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Ceramic fiber aerogels, a unique feature of mesopores and/or macropores formed by overlapping fibers, are currently one of the most appropriate materials for use in high-temperature thermal insulation. However, they usually exhibit incredibly limited mechanical stability derived from random weak links among ceramic fibers, which can lead to disastrous consequences especially under extreme conditions especially. Here, we report a thermal-insulating silica-based ceramic fiber aerogel with excellent compressive strength, modulus of elasticity, and a very high-temperature resistance limit. A unique feature of the obtained ceramic aerogels is that silica based fibers are connected and welded at their common joints together with remain these abundant multiscale porosities, forming multiple fusing knots in contrast to networks from random placement of weakly connected fibers. Synchronously, under shocks from external forces the introduction of the ZrO2 crystalline phase effectively produces microcrack bifurcations which slow down the crack extension behaviour while maintaining the fracture toughness of the single silica-based ceramic fiber, thereby significantly enhancing the mechanical strength. Consequently, the bulk ceramic aerogels obtained can withstand a maximum elastic strain of more than 80%, and the measured compressive strength is as high as 3.89 × 105 Pa (80% compressive strain). These ceramic aerogels show stable elasticity and structural integrity in an ultra-wide temperature range of -196–1300 °C. Meanwhile, the aerogels have superior mechanical strength, with the energy loss coefficient stabilized at 0.35 after 500 cycles and the lowest thermal conductivity of 0.092 Wm−1 K−1 at 800 oC, which is ahead of most of the ceramic aerogels currently available. This work broadens the application of ceramic aerogels and provides new strategies for their development and design. [ABSTRACT FROM AUTHOR]

The synergization of 3D graphene with magnetic nanoparticles provides effective strategies to shield electromagnetic waves. However, the uniform distribution of magnetic nanoparticles within the 3D graphene network still remains a great challenge, owing to the agglomeration tendency of the magnetic nanoparticles. Herein, we report a facile method to in situ fabricate 3D graphene decorated with highly dispersed nickel nanoparticles (Ni NPs) by laser conversion from the polyimide/Ni(II) precursor film. In this process, 3D graphene was generated by CO2 laser scribing of the polyimide film, accompanied by carbothermal reduction of Ni(II) to form Ni NPs. Significantly, in the precursor film, carboxylate ions were introduced to complex with Ni(II), leading to a uniform dispersion of Ni(II), thus Ni NPs with high dispersibility in 3D graphene networks were achieved after laser fabrication. As a result, massive heterogeneous interfaces and dense magnetic coupling networks were realized in the graphene/Ni composite, which is conducive to improving polarization loss and magnetic loss for the dissipation of incident electromagnetic waves. Combined with the multiple electromagnetic wave dissipation paths provided by 3D graphene, the graphene/Ni composite exhibits absorption-dominated electromagnetic interference shielding effectiveness (EMI SE). At an Ni content of 5.3 wt%, the EMI SE of the double-layer graphene/Ni composite was 94 dB with an adsorption ratio of 91% in the X-band. Such a high EMI SE value will pave the way for practical applications of 3D graphene in EMI shielding. [ABSTRACT FROM AUTHOR]

The plasmonic photothermal conversion efficiency can be enhanced by coupling among plasmonic atoms or plasmonic molecules due to the amplified local electric field and extinction cross-section. Recently, it has been theoretically proved that hybridization between dipolar modes and higher order modes can provide higher enhancement than that among dipolar modes in terms of both near- and far-field, which may lead to a higher photothermal conversion rate. In this work, we systematically investigated the photothermal conversion enhancement of plasmonic coupling between a dipolar mode of a titanium nitride nanoparticle (TiN NP) and a higher order mode of a gold nanorod (Au NR), which was compared to that of coupling among TiN NPs' dipolar modes. We evaluated the photothermal conversion efficiency of dipole–dipole coupling and dipole–multipole coupling in the nanocluster under the illumination of a monochromatic laser of 808 nm wavelength and simulated solar light, respectively. Both experimental tests and numerical simulations suggested that the plasmonic dipole–multipole coupling exhibited higher enhancement in photothermal conversion than dipole–dipole plasmonic coupling. [ABSTRACT FROM AUTHOR]

