Superelastic carbon aerogels have been widely explored by graphitic carbons and soft carbons. These soft aerogels usually have delicate microstructures with good fatigue resistance but ultralow ...strength. Hard carbon aerogels show great advantages in mechanical strength and structural stability due to the sp3‐C‐induced turbostratic “house‐of‐cards” structure. However, it is still a challenge to fabricate superelastic hard carbon‐based aerogels. Through rational nanofibrous structural design, the traditional rigid phenolic resin can be converted into superelastic hard carbon aerogels. The hard carbon nanofibers and abundant welded junctions endow the hard carbon aerogels with robust and stable mechanical performance, including superelasticity, high strength, extremely fast recovery speed (860 mm s−1), low energy‐loss coefficient (<0.16), long cycle lifespan, and heat/cold‐endurance. These emerging hard carbon nanofiber aerogels hold a great promise in the application of piezoresistive stress sensors with high stability and wide detection range (50 kPa), as well as stretchable or bendable conductors.
A family of hard carbon aerogels with nanofibrous structure templated by various nanofibers is fabricated, displaying robust and stable mechanical performances, including high strength, extremely fast recovery speed (860 mm s−1), and ultralow energy loss coefficient (<0.16). After being compressed for 104 cycles (50% strain), they show only ≈2% plastic deformation and retain ≈93% stress.
As an abundant natural resource, wood has gained great attention for thousands of years, spanning from the primitive construction materials to the modern high‐added‐value engineering materials. The ...unique delicate microstructures and the wonderful properties (e.g., low‐density, high strength and stiffness, good toughness, and environmental sustainability) have made wood a natural source of inspiration that guides researchers to invent various wood‐inspired materials. Herein, as an emerging material system, bioinspired artificial wood, with similar cellular structures and comparable mechanical properties, is discussed in the view of the design concept, fabrication strategy, properties, and possible applications. The present challenges and further research opportunities are also presented for artificial woods to thrive. To achieve the final eco‐friendly artificial wood, more endeavors should be made in biomaterials and biodegradable or recyclable engineering of polymers to gain high mechanical properties and environmental sustainability simultaneously.
Artificial woods have emerged as a novel kind of wood‐inspired engineering material with almost exactly the same channel microstructures and similar wall components. The performances of artificial woods depend on both the oriented channel and wall designs. The rational combination of other engineering polymers and channel‐making techniques hold promise to develop more useful artificial woods.
The anode oxygen evolution reaction (OER) is known to largely limit the efficiency of electrolyzers owing to its sluggish kinetics. While crystalline metal oxides are promising as OER catalysts, ...their amorphous phases also show high activities. Efforts to produce amorphous metal oxides have progressed slowly, and how an amorphous structure benefits the catalytic performances remains elusive. Now the first scalable synthesis of amorphous NiFeMo oxide (up to 515 g in one batch) is presented with homogeneous elemental distribution via a facile supersaturated co‐precipitation method. In contrast to its crystalline counterpart, amorphous NiFeMo oxide undergoes a faster surface self‐reconstruction process during OER, forming a metal oxy(hydroxide) active layer with rich oxygen vacancies, leading to superior OER activity (280 mV overpotential at 10 mA cm−2 in 0.1 m KOH). This opens up the potential of fast, facile, and scale‐up production of amorphous metal oxides for high‐performance OER catalysts.
Amorphous NiFeMo oxide (up to 515 g one batch) with homogeneous elemental distribution was synthesized through a facile supersaturated co‐precipitation method. The amorphous NiFeMo oxide undergoes rapid surface self‐reconstruction during OER that forms a metal oxy(hydroxide) active layer with oxygen vacancies, enabling efficient OER catalysis.
