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We study self-affine tiles generated by iterated function systems consisting of affine mappings whose linear parts are defined by different matrices. We obtain an interior theorem for these tiles. We prove a tiling theorem by showing that for such a self-affine tile, there always exists a tiling set. We also obtain a more complete interior theorem for reptiles, which are tiles obtained when the matrices in the iterated function system are similarities. Our results extend some of the classical ones by Lagarias and Wang (Adv. Math. 121(1), 21–49 (1996)), where the IFS maps are defined by a single matrix. [ABSTRACT FROM AUTHOR]

For x ∈ [ 0 , 1 ] , the run-length function r n (x) is defined as the length of longest run of 1’s among the first n dyadic digits in the dyadic expansion of x. We study the Hausdorff dimension of the exceptional set in Erdös–Rényi limit theorem. Let φ : N → (0 , ∞) be a monotonically increasing function with lim n → ∞ φ (n) = ∞ and 0 ≤ α ≤ β ≤ ∞ , define E α , β φ = { x ∈ [ 0 , 1 ] : lim inf n → ∞ r n (x) φ (n) = α , lim sup n → ∞ r n (x) φ (n) = β }. We prove that E α , β φ has Hausdorff dimension one if lim n , p → ∞ φ (n + p) - φ (n) p = 0 and that E 0 , ∞ φ is residual in [0,1] when lim inf n → ∞ φ (n) n = 0 . [ABSTRACT FROM AUTHOR]

The author of this paper and coauthors in 2022 studied a family of self-affine tiles in R d with noncollinear digit sets, and gave a sufficient and necessary condition for such tiles to be tame balls. We in this paper mainly present a simpler proof of such equivalent condition. We replace quadric surfaces by some zigzag planes, and redefine the quasi-invariant plane which plays a key role in the construction of the desired homeomorphism. This adjustment greatly simplifies the proof. [ABSTRACT FROM AUTHOR]

In this paper, we study topological properties of some level sets and some multifractal sets induced by Rademacher's series and Takagi's series, respectively. By using symbolic space, we obtain necessary and sufficient conditions for them to be residual. [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]

Self-similarity and Lipschitz equivalence are two basic and important properties of fractal sets. In this paper, we consider those properties of the union of Cantor set and its translate. We give a necessary and sufficient condition that the union is a self-similar set. Moreover, we show that the union satisfies the strong separation condition if it is of the self-similarity. By using the augment tree, we characterize the Lipschitz equivalence between Cantor set and the union of Cantor set and its translate. [ABSTRACT FROM AUTHOR]

In this study, the influence of multiwalled carbon nanotubes (MWCNT) on β‐isotactic polypropylene (iPP) formation in preshear injection‐molded iPP/MWCNT nanocomposites is investigated layer by layer by wide angle X‐ray diffraction (WAXD). WAXD results suggest that in preshear injection‐molded pure iPP, β‐iPP exists in not only the shear region, but also the core region as a result of preshear‐induced nucleation. The addition of MWCNT can inhibit the β‐iPP formation. As the depth away from the specimen surface is decreased, the inhibiting effect is decreased. The reason responsible for that is given as follows: (1) with the addition of MWCNT, extra nuclei are induced during preshear. Both MWCNT and extra nuclei serve as α‐iPP nucleation point. Therefore, the formation of β‐iPP is restricted; (2) the cooling rate gradient is widely accepted to exist in the injection molded sample. A larger cooling rate at a smaller depth will give rise to a lower α‐iPP crystallization onset temperature and a lower nucleation efficiency of MWCNT. Since that β‐iPP grows only in the temperature range of 105°C‐140°C, the inhibiting effect of MWCNT on β‐iPP becomes weaker as the depth is decreased. POLYM. COMPOS., 39:E1149–E1158, 2018. © 2017 Society of Plastics Engineers [ABSTRACT FROM AUTHOR]

We study a family of self-affine tiles in R d (d ≥ 2) with noncollinear digit sets, which naturally generalizes a two-dimensional class studied originally by Deng and Lau and its extension to R 3 by the authors. By using Brouwer's invariance of domain theorem, along with a tool which we call horizontal distance, we obtain necessary and sufficient conditions for the tiles to be d -dimensional tame balls. This answers positively the conjecture in an earlier paper by the authors stating that a member in a certain class of self-affine tiles is homeomorphic to a d -dimensional ball if and only if its interior is connected. [ABSTRACT FROM AUTHOR]

A wide spectrum of state-of-the-art characterization techniques have been devised to monitor the electrode–electrolyte interface that dictates the performance of electrochemical devices. However, coupling multiple characterization techniques to realize in situ multidimensional analysis of electrochemical interfaces remains a challenge. Herein, we presented a hyphenated differential electrochemical mass spectrometry and attenuated total reflection surface enhanced infrared absorption spectroscopy analytical method via a specially designed electrochemical cell that enables a simultaneous detection of deposited and volatile interface species under electrochemical reaction conditions, especially suitable for non-aqueous, electrolyte-based energy devices. As a proof of concept, we demonstrated the capability of the homemade setup and obtained the valuable reaction mechanisms, by taking the tantalizing reactions in non-aqueous lithium-ion batteries (i.e., oxidation and reduction processes of carbonate-based electrolytes on Li1+xNi0.8Mn0.1Co0.1O2 and graphite surfaces) and lithium-oxygen batteries (i.e., reversibility of the oxygen reaction) as model reactions. Overall, we believe that the coupled and complementary techniques reported here will provide important insights into the interfacial electrochemistry of energy storage materials (i.e., in situ, multi-dimensional information in one single experiment) and generate much interest in the electrochemistry community and beyond. [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]