Considering the continuous development of electronic equipment superintegration and miniaturization, difunctional materials that have both effective heat management and electromagnetic interference (EMI) shielding performance are urgently required. Herein, sandwich-type phase change composites (STPCCs) with efficient heat management and temperature-regulated electromagnetic interference shielding performance were designed and prepared through an easy pressing process, in which an expanded graphite (EG)/multi-walled carbon nanotube (MWCNT) hybrid porous scaffold adsorbed the phase-change material eicosane (ES) was the middle layer, and polyvinylidene fluoride/ferric oxide (PVDF/Fe3O4) magnetic spinning films were the top and bottom layers. Due to the multiple synergistic effects among the sandwich structure, carbon materials, Fe3O4 and ES, the resulting STPCCs displayed high volume conductivity (135 S cm−1) and excellent EMI shielding effectiveness (EMI SE) (98.4 dB). Impressively, above the phase transition temperature of ES, the volume electrical conductivity of STPCCs increased to 146.2 S cm−1, their EMI SE increased to 115.75 dB, and their absorption shielding accounted for 85.2% of the total shielding in the X-band, significantly showing a temperature-regulated EMI shielding performance and outperforming most of the reported the synthetic equivalents. In addition, the obtained STPCCs exhibited excellent thermal conductivity (3.61 W m−1 K−1), exhibiting more effective heat dissipation ability in advanced electronic devices. [ABSTRACT FROM AUTHOR]

Heteroatom doping of graphene electrodes is a valid strategy to enhance their capacitive performance. This work demonstrates a facile and expandable methodology for the in situ fabrication of nitrogen-doped laser-induced graphene (N-LIG) by the precursor composite approach in conjunction with laser induction technology. Melamine (C3H6N6) with high N content was compounded with polyimide to form a composite film, on which N-LIG was synthesized by one-step in situ laser pyrolysis. In this process, N elements from melamine were successfully doped into the graphene structure. As a result, the optimal N-LIG electrode exhibited a desirable specific areal capacitance (CA) of 56.3 mF cm−2 at 0.4 mA cm−2 in 1 M H2SO4 aqueous electrolyte, which was 7.2 times that of the pristine undoped LIG electrode. Besides, the N-LIG electrode obtained on the composite film kept good flexibility, which laid a foundation for the industrial roll to roll production of N-LIG. Furthermore, the N-LIG-based all-solid-state micro-supercapacitor (MSC) revealed a high CA of up to 35.20 mF cm−2 at 0.05 mA cm−2 and an impressive cyclic stability of 85.5% after 10 000 cycles. This presented strategy possesses the advantages of environmental protection, economy and convenience, and exhibits a broad application prospect in flexible wearable electronics and energy storage devices. [ABSTRACT FROM AUTHOR]

Enhancing the energy storage capacity of supercapacitors is facing great challenges. Converting solar energy into heat energy has emerged as a promising strategy to enhance the capacity of energy storage devices by elevating their working temperature, especially under low-temperature conditions. Unlike traditional energy storage devices, higher requirements are put forward for the cycle stability of solar thermal device electrodes. Herein, a novel light-absorbing structure of supercapacitor electrodes composed of 3D porous graphene and polypyrrole is established. The uniform composite structure and matching thermal expansion properties of the composite electrode endows the fabricated solar-thermal micro-supercapacitor (ST-MSC) with superior capacitance and cycling stability. Under one solar irradiation, the temperature of the ST-MSC increases to 60 °C, leading to a 4.8-fold increase in the specific capacitance and energy density (up to 2754 mF cm−2 and 646.6 µW h cm−2, respectively); the ST-MSC exhibits excellent cycle stability with 85.8% capacitance retention after 10 000 cycles, which is much better than most of the reported ST-MSCs. Moreover, at a low temperature of −30 °C, the severely attenuated capacitance performance of the ST-MSC is greatly improved under one solar irradiation to a level close to that at room temperature. This work provides a new strategy for designing solar thermal electrodes and their derived high-performance energy storage devices. [ABSTRACT FROM AUTHOR]

