owing to the precipitation of carbon from the (Ta,W) 5 Si 3 layer. When the Ta–5W interlayer was fully consumed to form a stable reaction product, namely the equilibrium state, (Ta,W) x Si y and (Ta,W) 2 Si were eventually transformed into (Ta,W) 5 Si 3 , and the final interface structure that was obtained was SiC/(Ta,W)C/(Ta,W) 5 Si 3 /(Ta,W)C/(Ta,W) 5 Si 3 /(Ta,W)C. This achievement will benefit the design, control, and characterization of SiC/metal interfaces. [ABSTRACT FROM AUTHOR]

In order to obtain high-quality superalloy castings, the wettability and interactions between superalloy melts with various Y contents and SiO 2 -based ceramic cores were investigated at 1823 K. The results indicated that the wettability and interface reactions were affected by the content of Y in the alloy. For the alloys with Y content less than 0.011 wt%, no Y-oxide was found at the interface, but HfO 2 , Al 2 O 3 and ZrO 2 phases were formed, and the wetting angle dropped slightly. However, different Y-oxides precipitated at the alloy-ceramic interface for the alloys with Y content more than 0.017 wt%, and the wetting angle dropped sharply. When the content of Y was 0.017 and 0.025 wt%, Al 2 O 3 , Y 3 Al 2 (AlO 4) 3 , HfO 2 and ZrO 2 phases were formed at the interface. When the content of Y was 0.1 wt%, YAlO 3 , Y 3 Al 5 O 12 , Y 4 Al 2 O 9 , HfO 2 and ZrO 2 phases were formed. The formation of different reaction products was mainly caused by the change of Y activity (a Y) in the alloy. The reaction between Y and SiO 2 could improve the wettability of the system apparently. [ABSTRACT FROM AUTHOR]

In order to propel the application of the developed CuNi-Xwt%Ti active filler metal in AlN brazing and get the universal reactive wetting mechanism between liquid metal and solid ceramic, the reactive wetting behavior and mechanism of AlN ceramic by CuNi-Xwt%Ti active filler metal were investigated. The results indicate that, with the increasing Ti content, surface tension for liquid CuNi-Xwt%Ti filler metal increases at low-temperature interval, but very similar at high-temperature interval, which influence the wetting behavior on AlN ceramic obviously. CuNi/AlN is the typical non-reactive wetting system, the wetting process including rapid wetting stage and stable stage. The wettability is depended on surface tension of the liquid CuNi filler metal completely. However, the wetting process of CuNi-8wt.%Ti/AlN and CuNi-16 wt%Ti/AlN reactive wetting system is composed by three stages, which are rapid wetting stage decided by surface tension, slow wetting stage caused by interfacial reaction and stable stage. For CuNi-8wt.%Ti/AlN and CuNi-16 wt%Ti/AlN reactive wetting system, although the surface tension of liquid filler metal is the only factor to influence the instant wetting angle θ 0 at rapid wetting stage, the reduced free energy caused by interfacial reaction at slow wetting stage plays the decisive role in influencing the final wettability. [ABSTRACT FROM AUTHOR]

Co has been studied extensively by many research groups as an alternative material for underbump metallization, since Co–Sn compounds show better mechanical properties than Cu–Sn compounds. Information on reactive diffusion at the solid/liquid interface is considerably important to form mechanically and electrically reliable solder joints. In the present study, the kinetics of the reactive diffusion between solid Co and liquid Sn was experimentally examined using semiinfinite Co/Sn diffusion couples prepared by an isothermal bonding technique. Isothermal annealing of the diffusion couple was conducted at temperatures in the range of 523 K to 583 K for various times up to 96 h. An intermetallic layer formed at the original Co/Sn interface in the diffusion couple during annealing. One or two intermetallic compounds among α-CoSn3, β-CoSn3, and CoSn2 were identified, depending on the annealing temperature. The total thickness of the intermetallic layer was proportional to a power function of the annealing time. The overall growth rate of the intermetallic layer did not increase with increasing annealing temperature but was dependent on the kind of compound formed at the interface. The overall growth rate at 583 K was much slower than at lower annealing temperatures, since two compounds (CoSn2 and CoSn3) were identified at the interface, while only CoSn3 formed at 523 K to 563 K. This indicates that the interdiffusion coefficient of CoSn2 is much smaller than that of CoSn3. Based on the exponent of the power function and the microstructure evolution at the moving interface, the layer growth of the compounds was controlled by volume diffusion with spheroidal growth. [ABSTRACT FROM AUTHOR]