Highlights: The SiO2 nanofiber membranes and MXene@c-MWCNT6:4 as one unit layer (SMC1) were bonded together with 5 wt% PVA solution. When the structural unit is increased to three layers, the resulting SMC3 has an average electromagnetic interference SET of 55.4 dB and a low thermal conductivity of 0.062 W m−1 K−1. SMCx exhibit stable electromagnetic interference shielding and excellent thermal insulation even in extreme heat and cold environment. A lightweight flexible thermally stable composite is fabricated by combining silica nanofiber membranes (SNM) with MXene@c-MWCNT hybrid film. The flexible SNM with outstanding thermal insulation are prepared from tetraethyl orthosilicate hydrolysis and condensation by electrospinning and high-temperature calcination; the MXene@c-MWCNTx:y films are prepared by vacuum filtration technology. In particular, the SNM and MXene@c-MWCNT6:4 as one unit layer (SMC1) are bonded together with 5 wt% polyvinyl alcohol (PVA) solution, which exhibits low thermal conductivity (0.066 W m−1 K−1) and good electromagnetic interference (EMI) shielding performance (average EMI SET, 37.8 dB). With the increase in functional unit layer, the overall thermal insulation performance of the whole composite film (SMCx) remains stable, and EMI shielding performance is greatly improved, especially for SMC3 with three unit layers, the average EMI SET is as high as 55.4 dB. In addition, the organic combination of rigid SNM and tough MXene@c-MWCNT6:4 makes SMCx exhibit good mechanical tensile strength. Importantly, SMCx exhibit stable EMI shielding and excellent thermal insulation even in extreme heat and cold environment. Therefore, this work provides a novel design idea and important reference value for EMI shielding and thermal insulation components used in extreme environmental protection equipment in the future. [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]

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]

The characterization of the impact strength and structure of bisphenol A polycarbonate aged in 65°C H2SO4 aqueous solutions (pH = 4.5) and in distilled water, both at 65°C, was carried out by means of impact testing, Differential Scanning Calorimetry (DSC), Fourier Transform Infrared Spectroscopy (FTIR), Polarizing Microscopy (POM) and Scanning Electron Microscopy (SEM) measurements. The results were as follows: the impact strength increased a little (from 71 to 76.3 kJ/m2) after being aged 1 day in the H2SO4 aqueous solution. Microvoids were formed on the surface of the PC in both the aqueous solution and distilled water aging, and the size and number of the microvoids increased substantially with the increase of aging time. The glass transition temperature showed a slight decrease after aging. In both liquids, the degradation mechanism was ascribed to the hydrolysis of ester groups in both aqueous solutions aging. However, the hydrolysis rate of PC aged in hot water was higher than that of the sample aged in the H2SO4 aqueous solution in the first day of aging. In addition, a ductile failure to brittle failure transition was observed for both H2SO4 solution and hot water aging. [ABSTRACT FROM AUTHOR]

Thermosetting polyimide (PI) foams (PIFs) are usually synthesized through chemical foaming; however, this approach is environmentally toxic, and it is difficult to regulate the cell structure, remold the foam, and increase the foam compressive strength. The development of microcellular PIFs with ultrahigh compressive strength and high volume expansion ratio remains a challenge. Herein, thermoplastic PI with a branched structure and flexible ether bonds was synthesized through solution polymerization, and microcellular thermoplastic PIFs (TPIFs) with ultrahigh strength were fabricated via supercritical-carbon-dioxide foaming using 2,4,6-triamino pyrimidine (TAP) as a chain-extender monomer. Subsequently, a lattice model of a closed tetrakaidecahedral cell was used to clarify the relation between the foam compressive strength and polymer cell structure. Experimental results indicate that the optimal thermal imidization temperature is 230 °C and that the resulting branched structure considerably improves viscoelasticity, flame retardancy, and foaming performance. A TAP content of 0.75 g results in branched-structure TPIFs with a mean cell size of 16.8 μm. Notably, at high temperatures and pressures, the compressive strength of TPIFs with 0.75 g TAP is more than nine times of that of TPIFs without TAP. Increasing the TAP content beyond 0.75 g results in a crosslinked structure. Backward differentiation shows that TPIF compression is constant at 0.14–0.18 in the [0,0,1] lattice direction. The proposed physical foaming method is environment-friendly and can sustainably produce TPIFs with a high volume expansion ratio, an adjustable microcellular structure, and outstanding mechanical properties. [Display omitted] • Branched thermoplastic polyimide (TPI) synthesized via solution polymerization. • TPI offers superb flame resistance and recyclability for fireproofing. • Microcellular TPI foams are fabricated by supercritical CO 2 foaming. • TPI foams exhibit uniform structure and strong compressive strength. • Lattice model clarifiies the relationship between compressive strength and polymer cell structure. [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]

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]