Pore-forming toxins (PFTs), the most common virulence proteins, are promising therapeutic keys in bacterial infections. CAL02, consisting of sphingomyelin (Sm) and containing a maximum ratio of cholesterol (Ch), has been applied to sequester PFTs. However, Sm, a saturated phospholipid, leads to structural rigidity of the liposome, which does not benefit PFT combination. Therefore, in order to decrease the membrane rigidity and improve the fluidity of liposomes, we have introduced an unsaturated phospholipid, phosphatidylcholine (Pc), to the saturated Sm. In this report, a soft nanoliposome (called CSPL), composed of Ch, Sm and Pc, was artificially prepared. In order to further improve its antibacterial effect, vancomycin (Van) was loaded into the hydrophilic core of CSPL, where Van can be released radically at the infectious site through transmembrane pores formed by the PFTs in CSPL. This soft Van@CSPL nanoliposome with detoxification/drug release was able to inhibit the possibility of antibiotic resistance and could play a better role in treating severe invasive infections in mice. [ABSTRACT FROM AUTHOR]

Thermal interface materials (TIMs) have become more and more necessary in miniaturized modern devices, so the exploration of highly thermally conductive TIMs with flexibility and elasticity are of great significance. Herein, a polymer-based thermoplastic polyurethane (TPU) composite membrane with high thermal conductivity, flexibility and elasticity was conveniently prepared via constructing thermal conduction channels of ultra-thin hexagonal boron nitride nanosheets (h-BNNSs) and carbon nanotubes (CNTs). Then the maximum thermal conductivity of h-BNNSs/CNTs/TPU composite is up to 1.35 W m−1 K−1, increasing thermal conductivity of original polymer TPU by about 513%. The excellent thermal conductivity is attributed to the construction of the multi-channel heat transfer structure among the ultra-thin h-BNNSs with good in-plane thermal conductivity and CNTs. Moreover, the composite membrane has fantastic insulation and it can be stretched to at least 300% of its original length. Therefore, the fabricated h-BNNSs/CNTs/TPU composite membrane has great potential as important TIMs in thermally conductive applications. [ABSTRACT FROM AUTHOR]

The hydrogen evolution reaction (HER) is an important step for electrochemical water splitting to produce hydrogen. Functional materials with low cost and robust performance might meet the urgent need for replacement of Pt-based electrocatalysts for the HER. Herein, a simple one-pot method is designed to prepare metal–organic framework (MOF)-derived PdNiCo alloys encapsulated in a nitrogen-doped graphene shell for efficient hydrogen evolution reactions. The electrocatalyst demonstrated an outstanding performance with only 42 mV overpotential to achieve 10 mA cm−2 current density, quite close to that of the commercial 20% Pt/C catalyst. Moreover, the underlying reason for the outstanding performance is that introduction of trace palladium atoms into the core can improve the efficiency of electron transfer from the alloy core to the graphene shell, and the PdNiCo alloy/nitrogen-doped carbon interfaces weaken the hydrogen adsorption energy on the catalyst and thus optimize the Gibbs free energy of the intermediate state (ΔGH*), leading to a remarkable electrocatalytic activity. These results indicate that robust and super stable alloys encapsulated in nitrogen-doped graphene containing a very small amount of noble metal could effectively improve the electrocatalytic performance. This work gives new insights into the investigation of efficient and practical multilayer core–shell structured HER catalysts. [ABSTRACT FROM AUTHOR]

