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The 2D/1D/0D Ti 3 C 2 T x /carbon nanotubes/Co nanocomposite is successfully synthesized via an electrostatic assembly.Nanocomposites exhibit an excellent electromagnetic wave absorption and a remarkable electromagnetic interference shielding efficiency.The flexible, waterproof, and photothermal conversion performances are achieved.ABSTRACT High-performance electromagnetic wave absorption and electromagnetic interference (EMI) shielding materials with multifunctional characters have attracted extensive scientific and technological interest, but they remain a huge challenge. Here, we reported an electrostatic assembly approach for fabricating 2D/1D/0D construction of Ti 3 C 2 T x /carbon nanotubes/Co nanoparticles (Ti 3 C 2 T x /CNTs/Co) nanocomposites with an excellent electromagnetic wave absorption, EMI shielding efficiency, flexibility, hydrophobicity, and photothermal conversion performance. As expected, a strong reflection loss of -85.8 dB and an ultrathin thickness of 1.4 mm were achieved. Meanwhile, the high EMI shielding efficiency reached 110.1 dB. The excellent electromagnetic wave absorption and shielding performances were originated from the charge carriers, electric/magnetic dipole polarization, interfacial polarization, natural resonance, and multiple internal reflections. Moreover, a thin layer of polydimethylsiloxane rendered the hydrophilic hierarchical Ti 3 C 2 T x /CNTs/Co hydrophobic, which can prevent the degradation/oxidation of the MXene in high humidity condition. Interestingly, the Ti 3 C 2 T x /CNTs/Co film exhibited a remarkable photothermal conversion performance with high thermal cycle stability and tenability. Thus, the multifunctional Ti 3 C 2 T x /CNTs/Co nanocomposites possessing a unique blend of outstanding electromagnetic wave absorption and EMI shielding, light-driven heating performance, and flexible water-resistant features were highly promising for the next-generation intelligent electromagnetic attenuation system.

Cross-linked polymer particles were prepared via surfactant-free emulsion copolymerization of 2-(diethylamino)ethyl methacrylate (DEAEMA) and sodium methacrylate (SMA) using N,N'-methylenebis(acrylamide) (MBA) as a cross-linker. Generated particles are zwitterionic, possessing unique isoelectric points in the pH range of 7.5-8.0, which is readily tunable through CO2/N2 bubbling. The particles were found to be highly responsive to CO2/N2 switching, dissolving in water with CO2 bubbling and precipitating with N2 bubbling at room temperature. Pickering emulsions of n-dodecane were prepared using these particles as the sole emulsifier. These emulsions can be rapidly demulsified with CO2 bubbling, resulting in complete oil/water phase separations. Nitrogen bubbling efficiently re-emulsifies the oil with the aid of homogenization. The rapid emulsification/demulsification using CO2/N2 bubbling at room temperature provides these cross-linked zwitterionic particles with distinct advantages as functional Pickering surfactants.

Both poly(lactic acid) (PLA) and poly(butylene adipate-co-terephthalate) (PBAT) are fully biodegradable polyesters. The disadvantages of poor mechanical properties of PLA limit its wide application. Fully biodegradable polymer blends were prepared by blending PLA with PBAT. Crystallization behavior of neat and blended PLA was investigated by differential scanning calorimetry (DSC), polarizing optical microscopy (POM), and wide angle X-ray diffraction (WAXD). Experiment results indicated that in comparison with neat PLA, the degree of crystallinity of PLA in various blends all markedly was increased, and the crystallization mechanism almost did not change. The equilibrium melting point of PLA initially decreased with the increase of PBAT content and then increased when PBAT content in the blends was 60 wt % compared to neat PLA. In the case of the isothermal crystallization of neat PLA and its blends at the temperature range of 123-142 C, neat PLA and its blends exhibited bell shape curves for the growth rates, and the maximum crystallization rate of neat PLA and its blends all depended on crystallization temperature and their component.

Electromagnetic pollution has been causing a series of problems in people's life, and electromagnetic absorbers with lightweight and broad absorbing bandwidth properties are widely desired. In this work, novel sandwich-like 2D laminated Fe&TiO 2 nanoparticles@C nanocomposites were rationally designed and successfully developed from the MXene-MOFs hybrids. The formation of Fe and rutile-TiO 2 nanoparticles sandwiched by the two-dimensional carbon nanosheets provided strong electromagnetic energy attenuation and good impedance matching for electromagnetic wave (EMW) absorption. As expected, the nanocomposites achieved a broad effective absorption bandwidth of 6.5 GHz at a thickness of only 1.6 mm and the minimum reflection loss (RL) value of − 51.8 dB at 6.6 GHz with a thickness of 3 mm. This work not only provides a good design and fabricating concept for the laminated metal and functional nanoparticles@C nanocomposites with good EMW absorption, but also offers an important guideline to fabricate various two-dimensional nanocomposites derived from the MXene precursors.

Extracellular vesicles (EVs) curb important biological functions. We previously disclosed that ischemia‐reperfusion (IR) induces increased release of EVs (IR‐EVs) in the heart. However, the role of IR‐EVs in IR pathological process remains poorly understood. Here we found that adoptive transfer of IR‐EVs aggravated IR induced heart injury, and EV inhibition by GW4869 reduced the IR injury. Our in vivo and in vitro investigations substantiated that IR‐EVs facilitated M1‐like polarization of macrophages with increased expression of proinflammatory cytokines. Further, we disclosed the miRNA profile in cardiac EVs and confirmed the enrichment of miRNAs, such as miR‐155‐5p in IR‐EVs compared to EVs from the sham heart (S‐EVs). In particular, IR‐EVs transferred miR‐155‐5p to macrophages and enhanced the inflammatory response through activating JAK2/STAT1 pathway. Interestingly, IR‐EVs not only boosted the local inflammation in the heart, but even triggered systemic inflammation in distant organs. Taken together, we newly identify an IR‐EVs–miR‐155‐5p – M1 polarization axis in the heart post IR. The EVs derived from IR‐injured heart contribute to both local and systemic inflammation. Importantly, EV inhibition by GW4869 is supposed to be a promising therapeutic strategy for IR injury.

With the progressive requirements of modern electronics, outstanding electromagnetic interference (EMI) shielding materials are extensively desirable to protect intelligent electronic equipment against EMI radiation under various conditions, while integrating functional applications. So far, it remains a great challenge to effectively construct thin films with diversiform frameworks as integrated shielding devices. To simultaneously promote electromagnetic waves (EMWs) attenuation and construct integrated multifunction, an alternating-layered deposition strategy is designed to fabricate polydimethylsiloxane packaged Ndoped MXene (Ti 3 CNT x )/graphene oxide wrapped hollow carbon fiber/silver nanowire films (p-LMHA) followed by annealing and encapsulation approaches. Contributed by the synergistic effect of consecutively conductive networks and porous architectures, LMHA films exhibit satisfying EMI shielding effectiveness of 73.2 dB at a thickness of 11 μm, with a specific EMI shielding effectiveness of 31 150.1 dB•cm 2 •g −1 . Benefiting from the encapsulation, p-LMHA films further impart hydrophobicity and reliability against harsh environments. Besides, p-LMHA devices integrate a rapid-response behavior of the electro/photothermal and, meanwhile, function as a healthcare monitoring sensor. Therefore, it is believed that the p-LMHA films assembled by independent conductive networks with reliability offer a facile solution for practical multimodular protection of devices with integration characteristics.

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