Polylactic acid (PLA) aerogels with spider network structure, bead-like connected microsphere structure, and cluster petal structure were fabricated by precisely controlling the phase separation behavior (nucleation growth and spinodal separation) of the ternary solution system. The PLA aerogel with ideal spider network structure achieved an extremely high porosity of 96% and a high specific surface area of 114 m2/g, which rendered it with excellent triboelectric energy generation performance. [Display omitted] Aerogels with 3D porous structures have been attracting increasing attention among functional materials due to their advantages of being lightweight and high specific surface area. Precise control of the porous structure of aerogel is essential to improve its performance. In this work, polylactic acid (PLA) aerogels with distinctly different microstructures were fabricated by precisely controlling the phase separation behavior of the ternary solution system. Rheological and theoretical analyses have revealed that the interactions between polymer molecules, solvents and non-solvents play a crucial role in determining the nucleation and growth of poor olymer and rich polymer phases. By adjusting the non-solvent type and the solution composition, aerogels with spider network structure, bead-like connected microsphere structure, and cluster petal structure were obtained. Ideal spinodal phase separation conditions were obtained to produce aerogels with a homogeneous fiber network structure. The optimum PLA aerogel achieved an extremely porosity of 96 % and a high specific surface area of 114 m2/g, which rendered it with excellent triboelectric generation performance. Thus, this work provides fundamental insights into the precise regulation of the phase separation behavior and the structure of the aerogel, which can help boost the performance and expand the applications of PLA aerogels. [ABSTRACT FROM AUTHOR]

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 use of antibacterial biodegradable polymers is of great importance nowadays in medical applications. In this manuscript, poly(butylenes adipate-co-terephthalate)/poly(lactic acid) blend-based antibacterial bionanocomposites were prepared by melt-processing. We use organically modified montmorillonite (MMT) and graphene nanoplatelets (GNP) as antibacterial property enhancers which are both processing platelike structure, while ciprofloxacin hydrochloride (CFX·HCl) was chosen as a biocide. Either MMT or GNP increases the antibacterial properties during the whole study and tunes the release of CFX·HCl from the bionanocomposites. This was proven by agar diffusion tests and antimicrobial release measurements. The morphology of the bionanocomposites was conducted by using scanning and transmission electron microscopies, and evidence of exfoliation was observed. Contact angle and water uptake of the bionanocomposites were studied showing hydrophilic performance and more percentage water uptake. The final effect on mechanical and blood compatibility was also investigated. The results reveal excellent possibility of using MMT- and GNP-modified PLA/PBAT polymer blends to tune antibacterial properties for specific biomedical applications. [ABSTRACT FROM AUTHOR]

[Display omitted] Ultrathin MXene composite films, with their flexibility, metal-level conductivity, and multifunction compatibility, are an ideal choice for electromagnetic interference (EMI) shielding materials in future developments. Nonetheless, the dilemma between electrical conductivity and robustness in these composite films remains a challenge. Herein, an ammonium polyphosphate (APP) assisted interfacial multiple cross-linking strategy, achieved via simple solution blending and filtration, was employed to reinforce and toughen the "brick–mortar" layered MXene/bacterial cellulose (MBCA) films without compromising their conductivity and EMI shielding ability. The introduction of a small amount of APP leads to multiple interfacial interactions between MXene and bacterial cellulose, resulting in significant enhancements in mechanical strength (360.8 MPa), Young's modulus (2.8 GPa), fracture strain (17.3%), and toughness (34.1 MJ/m3). Concurrently, the MBCA film displayed satisfactory conductivity values of 306.7 S/cm and an EMI SE value of 41 dB upon optimizing the MXene content. Additionally, the MBCA film demonstrated a consistent, rapid-response photothermal conversion capability, achieving a photothermal conversion temperature of 97 °C under a light intensity of 200 mW/m2. Consequently, this tough and multifunctional EMI shielding film holds substantial promise for protecting electronic equipment. [ABSTRACT FROM AUTHOR]

Patients with metabolic syndrome (MetS) undergoing surgery are at high risk of developing peritoneal adhesions and other severe postoperative complications. However, the single shielding function and absence of physiological activity render conventional methods less useful in preventing adhesions in patients with MetS. To address this challenge, a convenient method is introduced for developing a novel tissue‐adhesive hydrogel called oxidized dextran–metformin (ODE–ME) via Schiff base linkages. This injectable ODE–ME hydrogel exhibits excellent tissue‐adhesive properties and various physiological functions, particularly enhanced antibacterial effects. Furthermore, in vivo experiments demonstrate that the hydrogel can effectively alleviate hyperglycemia, reduce excessive inflammation, and improve fibrinolytic activity in MetS mice, thereby preventing adhesions and promoting incisional healing. The hydrogel concurrently isolates injured tissues and lowers the blood glucose levels immediately after surgery in mice. Therefore, the ODE–ME hydrogel functions as a multifunctional barrier material and has potential for preventing postoperative peritoneal adhesions in patients with MetS in clinical settings. [ABSTRACT FROM AUTHOR]