It was speculated that ZnFe 2 O 4 was primarily responsible for activating n-butene and α-Fe 2 O 3 was used to activate O 2. The oxidative dehydrogenation of n-butene over α-Fe 2 O 3 /ZnFe 2 O 4 appeared to be the interface reaction. • ZnFe 2 O 4 was responsible for activating n-butene, α-Fe 2 O 3 was used to activate O 2. • The reaction rates were well correlated with the apparent pre-exponential factor. • Efficient contact between ZnFe 2 O 4 and α-Fe 2 O 3 may lead to improving activity. • ODH of n-butene over α-Fe 2 O 3 /ZnFe 2 O 4 appeared to be the interface reaction. Iron-based catalysts were one of the most effective catalysts in the oxidative dehydrogenation of n-butene, however, the roles of spinel and α-Fe 2 O 3 in the biphasic catalyst have remained controversial. Herein, we found that biphasic catalyst exhibited much superior catalytic performance compared to each individual component. According to the temperature programmed desorption, XPS and kinetics studies results, it was speculated that ZnFe 2 O 4 was primarily responsible for activating n-butene and α-Fe 2 O 3 was used to activate O 2. Moreover, the key factor for the catalytic activity of the biphasic catalyst were investigated and kinetic studies showed that reaction rates were well correlated with the apparent pre-exponential factor. Therefore, the efficient contact between ZnFe 2 O 4 and α-Fe 2 O 3 may lead to the improvement of the activity. In addition, the reaction mechanism over α-Fe 2 O 3 /ZnFe 2 O 4 was proposed to be the interface reaction based on the catalytic evaluation results of substituting ZnFe 2 O 4 by the redox-inactive ZnAl 2 O 4. [ABSTRACT FROM AUTHOR]

In this study, we focused on unraveling the intricate world of intermetallic compound formation at the interface of solid Fe and liquid Al–Mg–Si alloy. Our primary aim was to shed light on the phenomenon of Fe degradation in molten Al alloys. Our investigation led us to discover two distinct intermetallic phases, namely Fe 2 Al 5 and Fe 4 Al 13 , each exhibiting unique growth dynamics influenced by the interplay of volume diffusion and interface reactions. Moreover, delving deeper into the mechanics of these processes, we meticulously analyzed the rate-controlling mechanisms governing layer growth, exploring both volume diffusion and interface reactions. Furthermore, we quantified the activation enthalpy associated with these phenomena, enriching our understanding of the energy barriers involved in atom or molecule diffusion across solid-liquid interfaces. The implications of our findings extend far beyond the confines of the laboratory, holding significant promise for real-world applications. These insights into Fe degradation prevention and the enhancement of Al alloy performance when in contact with Fe materials offer exciting prospects for materials design and process optimization across diverse engineering and industrial domains. [Display omitted] • Fe 2 Al 5 has an irregular saw-tooth morphology consisting of polycrystalline grains. • A thin and continuous Fe 4 Al 13 phase layer acted as a diffusion barrier. • The rate-controlling process and activation enthalpy of IMC growth was evaluated. • The study quantitatively investigated the morphology evolution of Fe 2 Al 5. • The growth of IMC was controlled by both interdiffusion and interface reaction. [ABSTRACT FROM AUTHOR]

Aluminum foam sandwiches (AFS) with AlSi10 foam cores and AISI 316L steel skins are manufactured by an in-situ bonding process. The precursor of the core foam was made with the powder compacted method. The precursor and skins, coupled together, were then heated up to the melting point of the Al alloy. The gas released by the blowing agent formed hydrogen bubbles in the melt. producing the foam. Such a porous structure was kept frozen at room temperature via cooling in cold water. To optimize the process conditions, some foaming experiments have been conducted with different holding times and temperatures. Such manufactured AFS were cut, chemically etched and studied with an optical microscope associated with image analysis software to get information about pores morphology in terms of circularity and equivalent diameter. The interface AlSi10-AISI316L has been characterized by SEM and EDX to investigate the bonding conditions between cores and skins. Finally, the AFS have been polished and etched to analyze the microstructure. Quasi-static compressive tests have been performed on the AFS. Obtained results showed that the interface formed during the foaming can be characterized by the inter-diffusion of alloying elements, as confirmed by the good quality of metallurgical joints.

In this paper, the effect of Y content on interface reaction and wettability between a nickel-base single crystal supperalloy melt and ceramic mould were studied by means of sessile drop tests. The microstructural characterization of the alloy-ceramic interface and the elemental compositions of reaction products were performed by scanning electron microscope (SEM) and electron probe micro-analyzer (EPMA), the phases of reaction products were identified by X-ray diffraction (XRD), and the surface analysis of reaction products was carried out by X-ray photoelectron spectroscopy (XPS). The results showed that Al and Hf in the alloy reacted with SiO 2 in the ceramic mould when Y content was lower than 0.011 wt%, and the reaction products were Al 2 O 3 and HfO 2 , with little change in the wetting angle. However, when Y content was higher than 0.017 wt%, Y and Al in the alloy reacted with SiO 2 in the ceramic mould, and the wetting angle decreased significantly. 0.017 wt% was the critical concentration of Y content that would cause interface reactions. The reaction products of 0.017 and 0.025 wt% Y alloys were Y 3 Al 2 (AlO 4) 3 , the reaction products of 0.1 wt% Y alloy were Y 3 Al 5 O 12 and Y 4 Al 2 O 9 , and the reaction products of 0.5 and 1.0 wt% Y alloys were double reaction layer composed of Y 2 O 3 and Y 3 Al 5 O 12. Si generated by the interface reactions could react with O 2 in the atmosphere to form SiO x during the cooling of the alloy-ceramic couples. • Y-containing interface reactions can obviously increase the wettability. • Al 2 O 3 and HfO 2 are formed at the interface when Y content is less than 0.011 wt%. • Different yttrium aluminate oxides are formed when Y content exceeds 0.017 wt%. • Si generated reacts with O 2 in the atmosphere to form SiO x during the cooling. [ABSTRACT FROM AUTHOR]

