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The prognosis for traumatic brain injury (TBI) depends largely on prompt hemostasis and effective pharmacologic interventions. Natural all‐small‐molecule self‐gelling powder, integrating the advantages of self‐assembled small‐molecule hydrogels and powders, is expected to provide timely and effective prehospital management of TBI. However, the synthesis and application of natural all‐small‐molecule self‐gelling powder is still uncharted territory. In this study, an all‐small‐molecule co‐assembled MGF‐H3BO3‐RUT (MBR) self‐gelling powder is fabricated through the co‐assembly of mangiferin (MGF) and rutin (RUT) in H3BO3/NaOH aqueous solution. Both compounds can bind with boric acid, leading to co‐assembling into hydrogels through hydrogen‐bonding interactions and π–π stacking. MBR self‐gelling powder is then obtained by drying the as‐prepared hydrogels, thus integrating hemostasis and pharmacodynamics into one. Remarkably, it displays robust regeneration capabilities, while retaining excellent self‐healing properties and injectability after drying‐hydration cycles. Moreover, MBR self‐gelling powder not only achieves rapid effective hemostasis but also attenuates conspicuously cerebral edema and inflammatory response after TBI by in situ spraying, exhibiting notable neuroprotective effects without discernible toxic side effects. This study provides a novel assembly strategy and application form for self‐assembled gel materials originating from natural small molecules, offering promising avenues for the treatment of TBI in the acute phase. [ABSTRACT FROM AUTHOR]

Recently, passive radiative cooling (PRC) that realizes thermal management without consuming any energy has attracted increasing attention. However, few studies focus on low‐cost and robust PRC film fabricated by a facile and environmentally friendly method. In this study, via coextrusion blow film molding and water leaching, sandwiched PRC film (SPRCF) is efficiently prepared, and its skin and core layer are respectively high‐density polyethylene (HDPE) film and oriented ZnO@HDPE microfiber layer. Of note, such a sandwiched structure enables SPRCF to possess remarkable mechanical properties, abrasion, and weather resistance. Moreover, with the introduction of ZnO, SPRCF shows lower sunlight transmittance (≈3.8%) but higher mid‐infrared transmittance (≈88.8%), endowing it with remarkable PRC performance (the maximum cooling power of daytime and nighttime are respectively 73.8 and 96.7 W m−2). Furthermore, the decent self‐cleaning performance of SPRCF‐45 endows it with maintenance‐free features outdoors. This work proposes a facile and environmentally friendly method for preparing low‐cost and robust SPRCF, opening a new pathway to develop PRC film following the concept of polymer "structuring" processing. [ABSTRACT FROM AUTHOR]

The addition of CaCO3 powder in calcium aluminate cement (CAC) is reported to accelerate the hydration of CAC and generate mono‐carbonate C4AC̅H11, which is conducive to shortening the curing time of CAC‐bonded castables at ambient temperatures. Although the hydration of CAC is relatively fast, there is still residual un‐hydrated CAC in castables after curing. The residual CAC would continue to hydrate to produce C3AH6 and AH3 during the subsequent drying procedures in the absence of CaCO3. But it is worth pondering which type of hydrate would be generated in the presence of CaCO3 during the drying at around 110°C. In this study, the effect of micro‐sized CaCO3 addition on the hydrate formation of CAC‐bonded castables during drying at 110°C was investigated. The results indicate that the C4AC̅H11 formed at the curing temperature of 30°C is not decomposed or converted during drying. The CaCO3 remained after curing does not participate in the hydration of residual CAC during drying at 110°C, and thus the residual CAC continues to hydrate to generate C3AH6 rather than C4AC̅H11. [ABSTRACT FROM AUTHOR]

Electromagnetic interference (EMI) shielding fabrics are crucial in addressing the increasingly serious electromagnetic pollution. To meet wearable requirements, stretchability and thermal comfortability are often desired, but which still are challenging. Herein, a stretchable EMI shielding fabric is fabricated via electrospinning coupled with biaxial pre‐stretching spraying, in which a block stacking wrinkled silver nanowire (AgNW)/Ti3C2Tx MXene network is coated on one side of electrospun thermoplastic polyurethane (TPU)/polydimethylsiloxane (PDMS) fabric. As expected, the wrinkled structure protects conductive network from fracture during stretching process, so as to realize the strain‐invariant electrical conductivity. Thus, the fabric exhibits a stretchable EMI shielding performance of over 40 dB when subjected to 10–50% uniaxial strains or 21–125% biaxial strains. More importantly, the white TPU/PDMS side and the black AgNW/MXene side enable the fabric passive radiative cooling and heating, respectively. The cooling side exhibits high mid‐infrared emissivity (97.5%) and solar reflectance (90%), thus reducing the skin temperature by ≈4.9 °C. The heating side with high solar absorptivity (86.6%) and photothermal effect increased the skin temperature by ≈5 °C. Therefore, the fabirc with stretchable EMI shielding and Janus‐type dual‐mode personal passive thermal management is promising in future wearable products. [ABSTRACT FROM AUTHOR]

