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Graphene aerogel is a promising electromagnetic interference (EMI) shielding material because of its light weight, excellent electrical conductivity, uniform three-dimensional (3D) microporous structure, and good mechanical strength. The graphene aerogel with high EMI shielding performance is attracting considerable critical attention. In this study, a novel procedure to fabricate high EMI shielding graphene aerogel was presented, inspired by the irreversible deformation of hydrogels under mechanical pressure. The procedure involved a mechanical compression step on graphene hydrogels for the purpose of altering microstructures followed by freeze-drying and thermal annealing at 900 °C to generate the final products. Because of the flow of internal liquid caused by mechanical compression, the microstructures of hydrogels changed from a cellular configuration to a layered configuration. After a high degree of compression, GAs can be endowed with homogeneous layered structure and high density, which plays a leading role in electromagnetic wave dissipation. Consequently, the aerogels with excellent electrical conductivity (181.8 S/m) and EMI shielding properties (43.29 dB) could be obtained. Besides, the compression process enabled us to form complex hydrogel shapes via different molds. This method enhances the formability of graphene aerogels and provides a robust way to control the microstructure.Tough adhesive hydrogels that can tightly bond to wet tissue/polymer/ceramic/metal surfaces have great potentials in various fields. However, conventional adhesive hydrogels usually show short-term and nonreversible adhesion ability, as the water component in a hydrogel readily transforms to vapor or ice in response to fluctuation of environment temperature, hindering their applications in extreme conditions such as in freezing Arctic and roasting Africa. For the first time, urushiol (UH), a natural catechol derivative with a long alkyl side chain, is used as a starting material to copolymerize with acrylamide for fabricating adhesive hydrogels, which contain hydrophobic/hydrophilic moieties, antifreezing agent, and adhesive catechol groups. The antifreezer/moisturizer glycerol/water binary solvent dispersed in the hydrogel endows it with antifreezing/antiheating property. The hydrophobic association and π-π interaction from UH moieties of the copolymer greatly improve its mechanical strength (tensile stress ∼0.12 MPa with strain of ∼1100%, toughness ∼72 kJ/m3, compression stress ∼6.72 MPa at strain of 90%). The hydrogel can strongly adhere to various dry/wet biological/polymeric/ceramic/metallic substrates at temperatures ranging from -45 to 50 °C. Under ambient conditions, its adhesion force to porcine skin, glass, and tinplate may reach up to 160, 425, and 275 N/m, respectively. Even stored at -45 or 50 °C for 30 d, the hydrogel still maintains good flexibility and robust adhesion force. It also shows repeatable underwater adhesion to biological tissue, glass, ceramic, plastic, and rubber. This novel antifreezing/antiheating adhesive hydrogel may be applied in extremely cold or hot environments and in underwater conditions.The development of science and technology is accompanied by a complex composition of multiple pollutants. Conventional passive separation processes are not sufficient for current industrial applications. The advent of active or responsive separation methods has become highly essential for future applications. In this work, we demonstrate the preparation of a smart electrically responsive membrane, a poly(vinylidene difluoride) (PVDF)-graphene composite membrane. The high graphene content induces the self-assembly of PVDF with a high β-phase content, which displays a unique self-piezoelectric property. Additionally, the membrane exhibits excellent electrical conductivity and unique capacitive properties, and the resultant nanochannels in the membrane can be reversibly adjusted by external voltage applications, resulting in the tailored gas selectivity of a single membrane. After the application of voltage to the membrane, the permeability and selectivity toward carbon dioxide increase simultaneously. Moreover, atomic-level positron annihilation spectroscopic studies reveal the piezoelectric effect on the free volume of the membrane, which helps us to formulate a gas permeation mechanism for the electrically responsive membrane. Overall, the novel active membrane separation process proposed in this work opens new avenues for the development of a new generation of responsive membranes.Layer-structured black phosphorus (BP) demonstrating high specific capacity has been viewed as a very promising anode material for future high-energy-density Li-ion batteries (LIBs). However, its practical application is hindered by large volume change of BP and poor mechanical stability of BP anodes by traditional slurry casting technology. selleck products Here, a free-standing flexible anode composed of BP nanosheets and nanocellulose (NC) nanowires is fabricated via a facile vacuum-assisted filtration approach. The constructed free-standing BP@NC composite anode offers three-dimensional (3D) mixed-conducting network for Li+/e- transports. The substrate of NC film has a certain flexibility up to 10.2% elongation that can restrain the volume change of BP and electrode during operation. In addition, molecular dynamic (MD) simulation and density function theory (DFT) show the greatly enhanced Li+ diffusion in BP@NC composite where the Li ions receive less repulsive force at the interface of BP interlayer and nanocellulose. Benefiting from above multifunction of nanocellulose, the BP@NC composite exhibits high capacities of 1020.1 mAh g-1 at 0.1 A g-1 after 230 cycles and 994.4 mAh g-1 at 0.2 A g-1 after 400 cycles, corresponding to high capacity retentions of 87.1% and 84.9%, respectively. Our results provide a low-cost and effective strategy to develop advanced electrodes for next-generation rechargeable batteries.The growing enthusiasm to mimic the luminous properties of fluorescent proteins (FPs) has expanded to include the potential biomedical applications of FP analogues. We developed a series of non-fluorescent oligopeptides (Fc-(X)n; where X = F, Y, W, and H; n = 1-3) that can aggregate into fluorescent nanoparticles with rainbow colors, termed the peptidyl rainbow kit (PRK). The PRK encompasses the full visible color spectrum, and its photoluminescent properties may have originated from aggregation-induced emission (AIE). Intermolecular forces restricted the intramolecular motions of the oligopeptide residues, providing a barrier to non-radiative conformational relaxation pathways and leading to AIE fluorescence. The PRK oligopeptides are pH sensitive, biocompatible, and photostable under physiological conditions, making the PRK a promising fluorescence candidate for biomedical applications.
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