The micro/nanostructure of electrode materials is one of the key factors affecting the performance of supercapacitors. Here, a hybrid electrode composed of nickel–cobalt layered double hydroxide (NC-LDH) nanosheets supported on vertical graphene fibers was designed for flexible supercapacitors. An efficient and low-cost laser-induced technology was explored to synthesize vertical graphene fibers using polyphenylene sulfide (PPS) as a precursor. By double laser writing in two directions perpendicular to each other, laser-induced graphene (LIG) fibers with improved conductivity and optimized morphology were achieved. As a result, porous NC-LDH nanosheets with high specific capacitance can be uniformly loaded onto LIG fibers by the electrodeposition method. The as-obtained composite with fast electron transfer and efficient ion transport properties was used as a supercapacitor electrode, achieving an ultrahigh specific capacitance of 4503 mF cm−2 at 1.0 mA cm−2 in a standard three-electrode system. Furthermore, a flexible asymmetric supercapacitor (ASC) was successfully assembled using NC-LDH/LIG as the positive electrode and activated carbon as the negative electrode with the PVA–KOH gel electrolyte, obtaining a high energy density of 219 μW h cm−2 at a power density of 378 μW cm−2. These excellent electrochemical properties are attributed to the rational structural design of the electrode and the synergistic effect of each electrode component, which exhibits great application prospects in flexible energy storage devices. [ABSTRACT FROM AUTHOR]

The phase transition process from VO2(B) to VO2(A) was first observed through a mild hydrothermal approach, using hybrid density functional theory (DFT) calculations and crystallographic VO2topology analysis. All theoretical analyses reveal that VO2(A) is a thermodynamically stable phase and has a lower formation energy compared with the metastable VO2(B). For the first time, X-ray absorption spectroscopy (XAS) of the V L-edge and O K-edge was performed on different VO2phases, and the differences in the electronic structure of the two polymorphic forms provide further experimental evidence of the more stable VO2(A). Consequently, transformation from VO2(B) to VO2(A) is much easier to be realized from a dynamical point of view. Notably, the transformation of VO2(B) into VO2(A) show the sequence VO2(B)-high-temperature VO2(AH) phase-low-temperature VO2(A) phase, which was achieved by hydrothermal treatment, respectively. Also, an alternative synthesis route was proposed based on the above hydrothermal transformation, and VO2(A) was successfully prepared viathe simple one-step hydrothermal method by hydrolysis of VO(acac)2(acac = acetylacetonate). Therefore, VO2nanostructures with controlled phase compositions can be obtained in high yields. Through elucidating the structural evolution in the crystallographic shear mechanism, we can easily guide the design of other metal oxide nanostructures with controllable phases. [ABSTRACT FROM AUTHOR]

In this article, we have demonstrated top-down solid-phase transformation from calcium oxalate dehydrate (COD) tetragonal prisms into highly macroscaled mesoporous calcium carbonate tetragonal prisms. Also, being a promising C2O42−source, l-ascorbic acid (AA) was first applied to obtain high-quality COD tetragonal prisms. The high crystal quality of COD is critical for the successful fabrication of porous CaCO3microcrystals with predetermined morphology and well-controlled internal structure. Calcined at different heating rates, porous CaCO3with different pore sizes was obtained. This novel, simple thermal transformation strategy is convenient for preparing nanoporous materials at a large scale, and it is also useful to further extend to convert salt carbonate into such porous nanostructures. The as-obtained porous CaCO3tetragonal prisms are nontoxic, cheap and environmentally friendly, and the application of such porous CaCO3with different pore sizes as support matrices successfully mitigates the common problems for phase-change materials (PCMs) of inorganic salts, such as phase separation phenomena and super-cooling effect. Our experiments clearly reveal that the confinement effect of the porous structure plays a more dominant role in mitigation of the phase separation while the mesoporous CaCO3microcrystals with the smaller mesopore sizes used PCMs as supporters. However, heterogeneous nucleation will be responsible for the mitigation of the phase separation in the macroporous CaCO3support matrix, while in this case, size confinement effect is negligible. Thereby, the designed porous nanostructures can bring significant improvements to the heat-storage performance in future “smart house” wall materials. [ABSTRACT FROM AUTHOR]

A novel multiresponsive function of monoclinic BiVO4has been put forward for the first time, and loosely packed monoclinic BiVO4nanoellipsoids with many exposed crystal planes have been designed and synthesized in order to improve their smart multiresponses to visible light, trace gas and temperature. [ABSTRACT FROM AUTHOR]

