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Summary The further development of flexible electronics inevitably requires conductive materials to have numerous foldable properties; however, that has not been realized. Here, inspired by silkworm cocooning processes, we prepare a super-foldable conductive carbon material with layered nanofiber network structures through an improved electrospinning/carbonization technique. It can remarkably bear 1,000,000 times repeated true-folding without structural damage and conductivity fluctuations. The root of such performance breakthrough is revealed through real-time SEM folding observation and mechanical simulations. Its structures featuring appropriate pores, non-crosslinked junctions, slidable nanofibers, separable layers, and a compressible network can act synergistically to generate a e-like folding construction at crease under true-folding, which can completely disperse stress via bulged layers, dispersed arcs, and slidable grooves in e. Consequently, each nanofiber avoids directly facing with 180° folding when the whole material is true-folded. This work embodies structure innovation, performance breakthrough, and mechanism reveal, which has great scientific significance and application prospects.

Poria cocos is a traditional Chinese medicine (TCM) that can clear dampness, promote diuresis, and strengthen the spleen and stomach. Poria cocos has been detected in many TCM compounds that are used for COVID-19 intervention. However, the active ingredients and mechanisms associated with the effect of Poria cocos on COVID-19 remain unclear. In this paper, the active ingredients of Poria cocos, along with their potential targets related to COVID-19, were screened using TCMSP, GeneCards, and other databases, by means of network pharmacology. We then investigated the active components, potential targets, and interactions, that are associated with COVID-19 intervention. The primary protease of COVID-19, Mpro, is currently a key target in the design of potential inhibitors. Molecular docking techniques and molecular dynamics simulations demonstrated that the active components of Poria cocos could bind stably to the active site of Mpro with high levels of binding activity. Pachymic acid is based on a triterpene structure and was identified as the main component of Poria cocos; its triterpene active component has low binding energy with Mpro. The pachymic acid of Mpro activity was further characterized and the IC50 was determined to be 18.607 μmol L−1. Our results indicate that pachymic acid exhibits a certain inhibitory effect on the Mpro protease.

Boron nitride (BN) has been widely studied as an efficient catalyst for oxidative propane dehydrogenation (OPDH). Oxygen-containing boron species (e.g., BO·, B(

Recent progress in flexible electronics has attracted tremendous attention. However, it is still difficult to prepare superfoldable conductive materials with good biocompatibility, high sensing sensitivities, and large specific surface areas. It is expected that biomimetic methods and water-soluble precursors like poly(vinyl alcohol) (PVA) for electrospinning will be utilized to solve the above problems. Inspired by the multistage water management process of a spider spinning dragline silk, we have established a combined biomimetic technique, hydrocolloid electrospinning coupled with temperature gradient dehydration, with a carbonization technique. PVA-driven superfoldable carbon nanofiber membranes (PVA-SFCNFMs) have been prepared that not only possess a >60% micropore ratio and a 1368.8 m2/g specific surface area but also can withstand 180° real folding for 100 000 cycles, approaching the thickness limit without structure fracture. Furthermore, these membranes provide highly sensitive sensing and superior biocompatible interfaces. The molecular mechanism to improve carbon conversion and the folding mechanism to obtain "three-level dispersing stress" for the PVA-SFCNFMs have been proposed.

In this work, three novel MgO-SiO2 composite catalysts with inverted structure have been synthesized via a facile and scalable strategy by means of the incipient wetness impregnation of the silica sol onto MgO precursors with different morphologies, and evaluated for the one-step conversion of ethanol to 1,3-butadiene. The prepared flower-like MgO-SiO2 composite catalysts exhibited highly enhanced catalytic activity than those catalysts synthesized from MgO precursors with nanodisks and nanosheets morphologies. Characterization results based on XRD, FT-IR, UV–vis, BET, CO2-TPD, NH3-TPD, ethanol-TPD, and 29Si MAS NMR revealed that unique layered flower-like architectures may facilitate the formation of interfacial Mg-O-Si chemical bond in binary MgO-SiO2 composite catalysts which are mainly responsible for the superior activity. This study presents a new strategy to design and develop the catalyst for efficient conversion of bio-ethanol to 1,3-butadiene by morphological control of MgO-SiO2 bifunctional catalysts.

Three ZnO supports with different morphologies (fusiform, nanoparticle and rod-shaped sphere) were synthesized successfully by facile hydrothermal method, over which Ag were loaded to evaluate for the hydrogen production in partial oxidation of methanol in the temperature range of 150–400 °C. The activity data showed that the catalytic activities of Ag/ZnO catalysts were markedly affected by the morphologies of the supporting materials, among which their activities ranked as fusiform > nanoparticle > rod-shaped sphere. The best performing AgZn-F catalyst shows the highly efficient catalytic performance, achieving almost 100% conversion and very low CO selectivity at 360 °C. These results illustrate that the morphology of support plays a crucial role on the Ag dispersion and the interaction of Ag and ZnO support, and thus determines the catalytic activity in partial oxidation of methanol.

Catalytic reduction of CO2 to methane has been recognized as one of the most important strategic reactions to produce highly valuable chemicals and for storage of renewable energy (power-to-gas). This study demonstrates a crystal facet-dependent catalytic reduction of CO2 to CH4 on ruthenium nanoparticles deposited over TiO2 nanocrystal with exposed (001) and (101) facets. Compared with TiO2 (101) nanocrystal with the same Ru loading, Ru nanoparticles supported by TiO2 (001) exhibited a highly enhanced CO2 conversion rate and significantly improved methanation reactivity, along with a considerable durability. The physicochemical properties of the samples were characterized by HR-TEM, XRD, BET, FT-IR, UV-vis, Raman, ICP, and temperature-programmed reaction with CO2, and CO2 + H2. In view of the difference in catalytic activity and the physicochemical properties of the supported Ru/TiO2 catalysts, the results uncovered that the nature of the catalyst support of Ru/TiO2 strongly affected the dispersion of Ru species and the synergistic effect between Ru and underlying TiO2 supporting materials due to the strong metal-support interaction, and thus affected their capability to activate CO2 and determined the catalytic activity for CO2 methanation. Our work demonstrated the important role of the exposed crystal facets of the underlying support and the resulting Ru particle which had a large effect on CO2 methanation.

A novel micro/mesoporous Si/O/C/N quaternary composite aerogels were prepared for the first time and possessed efficient synergistic effect of physisorption and chemisorption. In the preparation process, a simple sol-gel method was applied to integrating nitrogen rich chitosan sol and tetraethoxysilane (TEOS) sol skillfully. The 2 mm-thick Si/O/C/N composite adsorption layer was sandwiched into the acetate filter rod of control sample to form a test sample with high removal efficiency for volatile carbonyl compounds, especially for crotonaldehyde (75.9%) in mainstream cigarette smoke (MCS). The micro/mesoporous Si/O/C/N quaternary composite aerogels have brilliant prospect in the application of cigarette smoke filtration, water purification, etc.