The development of flexible and adaptable multifunctional sensing systems for human–machine interaction, especially for animal voice‐emotion identification, is highly desirable yet quite challenging. Herein, a multifunctional triboelectric nanogenerator (TENG) based on ordered hierarchical microhump arrays is proposed and fabricated by template‐assisted electrospinning with a facile, low‐cost, and expandable manufacturing process. Performances of a single‐electrode TENG based on the patterned nanofiber films with microhump arrays (NFM‐TENG) are studied in detail by varying mesh number of the template. Electric field structure of the collector is altered by pore sizes, wire diameters, and protrusions of the receiving templates subjected to different mesh numbers, generating different degrees of microhump arrays on the surface of the nanofiber film. NFM‐TENG demonstrates high sensitivity (15.94 mV Pa−1), fast response and recovery time (76 and 58 ms), a large power density of 122 mW m−2, and excellent ability of structural retention. Integrated with four functions of energy harvesting, pressure sensing, human physiological sensing, and animal voice‐emotion identification, NFM‐TENG achieves real‐time monitoring of human physiological, motion, handwriting, and animal voice‐emotion signals without an external power supply. This study shows significant application strategies for self‐powered human–machine interaction devices, novel animal voice‐emotion identification, biodiversity conservation, and so on. [ABSTRACT FROM AUTHOR]

[Display omitted] • A flocculation and in-situ solidification strategy for soluble polysulfides is proposed by using antistatic agent SN. • SN shows strong charge and bonding interactions with soluble polysulfides to inhibit the shuttle effect. • Multifunctionalities of catalytic effect and enhanced lithium-anode protection are demonstrated. • With 0.1 wt% SN addition, an ultra-low capacity decay rate of 0.014 % per cycle is obtained for cells cycled at 2C. Lithium-sulfur batteries (LSBs) are among the most promising next-generation high energy density energy-storage systems. However, practical application has been hindered by fundamental problems, especially shuttling by the higher-order polysulfides (PSs) and slow redox kinetics. Herein, a novel electrolyte-based strategy is proposed by adding an ultrasmall amount of the low-cost and commercially available cationic antistatic agent octadecyl dimethyl hydroxyethyl quaternary ammonium nitrate (SN) into a routine ether electrolyte. Due to the strong cation–anion interaction and bridge-bonding with SN, rapid flocculation of the soluble polysulfide intermediates into solid-state polysulfide-SN sediments is found, which significantly inhibited the adverse shuttling effect. Moreover, a catalytic effect was also demonstrated for conversion of the polysulfide-SN intermediates, which enhanced the redox kinetics of Li–S batteries. Encouragingly, for cells with only 0.1 % added SN, an initial specific capacity of 783.6 mAh/g and a retained specific capacity of 565.7 mAh/g were found at 2C after 200 cycles, which corresponded to an ultralow capacity decay rate of only 0.014 % per cycle. This work may provide a simple and promising regulation strategy for preparing highly stable Li–S batteries. [ABSTRACT FROM AUTHOR]

C2N is a unique member of the CnNm family (carbon nitrides), i.e., having a covalent structure that is ideally composed of carbon and nitrogen with only 33 mol% of nitrogen. C2N, with a stable composition, can easily be prepared using a number of precursors. Moreover, it is currently gaining extensive interest owing to its high polarity and good thermal and chemical stability, complementing carbon as well as classical carbon nitride (C3N4) in various applications, such as catalysis, environmental science, energy storage, and biotechnology. In this review, a comprehensive overview on C2N is provided; starting with its preparation methods, followed by a fundamental understanding of structure–property relationships, and finally introducing its application in gas sorption and separation technologies, as supercapacitor and battery electrodes, and in catalytic and biological processes. The review with an outlook on current research questions and future possibilities and extensions based on these material concepts is ended. [ABSTRACT FROM AUTHOR]

Conductive hydrogels exhibit high potential in the fields of wearable sensors, healthcare monitoring, and e‐skins. However, it remains a huge challenge to integrate high elasticity, low hysteresis, and excellent stretch‐ability in physical crosslinking hydrogels. This study reports the synthesis of polyacrylamide (PAM)‐3‐(trimethoxysilyl) propyl methacrylate‐grafted super arborized silica nanoparticle (TSASN)‐lithium chloride (LiCl) hydrogel sensors with high elasticity, low hysteresis, and excellent electrical conductivity. The introduction of TSASN enhances the mechanical strength and reversible resilience of the PAM‐TSASN‐LiCl hydrogels by chain entanglement and interfacial chemical bonding, and provides stress‐transfer centers for external‐force diffusion. These hydrogels show outstanding mechanical strength (a tensile stress of 80–120 kPa, elongation at break of 900‐1400%, and dissipated energy of 0.8–9.6 kJ m−3), and can withstand multiple mechanical cycles. LiCl addition enables the PAM‐TSASN‐LiCl hydrogels to exhibit excellent electrical properties with an outstanding sensing performance (gauge factor = 4.5), with rapid response (210 ms) within a wide strain‐sensing range (1–800%). These PAM‐TSASN‐LiCl hydrogel sensors can detect various human‐body movements for prolonged durations of time, and generate stable and reliable output signals. The hydrogels fabricated with high stretch‐ability, low hysteresis, and reversible resilience, can be used as flexible wearable sensors. [ABSTRACT FROM AUTHOR]

The surface of low‐dimensional perovskites play a crucial role in determining their intrinsic property. Understanding their characteristics and the influence of certain surfaces is valuable in designing functional surface‐engineered structures. Meanwhile, surface passivation can also be applied to stabilize and optimize the state‐of‐the‐art perovskite‐based optoelectronics. Herein, cesium lead bromide (CsPbBr3) microwire parallel arrays are designed and fabricated with specific (100)‐terminated crystal planes, which exhibit excellent photodetection performance with long‐term environment stability >3000 h. Notably, it is uncovered experimentally and theoretically that environmental oxygen can not only passivate the Br‐vacancy‐related trap states on the (100) surface, but also create charge carrier nanochannels to enhance the (opto)electronic properties. The coupling effects between oxygen species and the specific terminated crystal planes of perovskites highlight the importance of surface engineering for designing and optimizing perovskite‐based devices. [ABSTRACT FROM AUTHOR]

