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The universal remote sensing image processing software focuses on the preprocessing of remote sensing data, and it is used to implement the monitoring and evaluation functions of the ecological environment such as drought and flood. The operation is complex. In order to simplify the work process of natural geographical environment monitoring and assessment, GIS technology and data mining technology were combined in this paper. With monitoring and evaluation as the core, a decision tree model was constructed. Taking the Dongting Lake as an example, the scale and characteristics of its texture were studied, and combined with other ancillary data, the Dongting land information was explored and the land types were classified. Finally, a conclusion was reached: The algorithm designed in this paper can be applied to the land types of the natural geographical environment. The classification model has a positive guiding role in the judgment of environmental monitoring and assessment. [ABSTRACT FROM AUTHOR]

The ability to control the assembly of micro/nanosized particles at liquid-liquid interface with external inputs promises new opportunities in nanofabrication and biomedicines. This work aims to demonstrate a way to control of dynamic assembly of nanoparticles at liquid-liquid interface by light and magnetic field, which consequently enables the formation of dynamic emulsion droplets. Magnetic Fe 3 O 4 nanoparticles functionalized with azobenzene moieties (Fe 3 O 4 @AZO) were synthesized and were dispersed in toluene/(N, N -dimethylformamide, DMF) binary solvent. After irradiation with UV or visible light, the assembly behavior of these Fe 3 O 4 nanoparticles were evaluated by electron microscopy and fluorescent microscopy. Under UV light, Fe 3 O 4 @AZO nanoparticles were self-assembled due to the increase of dipolar interaction from the photoisomerization of azobenzene and polar molecules, DMF, were harvested from a binary solvent of DMF/toluene. While under visible light, a relief of dipolar interactions between Fe 3 O 4 @AZO nanoparticles can induce the secondary assembly of these Fe 3 O 4 @AZO nanoparticles at DMF-toluene interface, resulting in DMF droplets covered by a layer of nanoparticle superlattices. More importantly, coupled with a magnetic field, these emulsion droplets can be shaped into one dimensional ones during the interfacial assembly process, thereby giving rise to dynamic emulsions controlled by light and magnetic field. [ABSTRACT FROM AUTHOR]

The different atomic ratios of FeCo alloys with various morphologies have been prepared through a simple liquid-thermal reduction method. It is found that the atomic ratio of ferrum and cobalt has great influence on the formation of FeCo alloys. Via adjusting Fe/Co atomic ratio (3:7, 5:5, 7:3), the surface of alloy becomes smooth gradually from distinct cone structure, and the saturation of alloys have been improved with the increase of Fe proportion. The impedance matching is also related tightly with atomic ratio and the best condition can be achieved by Fe 7 Co 3 with lower dielectric constant and higher permeability. It is delighted to find that the optimal reflection loss (RL) value of Fe 7 Co 3 can reach −53.6 dB at 14.3 GHz with a thin thickness of 1.55 mm and the RL values less than −10 dB can be gained from 11.2 to 18 GHz, which covering the whole Ku-band. The excellent performance derived from strong magnetic loss and well dielectric loss guarantees it as an ideal high-frequency microwave absorbent. [ABSTRACT FROM AUTHOR]

An ultrafacile aluminum reduction method is reported herein for the preparation of blue TiO2 nanoparticles (donated as Al-TiO2, anatase phase) with abundant oxygen deficiency for lithium-ion batteries. Under aluminum reduction, the morphology of the TiO2 nanosheets changes from well-defined rectangular into uniform round or oval nanoparticles and the particle size also decreases from 60 to 31 nm, which can aggressively accelerate the lithium-ion diffusion. Electron paramagnetic resonance (EPR) and positron annihilation lifetime spectroscopy (PALS) results reveal that plentiful oxygen deficiencies relative to the Ti3+ species were generated in blue Al-TiO2; this effectively enhances the electron conductivity of the TiO2. X-ray photoelectron spectrometry (XPS) analysis indicates that a small peak is observed for the AlO bond, which probably plays a very important role in the stabilization of the oxygen deficiencies/Ti3+ species. As a result, the blue Al-TiO2 possesses significantly higher capacity, better rate performance, and a longer cycle life than the white pure TiO2. Such improvements can be attributed to the decreased particle size, as well as the existence of the oxygen deficiencies/Ti3+ species. [ABSTRACT FROM AUTHOR]

The pencil-like ZnO hollow tubes with 9–12 μm in length, 350–700 nm in width, 200 nm in wall thickness coating with g-C 3 N 4 have been prepared via a chemical deposition process. As compared with uncoated ZnO or g-C 3 N 4 , these g-C 3 N 4 /ZnO composites showed the enhanced photocatalytic activity which can be attributed to the heterojunction structure. Furthermore, it is worth pointing out that the weight ratios of g-C 3 N 4 to ZnO (g-C 3 N 4 /ZnO) played a significantly influence on the photodegradable properties. With increasing the mass ratio, the photocatalytic activity increased firstly and then decreased after reaching to an optimal photocatalytic performance. It can be inferred that the appreciation of g-C 3 N 4 on the ZnO surface can improve the contact area which resulted in high separation of electrons and holes. However, excessive g-C 3 N 4 may hinder the electrons transferring from the g-C 3 N 4 to ZnO, and thus worse its photocatalytic performance. In our study, the g-C 3 N 4 /ZnO sample prepared with 10 wt% of g-C 3 N 4 exhibited the optimal photodegradable efficiency which 94% of Rhodamine B (RhB) has been degraded just in 2 h. [ABSTRACT FROM AUTHOR]

