Ternary alloys have been developed for a wide range of applications and surface segregation of ternary alloys has a decisive impact on their performance. Different from binary alloys, in which surface energy is usually the dominant factor, the interaction between solute elements has a noticeable effect on the surface segregation behavior of ternary alloys. As a practical example, Pd-based ternary alloys have been proposed as promising candidates for hydrogen separation membranes due to their excellent permeability and selectivity. In the present work, surface segregation of Pd-Cu-Ag and Pd-Cu-Mo ternary alloys in both vacuum and hydrogen atmosphere is investigated. X-ray photoelectron spectroscopy and low energy ion scattering spectroscopy analyses reveal that the segregation trend of the outermost atomic layer is not always the same as that of the near-surface region. A thermodynamic model is developed to describe the surface segregation of ternary alloys. The results of the model are in good qualitative agreement with experimental results. Furthermore, calculations for other ternary alloy systems confirm that the model provides a simple but universal method for surface segregation in ternary alloys. The results can also be considered as basic guidelines to design novel ternary alloys for various applications.

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Pd–Cu alloys have been investigated as promising candidates for hydrogen separation membranes. Surface segregation influences the long-term performance of these membranes since their catalytic effect is mainly controlled by the surface composition. In the present research, surface segregation of Pd-40 at.% Cu alloy in vacuum and various gas atmospheres (H₂, CO and CO₂) was investigated with both XPS and LEISS probing different depths below the surface. Adsorption of H₂ and CO on the surface has a significant impact and the surface segregation trend can be reversed as compared to segregation in vacuum, however, CO₂ has almost no influence on the segregation behaviour. A thermodynamic model is also presented to explain these phenomena and to understand surface segregation behaviour of binary alloys in various gas atmospheres. The results can be considered as basic guidelines to design novel alloys for hydrogen separation membranes and predict their long-term performance under actual working conditions.

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Reported here is a 2D, interfacial microcompartmentalization strategy governed by 3D phase separation. In aqueous polyethylene glycol (PEG) solutions doped with biotinylated polymers, the polymers spontaneously accumulate in the interfacial layer between the oil-surfactant-water interface and the adjacent polymer phase. In aqueous two-phase systems, these polymers first accumulated in the interfacial layer separating two polymer solutions and then selectively migrated to the oil-PEG interfacial layer. By using polymers with varying photopolymerizable groups and crosslinking rates, kinetic control and capture of spatial organisation in a variety of compartmentalized macroscopic structures, without the need of creating barrier layers, was achieved. This selective interfacial accumulation provides an extension of 3D phase separation towards synthetic compartmentalization, and is also relevant for understanding intracellular organisation.

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Hydrogel microparticles are important in materials engineering, but their applications remain limited owing to the difficulties associated with their manipulation. Herein, we report the self-orientation of crescent-shaped hydrogel microparticles and elucidate its mechanism. Additionally, the microparticles were used, for the first time, as micro-buckets to carry living cells. In aqueous solution, the microparticles spontaneously rotated to a preferred orientation with the cavity facing up. We developed a geometric model that explains the self-orienting behavior of crescent-shaped particles by minimizing the potential energy of this specific morphology. Finally, we selectively modified the particles’ cavities with RGD peptide and exploited their preferred orientation to load them with living cells. Cells could adhere, proliferate, and be transported and released in vitro. These micro-buckets hold a great potential for applications in smart materials, cell therapy, and biological engineering.

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Rare-earth zirconates (RE₂Zr₂O₇, RE = rare earth elements) are considered as promising thermal barrier coating (TBCs) materials. However, their thermal expansion coefficient (TEC) is relatively low comparing with that of either the state-of-the-art TBCs material Yttria-stabilized Zirconia (YSZ), or the metallic bond-coat. In present research, Cerium was introduced as the substitution of Zirconium to improve the TEC of rare-earth zirconates. A series of Yb₂(Zr_1−xCe_x)₂O₇ solid solutions were synthesized and investigated. Experimental results revealed that their TEC is remarkably increased with the Cerium substitution content. Meanwhile, their thermal conductivity shows no obvious increase compared with that of Yb₂Zr₂O₇due to the phonon scattering effect.

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Pyrochlore-related compound Sm₂FeTaO₇ was synthesized and investigated. It is shown that the thermal conductivity values are approximately half of the Yttria-Stabilized Zirconia (YSZ) over the temperature range of 25–1000 °C. Especially, thermal conductivity at high temperature is close to that of minimum thermal conductivity, as predicted by theoretical investigation, signifying better heat insulation capabilities. Considering lower Young modulus, improved fracture toughness, and better high-temperature phase stability, Sm₂FeTaO₇ compound can be a promising material for thermal insulating applications, such as thermal barrier coatings.

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Water-purifying materials are of vital importance for providing sanitary water, especially in epidemic and disaster areas and for wilderness survival. Here, we report a novel inorganic composite with a fast, reusable, and pleiotropic water purification ability. The composite of heterogeneous Ni-La2O3 nanofibers was developed using an easy, low-cost, and large-scale production process, i.e., an electrospinning technique. Because of the unique heterostructure formed by introducing nickel nanoparticles into the La2O3 host, the nanocomposite fibers can rapidly remove various detrimental micropollutants with absorption rate constants hundreds of times greater than those of inorganic materials and activated carbons. In addition, the nanocomposite can be recycled by a soft washing procedure at ambient temperature and demonstrates a much more stable performance than the state-of-the-art activated carbon materials. Furthermore, the nanofibers have an excellent germicidal effect against the high-risk human pathogen Escherichia coli. Our work introduces a promising inorganic absorbent suitable for purifying life-sustaining water supplies in emergency situations and alleviating worldwide water shortages.@en

Surface segregation of a series of forty Palladium-based binary alloys has been investigated using a thermodynamic model based on an atom exchange approach. Their surface segregation behaviour, both in vacuum and in gas environments, were comprehensively estimated. The calculated results are in good agreement with the available experimental and computational data reported in literatures. Effects of mixing enthalpy, temperature, crystal orientation on the surface, elastic strain energy, adsorption and absorption of gases like H₂, O₂, CO have been discussed in detail. These results can be considered as basic guidelines to design novel Pd alloys for hydrogen separation membranes, sensors or catalysts. The model itself also offers a convenient and accurate routine to predict the surface segregation of other than Pd-based binary alloys in different gas atmospheres.

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