In this study, graphene oxide (GO) and polyacrylamide/polyacrylic acid (PAM/PAA) are used to prepare hydrogels with photothermal conversion properties for highly efficient uranium extraction from seawater. Zwitterionic 2‐methacryloyloxy ethyl phosphorylcholine (MPC) is introduced in the PAM/PAA/GO hydrogel to obtain PAM/PAA/GO/MPC (PAGM), exhibiting good antibacterial properties. PAGM demonstrates efficient and specific adsorption of uranium (VI) (U(VI)). Under light conditions, the adsorption capacity of PAGM reaches 196.12 mg g−1 (pH = 8, t = 600 min, C0 = 99.8 mg L−1, m/v = 0.5 g L−1). The adsorption capacity is only 160.29 mg g−1 under dark conditions (pH = 8, t = 600 min, C0 = 99.8 mg L−1, m/v = 0.5 g L−1). The adsorption capacity of light is 22.5% higher than that of dark. The adsorption process is fitted using the Langmuir and pseudo‐second‐order models. Furthermore, PAGM exhibits good repeatability and stability after five adsorption–desorption cycles. PAGM exhibits a U(VI) adsorption capacity of 6.1 mg g−1 after storage for one month in natural seawater. The X‐ray photoelectron spectroscopy (XPS) results demonstrate that the coordination of the amino, carboxyl, and hydroxyl groups with U(VI) is the primary mechanism of U(VI) adsorption. The mechanism is confirmed through detailed density functional theory calculations. PAGM demonstrates durability, high efficiency, photothermal conversion properties, and antibacterial properties. Thus, it is a promising candidate for uranium extraction from seawater. [ABSTRACT FROM AUTHOR]

Abstract The relationship between the macroscopic non-linear mechanics and the microscopic crystal structural evolution of pre-oriented high-density polyethylene (HDPE) is investigated by in situ synchrotron radiation wide-angle X-ray diffraction (WAXD) measurement over a wide temperature range from −10 to 130 °C. With the concept of stress-induced disordering of crystal, the ratio ( φ a / b ) of lattice parameters a to b is defined as a new structural variable, which can reflect the lattice distortion and then the microscopic stress state of orthorhombic crystal (O-crystal). According to the temperature-dependent non-linear variation of φ a / b with strain, the contributions of O-crystal and monoclinic crystal (M-crystal) to the macroscopic mechanics including linear elasticity, yielding, stress softening and strain hardening are clarified. It is found that M-crystal bears the main extensional stress once formed, although it survives within a limited strain window relying on temperature. By further combining the extensional phase diagram constructed in strain-temperature space, the HDPE deformation is recognized to undergo successively one-dimensional (1D) chain segments rotation of crystal, two-dimensional (2D) crystal plan shearing or slipping and three-dimensional (3D) recrystallization along with increasing strain or stress, demonstrating a multiscale structural transition and energy dissipation mechanism. Graphical abstract Image 1 Highlights • A new structural parameter is defined to characterize the lattice distortion and the microscopic stress state of crystal. • Multiscale structural evolutions of crystal are connected to the macroscopic non-linear mechanics of HDPE under deformation. • The research method can be generalized to other semicrystalline polymers to understand the structure-mechanics relationship. [ABSTRACT FROM AUTHOR]

Abstract Given the advantages of polyethyleneimine (PEI) for interface modification of carbon fiber reinforced polyamide 66 composite (CF/PA66), an effective method was developed to fabricate CNT@PEI-CF. The XPS results confirmed CNT@PEI-CF was covered with a double grafted layer. Interface stability investigated showed thermal stability (under injection molding temperature, about 270 °C) and structural stability of CNT@PEI-CF/PA66 interface were both improved, but PA66 crystallization behavior affected by CNT@PEI-CF was identical with that of pure PA66. The contact angle tests exhibited that its compatibility with PA66 was also enhanced. Its interfacial shear strength, composite tensile strength and elastic modulus increased by 64.74%, 27.58% and 22.68% compared with that of untreated-CFs and composite, respectively. These best mechanical properties were ascribed to the formation of "fish-scale" layers on pull-out fibers resulted from CNT@PEI-CF modification. It could be concluded that CNT@PEI-CF would not only enhance its composite mechanical properties, but also exhibit much fiber pull-out and avoid the catastrophic failure for CNT@PEI-CF/PA66 composites. This CF surface modification study would be beneficial to expand application of thermoplastic composite with reusability. [ABSTRACT FROM AUTHOR]

The operation stability of halide perovskite devices is the critical issue that impedes their commercialization. The main reasons are that the ambient H2O molecules can easily deteriorate the perovskites, while the metal electrodes react in different degrees with the perovskites. Herein, one kind of new electrode, the metalloids, is reported, which are much more stable than the conventional noble metals as electrical contacts for halide perovskites. The degradation mechanism of halide perovskites with noble metal electrodes is carefully studied and compared with the metalloid electrodes. It is found that the iodide ions can easily halogenate Cu and Ag in halide perovskites. Although Au is almost not halogenated, it can also decompose the perovskite film. On the contrary, after long‐term storage, the metalloid electrodes remain intact on the perovskite film without any degradation. In addition, the long‐time operation stability of the perovskite devices with metalloid electrodes is much higher than that of noble metals. First‐principles calculations confirm the exceptional stability of the metalloid electrodes.This work explores the ultra‐stable electrodes for halide perovskites, paving the way to the large‐scale deployment of perovskite‐based electronic devices. [ABSTRACT FROM AUTHOR]