Dendritic mesoporous silica nanoparticles own three‐dimensional center‐radial channels and hierarchical pores, which endows themselves with super‐high specific surface area, extremely large pore volumes, especially accessible internal spaces, and so forth. Dissimilar guest species (such as organic groups or metal nanoparticles) could be readily decorated onto the interfaces of the channels and pores, realizing the functionalization of dendritic mesoporous silica nanoparticles for targeted applications. As adsorbents and catalysts, dendritic mesoporous silica nanoparticles‐based materials have experienced nonignorable development in CO2 capture and catalytic conversion. This comprehensive review provides a critical survey on this pregnant subject, summarizing the designed construction of novel dendritic mesoporous silica nanoparticles‐based materials, the involved chemical reactions (such as CO2 methanation, dry reforming of CH4), the value‐added chemicals from CO2 (such as cyclic carbonates, 2‐oxazolidinones, quinazoline‐2,4(1H,3H)‐diones), and so on. The adsorptive and catalytic performances have been compared with traditional silica mesoporous materials (such as SBA‐15 or MCM‐41), and the corresponding reaction mechanisms have been thoroughly revealed. It is sincerely expected that the in‐depth discussion could give materials scientists certain inspiration to design brand‐new dendritic mesoporous silica nanoparticles‐based materials with superior capabilities towards CO2 capture, utilization, and storage. [ABSTRACT FROM AUTHOR]

In response to the increasing utilization of communication technology, there is a growing need for electromagnetic interference (EMI) shielding materials to adapt to diverse application scenarios. In this study, the self‐destructible EMI shielding films (SEFs) that possess the unique capability to reduce conductivity and shielding efficiency through temperature elevation are introduced. The SEFs effectively fulfill the requirement of triggering EMI shielding failure under specific conditions, which can be achieved by simply spraying a mixture of thermally expandable microspheres (TEMs), conductive fillers, and resin substrates. The segregated structures resulting from the incorporation of TEMs confer exceptional electrical conductivity and superior EMI shielding performance at low conductive filler content. When the ambient temperature surpasses the glass transition temperature of the TEM shell, the thermally expandable characteristics cause a disruption in the conductive path of the SEFs, leading to a significant decline in shielding effectiveness. Additionally, the SEFs exhibit outstanding Joule heating effects (90 °C) at low voltage (1.5 V) within a brief time frame (10 s). Importantly, when employed as Joule heaters, the SEFs possess an intrinsic safety mechanism that automatically ceases operation in the event of circuit overload, thus minimizing any potential risks. [ABSTRACT FROM AUTHOR]

Developing polymer‐based piezoelectric materials with multistimulus responsiveness is highly desirable for advancing multi‐source energy harvesting in wearable electronics. Inspired by the multifunctionality of muscle fibers, a nanostructure interface engineering strategy to create piezoelectric polymeric nanoheterostructures (PNHs) with remarkable responsiveness to both mechanical and nonmechanical contactless stimuli is introduced. Through precise interfacing of polymer nanofibers with nanoparticles via multiscale‐regulated interface electrostatic and chemical interactions, the study achieves a controlled assembly of stabilized and hierarchically organized nanoheterostructures featuring unique interface‐confined configurations. These configurations induce in situ stabilized dipole orientation and significant geometric stress nano‐confinement at interfaces, crucial for amplifying electricity generation. Compared to conventional polymer nanocomposites, engineered PNHs exhibit dramatically enhanced piezoelectricity, boasting a higher sensitivity of 1065 mV kPa−1 and piezoelectric coefficient of 76.2 pC N−1. Furthermore, PNHs demonstrate superior thermo‐actuated electricity generation under temperature fluctuations through cooperative spontaneous polarizations of constituent nanostructures, yielding a higher pyroelectric coefficient of 3.13 µC m2K−1. Additionally, the design enables photothermally‐activated switchable electricity generation and light‐energy harvesting, achieving a photo‐electric conversion efficiency tenfold higher than nanocomposites. This effective and versatile approach inspires the development of multi‐responsive nanogenerators for multi‐energy harvesting and self‐powered multistimulus‐sensing applications. [ABSTRACT FROM AUTHOR]

