There are numerous applications of nanoporous materials, including gas storage, separation, and purification. In recent years, the number of available nanoporous materials has increased substantially, with new material classes, such as metal-organic frameworks and microporous organic polymers, joining the traditional adsorbents, which include activated carbons, porous silicas, and zeolites. The determination of the gas adsorption properties of these materials is critical to both the development of new materials for targeted applications and the assessment of the suitability of a material for a particular technology. In this article, we provide an overview of nanoporous materials and their gas adsorption properties, existing and future applications for new materials, adsorption measurement methods, and the experimental challenges involved in the determination of gas adsorption both at elevated pressures and from multicomponent mixtures.

Bioinspired surfaces with special wettability have rapidly emerged at the forefront of materials research. What is behind biological surfaces with special wettability, and how can we realize special wettability properties for artificial materials? This article describes how the interplay between unique multiscale (micro- and nanoscale) structures of biological surfaces and intrinsic material properties plays a crucial role in achieving the desired wettability and functionalities. Taking inspiration from natural surfaces, researchers have designed and created novel interfacial materials with versatile special wettability, such as superantiwetting surfaces (superhydrophobic and superoleophobic), smart switchable surfaces, and water collecting surfaces.

Carbon nanocoils (CNCs) with different diameters have been synthesized on different substrates by thermal chemical vapor deposition using Fe films as catalysts prepared by ion sputtering. It is found that CNCs with diameters greater than 100 nm are obtained as the main products in large quantities on Fe film coated indium tin oxide substrates. However, on Fe film coated SiO2 substrates, multiwall CNCs (MWCNCs) along with carbon nanotubes (CNTs) are grown, and the yield of MWCNCs is decreased rapidly with a lower Fe film thickness. The as-grown MWCNCs with observed coil diameters less than 100 nm and filament diameters less than 30 nm are much thinner than the conventional CNCs. Plate-like catalyst particles with sizes much larger than the filament diameter of the MWCNCs are observed at the roots of these MWCNCs, indicating a base growth mechanism. Furthermore, it is also observed that large particles with irregular shapes lead to the growth of helical MWCNCs, while large particles with steady circular shapes tend to grow as straight CNTs. Based on the experimental results, a growth model for MWCNCs is proposed.

Condensation is a phase change phenomenon often encountered in nature, as well as used in industry for applications including power generation, thermal management, desalination, and environmental control. For the past eight decades, researchers have focused on creating surfaces allowing condensed droplets to be easily removed by gravity for enhanced heat transfer performance. Recent advancements in nanofabrication have enabled increased control of surface structuring for the development of superhydrophobic surfaces with even higher droplet mobility and, in some cases, coalescence-induced droplet jumping. Here, we provide a review of new insights gained to tailor superhydrophobic surfaces for enhanced condensation heat transfer considering the role of surface structure, nucleation density, droplet morphology, and droplet dynamics. Furthermore, we identify challenges and new opportunities to advance these surfaces for broad implementation in thermofluidic systems.

Surface wettability has emerged as a powerful tool to influence phase change phenomena such as ice formation and steam condensation. Ice mitigation using passive coatings offers tremendous promise; however, there remain several fundamental, durability- and manufacturing-related challenges that need to be addressed to harness the benefits of these coatings. Challenges limiting industrial utilization of such coatings can be classified into three categories: fundamental (frost buildup, non-zero ice adhesion, bulk ice nucleation, variable icing conditions), durability-related (harsh environment resistance, liquid impact resistance, erosion, fatigue), and manufacturing-related (scalability, coating economics). The role of passive surfaces in enhancing condensation heat transfer is a potential game changer in power plant efficiency enhancement; however, the benefits of such coatings will only be realized when durability and manufacturing challenges have been fully addressed.

Microstructures and mechanical properties of the Mg–4Y–2.5Nd–0.6Zr (wt%) alloy in the as-cast, as-rolled, and rolled-T5 conditions have been investigated. Results showed that the as-cast sample mainly consisted of the α-Mg matrix, network-like Mg41Nd5 phase, and cuboid-shaped Mg24Y5 particles. For the as-rolled sample, the thermally stable Mg24Y5 particles located at both grain boundaries and matrix, and the average grain size was greatly refined to about 15 μm. Yield strength, ultimate tensile strength, and elongation of as-rolled samples were 290 MPa, 235 MPa, and 10%, respectively. They were enhanced by 48.7%, 56.7%, and 38.9% correspondingly compared with those of the as-cast sample. After isothermal aging at 250 °C for 4 h, the optimal mechanical properties can be obtained. Besides, the tensile strengths of as-rolled and rolled-T5 samples decreased gradually with a gradual increase of ductility from room temperature to 300 °C. Quasicleavage and cleavage fracture were the fracture patterns of as-rolled and rolled-T5 samples, respectively, at room temperature. For samples under the two conditions, fracture mode similarly changed with the increase of test temperatures, and ductile fracture can be observed at higher temperature.

Reusable thermal protection systems of reentry vehicles are adopted for temperatures ranging between 1000 and 2000 °C, when gas velocity and density are relatively low; they exploit the low thermal conductivity of their constituent materials. This paper presents a new class of light structural thermal protection systems comprised of a load bearing structure made of a macroporous reticulated SiSiC, filled with compacted short alumina/mullite fibers. Their manufacturing process is very simple and does not require special devices or ambient conditions. The produced hetoroporous heterogeneous ceramics showed high radiations shielding capabilities up to 2000 °C in vacuum. Even after repeated exposures at higher temperatures, a significant degradation of the SiSiC scaffold was not observed.

Surfaces that display liquid contact angles greater than 150° along with low contact angle hysteresis for liquids with both high and low surface tension values are known as superomniphobic surfaces. Such surfaces are of interest for a diverse array of applications, including self-cleaning surfaces, nonfouling surfaces, stain-free clothing, spill-resistant protective wear, drag reduction, and fingerprint-resistant surfaces. Recently, significant advances have been made in understanding the criteria required to design superomniphobic surfaces. In this article, we discuss the roles of surface energy, roughness, re-entrant texture, and hierarchical structure in fabricating superomniphobic surfaces. We also provide a review of different superomniphobic surfaces reported recently in the literature and emphasize the need for mechanical, chemical, and radiation durability of superomniphobic surfaces for practical applications. Finally, we conclude with a discussion of the unresolved challenges in developing durable superomniphobic surfaces that define the scope for further improvements in the field.