Flexible transparent conductive electrodes (TCEs) that can be used as electromagnetic interference (EMI) shielding materials have a great potential for use as electronic components in optical window and display applications. However, development of TCEs that display high shielding effectiveness (SE) and good stretchability for flexible electronic device applications has proven challenging. Herein, this study describes a stretchable polydimethylsiloxane (PDMS)/silver nanowire (AgNW) TCE with a fence‐like aligned conductive network that is fabricated via pre‐stretching method. The fence‐like AgNW network endowed the PDMS/AgNW film with excellent optoelectronic properties, i.e., low sheet resistance of 7.68 Ω sq−1 at 73.7% optical transmittance, thus causing an effective EMI SE of 32.2 dB at X‐band. More importantly, the fence‐like aligned AgNW conductive network reveals a high stability toward tensile deformation, thus gives the PDMS/AgNW film stretch‐stable conductivity and EMI shielding property in the strain range of 0–100%. Typically, the film can reserve ≈70% or 80% of its initial EMI SE when stretching at 100% strain or stretching/releasing (50% strain) for 128 cycles, respectively. Additionally, the film exhibits a low‐voltage driven and stretchable Joule heating performance. With these overall performances, the PDMS/AgNW film should be well suited for use in flexible and stretchable optical electronic devices. [ABSTRACT FROM AUTHOR]

Hard carbon is one of the most promosing anodes for resource‐rich sodium‐ion batteries. However, an unsatisfactory solid–electrolyte‐interphase formed by irreversible electrolyte consumption caused by defects or oxygen‐containing functional groups of hard carbon impedes its further application. Herein, a novel composite binder that is composed of polar polymer chondroitin sulfate A (sodium salt) and polyethylene oxide by hydrogen bonding demonstrates defect passivation capability. This composite binder can reduce the exposure of defects by forming hydrogen bonds with oxygen functional groups on the hard carbon surface and inhibit the decomposition of electrolyte confirmed by in situ differential electrochemical mass spectrometry. In situ Raman and theoretical calculations reveal that multiple polar functional groups in chondroitin sulfate A (sodium salt) can accelerate the transport of Na+ by adsorbing and facilitate the decomposition of PF6− to form NaF. Additionally, polyethylene oxide in the composite binder can increase viscosity and accelerate the transport of Na+. As a result, an ultra‐thin (9 nm, cyro‐TEM) and NaF‐rich solid–electrolyte interphase is obtained, thereby the hard carbon anode achieves improved initial Coulombic efficiency (84%) and high‐capacity retention of 94% after 150 cycles in a NaPF6/ethylene carbonate/dimethyl carbonate electrolyte. [ABSTRACT FROM AUTHOR]

Recent advances in the cell structure regulation and performances improvement of porous poly(lactic acid) materials (PPMs) are systematically reviewed in this feature article. First, the typical processing methods, including template method, non‐solvent induced phase separation, freeze–drying, and supercritical CO2 foaming, of PPMs are introduced emphatically. Their various cell morphologies by different processing methods are summarized: finger–like, honeycomb–like, fiber–like, through cell, open cell, closed cell, ball–like, and flower–like. Meanwhile, the transformation among different cell morphologies as well as the changes in cell size and cell density, having impact on the performances, is described. Second, the influence of stereo–complex crystals on the cell structure of PPMs is emphatically reviewed. Furthermore, the relationships between cell structure and properties that includes mechanical properties, thermal stability, heat insulation, and hydrophobicity, are elaborated. Eventually, the issues of PPMs worthy of further study are discussed. [ABSTRACT FROM AUTHOR]

Polycarbonate (PC) foam is a versatile material with excellent properties, but its low thermal stability limits its application in high-temperature environments. The aim of this study was to improve the thermal stability of PC foam by adding glass fibers (GF) and to investigate the effect of GF on PC crystallization behavior and PC foam cell morphology. This study was motivated by the need to improve the performance of PC foams in various industries, such as construction, automotive, and medical. To achieve this goal, PC/GF composites were prepared by extrusion, and PC/GF composite foams were produced using a batch foaming process with supercritical carbon dioxide (SC-CO2) as the blowing agent. The results showed that the addition of GF accelerated the SC-CO2-induced crystallization stability of PC and significantly increased the cell density to 4.6 cells/cm3. In addition, the thermal stability of PC/GF foam was improved, with a significant increase in the residual carbon rate at 700 °C and a lower weight loss rate than PC matrix. Overall, this study highlights the potential of GF as a PC foam reinforcement and its effect on thermal and structural properties, providing guidance for industrial production and applications. [ABSTRACT FROM AUTHOR]