SiOx is proposed as one of the most promising anodes for Li‐ion batteries (LIBs) for its advantageous capacity and stable Li uptake/release electrochemistry, yet its practical application is still a ...big challenge. Here encapsulation of SiOx nanoparticles into conductive graphene bubble film via a facile and scalable self‐assembly in solution is shown. The SiOx nanoparticles are closely wrapped in multilayered graphene to reconstruct a flake‐graphite‐like macrostructure, which promises uniform and agglomeration‐free distribution of SiOx in the carbon while ensures a high mechanical strength and a high tap density of the composite. The composites present unprecedented cycling stability and excellent rate capabilities upon Li storage, rendering an opportunity for its anode use in the next‐generation high‐energy LIBs.
SiOx nanoparticles are closely wrapped in multilayered graphene to reconstruct a macrostructure resembling flake graphite, which promises agglomeration‐free distribution of SiOx in the bulk while ensuring a high mechanical strength and a high tap density of the bubble film. By taking the advantages of the graphene network, the composites present unprecedented cycling stability and excellent rate capabilities upon Li storage.
Soft woods have attracted enormous interest due to their anisotropic cellular microstructure and unique flexibility. The conventional wood-like materials are usually subject to the conflict between ...the superflexibility and robustness. Inspired by the synergistic compositions of soft suberin and rigid lignin of cork wood which has good flexibility and mechanical robustness, an artificial soft wood is reported by freeze-casting the soft-in-rigid (rubber-in-resin) emulsions, where the carboxy nitrile rubber confers softness and rigid melamine resin provides stiffness. The subsequent thermal curing induces micro-scale phase inversion and leads to a continuous soft phase strengthened by interspersed rigid ingredients. The unique configuration ensures crack resistance, structural robustness and superb flexibility, including wide-angle bending, twisting, and stretching abilities in various directions, as well as excellent fatigue resistance and high strength, overwhelming the natural soft wood and most wood-inspired materials. This superflexible artificial soft wood represents a promising substrate for bending-insensitive stress sensors.
Cellulose aerogels are plagued by intermolecular hydrogen bond‐induced structural plasticity, otherwise rely on chemicals modification to extend service life. Here, we demonstrate a ...petrochemical‐free strategy to fabricate superelastic cellulose aerogels by designing hierarchical structures at multi scales. Oriented channels consolidate the whole architecture. Porous walls of dehydrated cellulose derived from thermal etching not only exhibit decreased rigidity and stickiness, but also guide the microscopic deformation and mitigate localized large strain, preventing structural collapse. The aerogels show exceptional stability, including temperature‐invariant elasticity, fatigue resistance (∼5 % plastic deformation after 105 cycles), high angular recovery speed (1475.4° s−1), outperforming most cellulose‐based aerogels. This benign strategy retains the biosafety of biomass and provides an alternative filter material for health‐related applications, such as face masks and air purification.
A new type of cellulose aerogels with anisotropic and hierarchical porous architecture are developed via a petrochemical‐free method. The aerogels display temperature‐invariant elasticity (∼5 % plastic deformation after 105 compressive cycles at 50 % strain), large‐strain recoverability (folding and twisting), angular recovery speed high up to 1475.4° s−1, and exceptional fatigue resistance.
Polymer‐derived carbon aerogels can be obtained by direct polymerization of monomers under hypersaline conditions using inorganic salts. This allows for significantly increased mechanical robustness ...and avoiding special drying processes. This concept was realized by conducting the polymerization of phenol–formaldehyde (PF) in the presence of ZnCl2 salt. Afterwards, the simultaneous carbonization and foaming process conveniently converts the PF monolith into a foam‐like carbon aerogel. ZnCl2 plays a key role, serving as dehydration agent, foaming agent, and porogen. The carbon aerogels thus obtained are of very low density (25 mg cm−3), high specific surface area (1340 m2 g−1), and have a large micro‐ and mesopore volume (0.75 cm3 g−1). The carbon aerogels show very promising potential in the separation/extraction of organic pollutants and for energy storage.
Rather salty: Carbon aerogels were obtained upon conducting the polymerization of phenol–formaldehyde (PF) resin under hypersaline conditions, for example, by using ZnCl2. The simultaneous carbonization and foaming process conveniently converts the PF monoliths into foam‐like carbon aerogels.