Abstract Polymer composite materials are used increasingly in material and engineering science. They provide outstanding mechanical and optical properties. The linkage between the polymer materials is crucial for achieving the desired properties. Understanding the linkage and structure of the polymer-polymer interface layer is a key for utilization polymer composite materials as well as for their fabrication. When analyzing the thin polymer-polymer interface it is important to achieve clear identification of molecular linker structures. One reliable analytical technique allowing this is surface enhanced Raman scattering (SERS) spectroscopy. This study aims at the in-situ evaluation of SERS spectra recorded from the Polycarbonate (PC) –Octadecylamine (ODA) interface to identify the formation of urethane bonds. The detailed analysis of SERS spectra taken before and after the chemical linkage reaction reveals the formation of urethane structures, indicating a chemical bond between PC and ODA. The spectral pattern of urethane groups was identified and evaluated by a reference Raman spectrum. Graphical abstract Image 1 Highlights • Nondestructive in-situ characterization of polymer interphase by SERS. • Silver nanoparticles located at the polymer interface. • Evaluation of molecular interphase structure between Polycarbonate-Octadecylamine. • Formation of an initial urethane linkage. [ABSTRACT FROM AUTHOR]

Abstract Synthetic diamond has excellent mechanical, thermal, and electrical properties, which makes it an ideal material in a wide range applications from abrasive grinding tools to modern electronic devices. Hence, understanding the wettability of metals on the synthetic diamond is of great importance for the development of diamond-related materials and devices. In this study, the wettability and spreading kinetics of binary Sn Cr alloy on chemical vapour deposed (CVD) polycrystalline diamond compacts were investigated using a sessile drop method. In situ observation of contact angle at elevating temperatures indicated trace addition of Cr dramatically improved the wettability of Sn on CVD diamond, and the Sn Cr alloy started to wet CVD diamond at approximately 750 °C. Isothermal spreading kinetic analysis revealed that the spreading of Sn Cr alloy on CVD diamond was controlled by the kinetics of chemical reaction at advancing triple line. Microstructure characterization indicated that the formation of nano-sized scallop-like Cr 7 C 3 grains was responsible for the improved wettability of Sn Cr alloy on CVD diamond substrate. The wetting temperature was found to play a determinant role in the interfacial carbide formation, and hence the reactive wetting of Sn Cr alloy on CVD diamond at temperatures from 700 to 900 °C. Graphical abstract Unlabelled Image Highlights • Small amount of Cr initiates the reactive wetting of Sn on CVD diamond at 750 °C. • Wettability and spreading kinetics of Sn Cr alloys are very sensitive to temperature. • Spreading of Sn Cr alloy is controlled by the chemical reaction kinetics during isothermal wetting. • Formation of nano-sized Cr 7 C 3 carbide improves the wettability of Sn Cr alloy on CVD diamond. [ABSTRACT FROM AUTHOR]

In this paper, thermodynamic calculation and different binary slag interface reaction experiments are used to study the reaction characteristics of different binary slag. The differences in melting process, wetting and reaction behavior were studied. The wetting angle of acidic slag is higher than that the corresponding basic slag. The variation of wetting angle between different binary slag is relatively small. The variation range is only 18 °C. In the melting and reaction process of different binary slag interfaces, the permeation and reaction of the CaO - MgO and CaO - SiO2 interfaces are relatively sufficient. However, there is no obvious chemical reaction between CaO - Al2O3 and Al2O3 - MgO, and the composition and interface separation among each component are more obvious. [ABSTRACT FROM AUTHOR]

Facile and environment-friendly preparation of chloride-free benzaldehyde is still a great challenge in industry. Herein, a novel bilayer composite membrane with a top semi-interpenetrating polymer network layer and a lower polyvinylidene fluoride/poly (methacrylic acid) @Pd catalytic layer was prepared for the green preparation of chloride-free benzaldehyde. Results indicated that when the composite membrane was placed between the interface of H 2 O 2 /water solution and benzyl alcohol/toluene solution, it could efficiently and conveniently catalyze the oxidation of benzyl alcohol by hydrogen peroxide into chloride-free benzaldehyde. Furthermore, the oil phase and water phase were always separated by the bilayer membrane during the whole process and thus the reaction was operated conveniently. The good result was attributed to the unique structure of the bilayer membrane and the interface reaction technique. Undoubtedly, coupling the bilayer membrane with the interface reaction technique is a new and effective strategy for the green preparation of chloride-free benzaldehyde. [Display omitted] • A bilayer membrane has two layers with different hydrophilic properties. • Membrane is coupled with interface reaction for benzyl alcohol oxidation. • High conversion and selectivity are simultaneously obtained. • Facile and environmentally friendly technique is used for benzaldehyde preparation. [ABSTRACT FROM AUTHOR]