Anti-/de-icing of glass surfaces is of great importance in present daily life. The long-standing challenge in this field is largely due to the lack of stable multifunctional coatings that can be conveniently and economically constructed on the glass surface, and more importantly, are capable of retaining the original transparency of glass ranging from the visible to the near infrared spectrum. Herein, a direct spraying sol method on the glass surface to prepare a highly transparent and photothermal composite coating is reported. Such multifunctional coating of Cu 7 S 4 nanoparticles/organo-silicone sols has displayed a good photothermal conversion property and hydrophobic property and therefore yields excellent anti-icing and self-melting ice properties. The condensation time of water droplets can be extended to 86 s even at -10 °C, which is 3.42 times delayed relative to ordinary blank glass. And the adhesion strength of ice is largely reduced to 72 KPa, which is as low as ∼1/3 that of ordinary glass. Meanwhile, the subcooling of adhering droplets is reduced to -12 °C under one solar illumination condition and exhibits a rapid de-icing capability. More impressively, the prepared functional coating glass shows an outstanding transmittance of more than 75% in the visible region, while it is over the minimum glass transmittance limit allowed by Safety Standards for Glass (GB9656-2016, China). In addition, the multifunctional photothermal glass coating exhibits good physical/chemical stability, which facilitates the long-term application of the coating in different environments., Competing Interests: There are no conflicts to declare., (This journal is © The Royal Society of Chemistry.)

In recent years, liquid biopsies, especially for detecting circulating tumor cells (CTCs), have received great attention for cancer diagnosis and treatment monitoring. For clinical diagnosis of prostate cancer (PCa), prostate specific antigen (PSA) has been widely used as a standard method for PCa screening. However, PSA diagnostic efficacy within early-stage PCa patients with a PSA level of 4-10 ng mL -1 is always controversial. Therefore, the development of new methods to assist clinical PSA diagnosis is greatly desired. Herein, we report the fabrication of antibody-modified reduced graphene oxide films, which can be used to efficiently detect CTCs in PCa patients with PSA levels of 4-10 ng mL -1 . The antibody-modified reduced graphene oxide (rGO) films were fabricated by spray coating reduced graphene oxide solution onto a smooth glass slide and then modifying it with anti-epithelial cell adhesion molecules (anti-EpCAMs) and anti-prostate specific membrane antigen (anti-PSMA). The rGO films exhibited an excellent ability to capture CTCs from the blood of PCa patients with PSA levels of 4-10 ng mL -1 and the efficiency could reach 60% (6/10). Our approach for highly efficient detection of CTCs in early-stage PCa patients may provide great potential in assisting clinical cancer diagnosis., Competing Interests: There are no conflicts to declare., (This journal is © The Royal Society of Chemistry.)

The phase transition process from VO(2) (B) to VO(2) (A) was first observed through a mild hydrothermal approach, using hybrid density functional theory (DFT) calculations and crystallographic VO(2) topology analysis. All theoretical analyses reveal that VO(2) (A) is a thermodynamically stable phase and has a lower formation energy compared with the metastable VO(2) (B). For the first time, X-ray absorption spectroscopy (XAS) of the V L-edge and O K-edge was performed on different VO(2) phases, and the differences in the electronic structure of the two polymorphic forms provide further experimental evidence of the more stable VO(2) (A). Consequently, transformation from VO(2) (B) to VO(2) (A) is much easier to be realized from a dynamical point of view. Notably, the transformation of VO(2) (B) into VO(2) (A) show the sequence VO(2) (B)-high-temperature VO(2) (A(H)) phase-low-temperature VO(2) (A) phase, which was achieved by hydrothermal treatment, respectively. Also, an alternative synthesis route was proposed based on the above hydrothermal transformation, and VO(2) (A) was successfully prepared via the simple one-step hydrothermal method by hydrolysis of VO(acac)(2) (acac = acetylacetonate). Therefore, VO(2) nanostructures with controlled phase compositions can be obtained in high yields. Through elucidating the structural evolution in the crystallographic shear mechanism, we can easily guide the design of other metal oxide nanostructures with controllable phases.

A novel multiresponsive function of monoclinic BiVO(4) has been put forward for the first time, and loosely packed monoclinic BiVO(4) nanoellipsoids with many exposed crystal planes have been designed and synthesized in order to improve their smart multiresponses to visible light, trace gas and temperature.