Hard carbons attract myriad interest as anode materials for high-energy rechargeable batteries due to their low costs and high theoretical capacities; practically, they deliver unsatisfactory ...performance due to their intrinsically disordered microarchitecture. Here we report a facile ion-catalyzed synthesis of a phenol–formaldehyde resin-based hard-carbon aerogel that takes advantage of the chelation effect of phenol and Fe3+, which consists of a three-dimensionally interconnected carbon network embedded with hydrogen-rich, ordered microstructures of expanded nanographites and carbon micropores. The chelation effect ensures the homodispersion of Fe in the polymer segments of the precursor, so that an effective catalytic conversion from sp3 to sp2 carbon occurs, enabling free rearrangement of graphene sheets into expanded nanographite and carbon micropores. The structural merits of the carbon offer chances to achieve lithium/sodium storage performance far beyond that possible with the conventional carbon anode materials, including graphite and mesocarbon microbeads, along with fast kinetics and long cycle life. In this way, our hard carbon proves its feasibility to serve as an advanced anode material for high-energy rechargeable Li/Na batteries.
Background
Primary gastric linitis plastica (GLP) is a distinct phenotype of gastric cancer with poor survival. Comprehensive molecular profiles and putative therapeutic targets of GLP remain ...undetermined.
Methods
We subjected 10 tumor-normal tissue pairs to whole exome sequencing (WES) and whole transcriptome sequencing (WTS). 10 tumor samples were all GLP which involves 100% of the gastric wall macroscopically. TCGA data were compared to generate the top mutated genes and the overexpressed genes in GLP.
Results
Our results reveal that GLP has distinctive genomic and transcriptomic features, dysfunction in the Hippo pathway is likely to be a key step during GLP development. 6 genes were identified as significantly highly mutated genes in GLP, including AOX1, ANKRD36C, CPXM1, PTPN14, RPAP1, and DCDC1). MUC6, as a previously identified gastric cancer driver gene, has a high mutation rate (20%) in GLP. 20% of patients in our GLP cohort had CDH1 mutations, while none had RHOA mutations. GLP exhibits high immunodeficiency and low AMPK pathway activity. Our WTS results showed that 3 PI3K-AKT pathway-related genes (PIK3R2, AKT3, and IGF1) were significantly up-regulated in GLP. Two genes were identified using immunohistochemistry (IHC), IGF2BP3 and MUC16, which specifically expressed in diffuse-type-related gastric cancer cell lines, and its knockdown inhibits PI3K-AKT pathway activity.
Conclusions
We provide the first integrative genomic and transcriptomic profiles of GLP, which may facilitate its diagnosis, prognosis, and treatment.
Two‐dimensional (2D) materials are promising successors for silicon transistor channels in ultimately scaled devices, necessitating significant research efforts to study their behavior at nanoscopic ...length scales. Unfortunately, current research has limited itself to direct patterning approaches, which limit the achievable resolution to the diffraction limit and introduce unwanted defects into the 2D material. The potential of multi‐patterning to fabricate 2D materials features with unprecedented precision and low complexity at large scale is demonstrated here. By combining lithographic patterning of a mandrel and bottom‐up self‐expansion, this approach enables pattern resolution one order of magnitude below the lithographical resolution. In‐depth characterization of the self‐expansion double patterning (SEDP) process reveals the ability to manipulate the critical dimension with nanometer precision through a self‐limiting and temperature‐controlled oxidation process. These results indicate that the SEDP process can regain the quality and morphology of the 2D material, as shown by high‐resolution microscopy and optical spectroscopy. This approach is shown to open up new avenues for research into high‐performance, ultra‐scaled 2D materials devices for future electronics.
A versatile multi‐patterning approach is introduced as a tool to support researchers in studying 2D materials integration into nanoscaled electronic devices. The critical dimension of the self‐aligned process does not depend on the diffraction limit but on a bottom‐up expansion step. This method supports scalable 2D materials‐based electronics at high quality for future studies in the field.