Lithium‐ion/sodium‐ion batteries are the most advanced energy storage devices, but the structural evolution of electrode materials, electrolyte decomposition, the growth of Li/Na dendrites and the generation of heat and gas inside batteries represent serious safety issues. Therefore, it is necessary to real time monitor the parameter changes inside these devices. Herein, the recent important progress in a variety of advanced intelligent detection techniques based on the detection of heat, gas, and strain is introduced and discussed. The perfect combination of electrochemical parameters and these advanced intelligent sensing techniques allows the monitoring of the dynamic chemical and thermal evolution during a cell's operation without any impact, which is crucial to making meaningful advancements in energy storage devices. This work provide access to advanced diagnostic tools to guide the rational design of high‐safety batteries. [ABSTRACT FROM AUTHOR]

Electrochemical nitrate reduction to ammonia (eNO3RR) is a green and appealing method for ammonia synthesis, but is hindered by the multistep chemical reaction and competitive hydrogen generation. Herein, the synthesis of 2D SnS nanosheets with tailored interlayer spacing is reported, including both expansion and compression, through the active diatomic Pt‐Ce pairs. Taking together the experimental results, in situ Raman spectra, and DFT calculations, it is found that the compressed interlayer spacing can tune the electron density of localized p‐orbital in Sn into its delocalized states, thus enhancing the chemical affinity towards NO3− and NO2− but inhibiting hydrogen generation simultaneously. This phenomenon significantly facilitates the rate‐determining step (*NO3→*NO2) in eNO3RR, and realizes an excellent Faradaic efficiency (94.12%) and yield rate (0.3056 mmol cm−2 h−1) for NH3 at −0.5 V versus RHE. This work provides a powerful strategy for tailoring flexible interlayer spacing of 2D materials and opens a new avenue for constructing high‐performance catalysts for ammonia synthesis. [ABSTRACT FROM AUTHOR]

The responses of the impact strength and structure of bisphenol A polycarbonate (PC) to aging in a 5 wt% aqueous solution of NaCl were studied in detail. The results of the Izod notched impact test showed that the impact strength decreased from 71.1 kJ/m2 to 17.5 kJ/m2 after an aging time of only 1 day in the aqueous solution of NaCl. The surface appearance of the aged PC observed by polarizing optical microscopy indicated that a large number of microvoids formed, and the size and number of these microvoids increased substantially with an increase in the aging time. The glass transition temperature, measured by differential scanning calorimetry, underwent a slight decrease after aging in the NaCl solution. In addition, no crystallization could be inferred from the heating curves. Thermal gravimetric analysis showed that the thermal decomposition temperature moved to a lower temperature, and the changes of the NaCl solution pH values indicated that hydrolysis was the dominant mechanism of degradation during aging in the aqueous solution of NaCl. Furthermore, the presence of NaCl accelerated the hydrolysis during the early stages of aging. A ductile-brittle transition caused by aging was inferred from observations of fracture surfaces using scanning electron microscopy. [ABSTRACT FROM AUTHOR]

Achieving multifunctionality to broaden the application scenarios is the development direction of electromagnetic wave (EMW) absorbing materials in the future. Here, a waterproof magnetic carbon foam (CF) was successfully prepared using a simple high-temperature pyrolysis and dip coating process, where the magnetic Fe 3 O 4 nanoparticles were homogeneously and tightly encapsulated on the carbon skeleton of CF with the help of low surface energy PDMS, achieving the expected high-efficient EMW absorption performance. Except the 3D porous structure that contributes stronger EMW absorption through multi-reflection and scattering, the coexistence of conductive carbon skeleton and magnetic Fe 3 O 4 can supply the dielectric-magnetic dual-loss, which is also beneficial for better impedance matching. In addition, the amounts of heterointerfaces and abundant crystalline defects and doped N atoms in graphitic carbon can also generate additional polarization loss. Furthermore, high-efficient EMW absorption capacity was achieved by tuning the pyrolysis temperature, of which the CF pyrolyzed at a temperature of 900 °C (PDMS/Fe 3 O 4 /CF-900) exhibited a minimum reflection loss (RL min) value of −47.36 dB with 3.15 mm thickness and a maximum effective absorption bandwidth (EAB max) up to 9.76 GHz with 4.2 mm thickness. What's more, combining with the merits of high conductivity, hydrophobicity, and special 3D porous structure, the expected multifunctionality was also successfully achieved for the prepared PDMS/Fe 3 O 4 /CF-900, where it displays the excellent thermal management performance including a high Joule heating temperature of 161 °C at only 5 V and reliable heating capacity over 1500 s, high-efficient oil-water separation capacity such as high absorption amount (45.58 times), rapid absorption (1.14 s), and stable cyclic adsorption-desorption performances, and great thermal insulation property with a temperature difference up to 219.9 °C that make it to be promising infrared stealth material. This work provides a feasible strategy for the rational design and application of novel lightweight multifunctional high-performance EMW absorbing materials. [Display omitted] • Magnetic carbon foam was prepared for multifunctional EMW absorbing material. • The foam displays a RL min of −47.36 dB and wide EAB of 9.76 GHz. • The foam possesses great potential in the field of personal thermal management. • The foam can be applied for infrared stealth of military equipment. [ABSTRACT FROM AUTHOR]