Enhancing the piezoelectricity of polymers while maintaining all components organic is still challenging but significantly important for developing flexible wearable energy harvesters and self‐powered devices. Here, a novel and versatile strategy is introduced to construct mixed‐dimensional all‐organic polymer heterostructures (MPHs) for enhanced piezoelectricity. By combining all‐polymer 1D nanofibers (NFs) with 2D crystals through epitaxial crystallization‐driven assembly (ECA), MPHs are engineered to capitalize on the synergistic effects of both dimensional nanostructures. The intrinsic piezoelectric activity of 1D NFs is amplified by the growth of 2D crystals, enhancing force‐sensitivity and overall piezoelectricity. The mixed‐dimensional assembly not only enables controlled in‐situ growth of MPHs, but also simultaneously induces preferential formation of electroactive phases through solvent‐induced phase transition. By modulating the epitaxial growth of 2D crystals on 1D NFs, effective tuning of MPH growth amount and morphology is achieved, resulting in significant improvements in deformability, dipole polarization, and durability. MPHs exhibit remarkable piezoelectric improvements, achieving higher output under lower‐level forces with a record‐high sensitivity of ≈670 mV kPa−1. Their superior responsivity enables the development of self‐powered wireless wearable motion‐monitoring systems for real‐time physiological movement detection and analysis. This work inspires the development of all‐organic piezoelectric devices for innovative flexible energy‐harvesting and sensing applications. [ABSTRACT FROM AUTHOR]

Conductive hydrogels are gaining significant attention as promising candidates for the fabrication materials for flexible electronics. Nevertheless, improving the tensile properties, hysteresis, durability, adhesion, and electrochemical properties of these hydrogels remains challenging. This work reports the development of a novel semi‐interpenetrating network poly(ionic liquid) hydrogel named PATV, via the in situ polymerization of acrylamide, N‐[Tris(hydroxymethyl)methyl] acrylamide, and 1‐vinyl‐3‐butylimidazolium tetrafluoroborate. The density functional theory calculations reveal that the poly(ionic liquid) in the hydrogel network acts as physical cross–linking points to construct hydrogen‐bond networks. Furthermore, the hydrogen‐bond networks dissipate energy efficiently and quickly, and thus stress concentration and hysteresis are avoided. The prepared hydrogel has a low hysteresis (9%), high tensile properties (900%), fast response (180 ms), high sensitivity (gauge factor = 10.4, pressure sensitivity = 0.14 kPa−1), and wide sensing range (tensile range: 1–600%, compression range: 0.1–20 kPa). A multifunctional sensor designed based on the designed hydrogel enables real‐time, rapid, and stable response‐ability for the detection of human movement, facial expression recognition, pronunciation, pulse, handwriting, and Morse code encryption. Furthermore, the assembled triboelectric nanogenerator displays an excellent energy harvesting capability, thus highlighting its potential application in self‐powered flexible wearable electronic devices. [ABSTRACT FROM AUTHOR]

Highlights In this paper, a hybrid approach was employed by integrating a high‐modulus, high‐tensile‐strength carbon fiber fabric (CFF) with a low‐density, high‐toughness silk nonwoven fabric (SNWF) to fabricate CFF‐SNWF reinforced epoxy (CFF‐SNWF/EP) hybrid composites. Through the surface freeze‐induced self‐assembly process, the multiscale hybrid modified layers were successfully constructed on the surfaces of both CFF and SNWF. This novel approach effectively enhanced the interfacial strength of the hybrid fibers (HFs). Comparing the performance of the modified composites with unmodified CFF reinforced epoxy (CFF/EP), significant improvements in both tensile strength and interlaminar shear strength were observed. Specifically, the tensile strength and interlaminar shear strength of the modified composites reached 626.7 and 39.16 MPa, a rise scope of 17.1% and 14.8%, respectively. In addition, the hybrid fibers reinforced polymers (HFRPs) exhibited a superior electromagnetic interference (EMI) shielding capabilities. For insistence, the modified CFF/EP with a thickness of 2.0 mm showed an impressive EMI shielding effectiveness value of 50 dB. These findings underscore the promising application potential of CFF‐SNWF/EP hybrid composites, particularly in the field of consumer electronics. The surface of hybrid fiber was modified by PDA‐GO‐OCNTs‐WPU. Multi‐scale structure contributes a lot in composite performance. Hybrid effect before and after interfacial modification is performed. The hybrid interface modification and hybrid structure were analyzed. [ABSTRACT FROM AUTHOR]