A combined melt-stretching and quenching setup is designed and developed to allow experimental investigations of polymer crystallization under the complex flow-temperature environments comparable to those encountered in the actual industrial processing. The melt-stretching proceeds by two drums rotating in the opposite directions with simultaneous recording of a stress–strain curve, where the Hencky strain and strain rate (≤233 s−1) are adjustable over a large range. After stretching, liquid N2 is used as a cooling medium to quench the free-standing melt, which is sprayed directly to the deformed melt driven by an electric pump. To ensure a high cooling efficiency, a three-way solenoid valve is employed to execute a sequential control of the liquid N2 flow direction to reduce the boil-off of liquid N2 before entering the sample chamber. The melt cooling rate depends on the liquid N2 flow rate controlled by a flow valve, which is up to 221 °C/s when quenching the isotactic polypropylene (iPP) melt with a thickness of 0.28 mm at 150 °C. Two independent temperature control modules are designed to meet the requirements of different stages of melt-stretching and quenching. To verify the capability of the setup, we have performed the melt-stretching and quenching experiments on iPP samples. The setup is demonstrated to be a valuable new tool to study polymer crystallization under coupled flow-cooling fields. [ABSTRACT FROM AUTHOR]

Passive radiative cooling technology provides a sustainable way of cooling by the combination of emitting heat to the cold universe and reflecting solar light without any energy input. However, the massive consumption of non‐degradable radiative cooling materials causes resource waste and environmental pollution. Meanwhile, the cooling efficiency can be easily affected by dirt contamination in outdoor environments. Here, by the combination of biomimetic hierarchical structure design and stereo‐complex crystals, a degradable and superhydrophobic (152°) stereo‐complex poly (lactic acid) aerogel with low thermal conductivity (37 mW m–1 K–1), high compression strength (0.1 MPa) and self‐cleaning ability via a simple water‐assisted thermally induced phase separation method is developed. The optimal aerogel has a high sunlight reflection (89%) and strong infrared emissivity (93%) that gets a temperature drop of 3.5 °C during the daytime and 5.8 °C during the nighttime. This aerogel opens an environmentally sustainable pathway to radiative cooling applications. [ABSTRACT FROM AUTHOR]

The application of renewable energy conversion devices is considered as one of the effective ways to alleviate the energy shortage and environmental pollution. Designing electrocatalysts with excellent performance and affordable price is promising to accelerate the reaction process and large‐scale application. At present, ruthenium (Ru)‐based nanomaterials have shown similar catalytic activity but superior price demand compared to commercial Pt/C. This undoubtedly makes Ru‐based nanomaterials a perfect candidate to replace advanced Pt catalysts. Significant progress is made in the rational design of Ru‐based electrocatalysts, but an in‐depth understanding of the engineering strategies and induced effects is still at an early stage. This review summarizes the modification strategies for enhancing the catalytic activity of Ru, including surface structure, metal element, nonmetal element, size, bimetallic oxides, and heterostructure engineering strategies. Then the induced electronic modulation effects generated by the intramolecular and intermolecular of the Ru‐based nanomaterials are elucidated. Further, the application progress of engineered Ru‐based nanomaterials for hydrogen and oxygen conversion reactions is highlighted, and the correlations of engineering strategies, catalytic activity, and reaction pathways are elaborated. Finally, challenges and prospects are presented for the future development and practical application of Ru‐based nanomaterials. [ABSTRACT FROM AUTHOR]

In this work, poly(ethylene glycol) (PEG)/boron nitride nanosheets (BNNS) masterbatch was prepared by freeze-drying their ultrasonically homogenized aqueous suspension, followed by melt-mixing with poly(lactic acid) (PLA) to fabricate the nanocomposites. The effect of PEG and BNNS on the crystallization behavior of PLA was investigated. The dynamic mechanical properties, thermal conductivity and thermal stability of the nanocomposites were also evaluated. It was found that, under quiescent conditions, PEG and BNNS had a synergistic effect on accelerating the nonisothermal crystallization of PLA. Unexpectedly, under injection molding conditions, the combination of PEG and BNNS had a negative effect on PLA crystallization. This can be ascribed to the plasticizing effect of PEG, which relaxes the orientation of PLA chains and retards flow-induced crystallization. Dynamic mechanical analysis (DMA) showed that the presence of BNNS enhanced the heat resistance of PLA only when PLA was crystallized, while further incorporation of PEG had a negative effect. Nevertheless, simultaneous use of PEG and BNNS had a synergistic effect on enhancing the thermal conductivity of PLA. [ABSTRACT FROM AUTHOR]

All‐inorganic halide perovskites (AIHPs) are promising photovoltaic materials that have been extensively studied in the last decade. In addition, lead‐free AIHPs are preferred because of their non‐toxic and environmentally friendly nature. However, the quality of AIHPs fabricated by conventional solution processing methods is usually unsatisfactory, which leads to poor photoelectric performance. Herein, a facile polydimethylsiloxane‐assisted slow evaporation method that can be readily used to synthesize high‐quality AIHP microcrystals (MCs) (CsPbBr3, Cs2AgBiBr6, and L‐Cs3Sb2I9) is demonstrated. The photodetection properties of the synthesized AIHP MCs and their spin‐coated thin‐film counterparts are thoroughly studied and compared. Owing to their superior crystallinity, AIHP MCs show better photoelectric performance than spin‐coated films. The responsivity of the CsPbBr3 microcrystal photodetectors is ≈590 000 mA W−1. This work proposes a universal solution‐processing method for the successful fabrication of high‐quality all‐inorganic lead‐based (CsPbBr3), lead‐free (L‐Cs3Sb2I9), and double (Cs2AgBiBr6) perovskites, which can overcome the bottleneck in the development of halide perovskites and promote their applications. [ABSTRACT FROM AUTHOR]