The binary composites of conducting polyaniline (PANI) and nickle zinc ferrite were synthesized by an in-situ polymerization process, and the electromagnetic absorption properties of the composites were also investigated. The FT-IR spectra present the peaks of PANI (1562, 1481, 1301, 1109, and 799 cm −1 ) and the bonds of NiZn ferrite (579 and 390 cm −1 ), indicating the existence of both NiZn ferrite particles and PANI in the composites. With the increasing ratio of nickle zinc ferrite, the composites distributes in irregular compared with pure PANI and Ni 0.6 Zn 0.4 Fe 2 O 4 . The TG curves of the pure PANI and PANI/Ni 0.6 Zn 0.4 Fe 2 O 4 composites with different molar ratios clearly show the increase percentage of the ferrite in the composites. Furthermore, we found that the excellent electromagnetic absorption properties and wide absorption bandwidth can be achieved by adjusting proper molar ratios Ni 0.6 Zn 0.4 Fe 2 O 4 to PANI. The maximum reflection loss of Ni 0.6 Zn 0.4 Fe 2 O 4 /PANI can reach to −41 dB at 12.8 GHz and the bandwidth exceeding −10 dB can reach to 5 GHz with the absorber thickness of 2.6 mm at the molar ratio of 1:2. This can be attributed to the enhancing magnetic loss and the better impedance matching. Therefore, Ni 0.6 Zn 0.4 Fe 2 O 4 /PANI ferrite composites can become a new kind of candidate in the field of the microwave absorbing. [ABSTRACT FROM AUTHOR]

In this work, a simple two-step ball-milling method has been applied to prepare the flake-like FeAl mixture. The mixing ball-milling time is considered to significantly influence the magnetic properties. With the rising of the mixing ball-milling time, the saturation magnetization values decreased first and then increased after reaching to the lowest M s value. On the other hand, the mixing ball-milling process also created a remarkably effect on the microwave absorbing and infrared emission properties. It is surprisingly to find that the mixture prepared by 30 min of mixing ball-milling presented the best radar-infrared compatible properties, the minimum reflection loss is about −13.1 dB and the lowest infrared emission is only around 0.1. [ABSTRACT FROM AUTHOR]

A simple liquid phase reduction method has been developed for the preparation of hexagonal-cone like Fe 50 Co 50 alloy with particle size of 300–400 nm. The ultrasonic irradiation time during the reaction is considered to remarkably influence the formation of hexagonal-cone like Fe 50 Co 50 alloy. With the rising of ultrasonic irradiation time, it is clearly seen that the cubic-like of FeCo appeared firstly and then evolved into triangular pyramidal, and finally converted to hexagonal cone when FeCo grows on the middle line of three triangular′s face. On the other hand, the time of ultrasonic irradiation also played a significantly role in the magnetic and microwave absorbing properties. With increasing the ultrasonic time, the value of the saturation magnetization ( Ms ) increased firstly at the first stage and then decreased after reaching to the optimal Ms value. It is surprisingly to find that the sample prepared through 3 h ultrasonic treatment, exhibited the highest Ms of 225 emu/g and the ideal reflection loss of −22 dB with 7.1 GHz frequency width (below −10 dB). [ABSTRACT FROM AUTHOR]

Abstract: Fe/Cu composite samples with Cu particles depositing on carbonyl iron sheets were prepared by chemical plating. Cu additions were uniformly distributed on the grain boundaries of the flaky carbonyl iron while keeping the internal structure of iron. Meanwhile, we found that the chemical plating time made a key point on both the microwave absorbing properties and infrared emissivity. With the growth of chemical plating time, the value of reflection loss gives a linear decrease and the infrared emissivity is reduced with a tendency of index reduction. When the plating time is less than 30min, the reflection loss of the samples maintains above −20GHz, moreover, prolonging the plating time more than 30min, the infrared emissivity of the samples is reduced to 0.50 or less. It can be concluded that both the microwave absorbing and infrared properties are excellent at the optimal plating time of 30min. [Copyright &y& Elsevier]

Abstract: Cu2O/TiO2 composite nanotube arrays demonstrating enhanced photocatalytic performance were synthesized using an electrodeposition method to impregnate the p-type Cu2O into the n-type titanium dioxide nanotube arrays (TNTs). The morphological results confirmed that the TNTs are wrapped by the Cu2O nanoparticles and the UV–Vis absorption spectra showed that the Cu2O/TNTs display a better ability for visible light absorption compared to the pure TNTs. CO2 photocatalytic reduction experiments carried out by using Cu2O/TNT nanocomposites proved that Cu2O/TNTs exhibit high photocatalytic activity in conversion of CO2 to methanol, while pure TNT arrays were almost inactive. Furthermore, Cu2O/TNTs also exhibited augmented activity in degradation of target organic pollutant like acid orange (AO) under visible light irradiation. The ultra enhanced photocatalytic activity noticed by using Cu2O/TNTs in CO2 reduction and degradation of organic pollutant could be attributed to the formation of Cu2O/TiO2 heterostructures with higher charge separation efficiency. [Copyright &y& Elsevier]

Uniform well-crystallized flower-like BiOI nanoplates contained 3.7 nm mesopores, which may be attributed to the internanosheet spaces of BiOI with maximum pore diameters of about 30 nm, were successfully synthesized via a simple ethylene glycol-assisted solvothermal method. The as-prepared porous BiOI nanoplates exhibited excellent adsorption ability, and the saturated extent of adsorption of BiOI over an RhB solution was as high as 197 mg/g, which is much higher than those for BiOCl and BiOBr prepared via the same method and with a similar surface area. The probable adsorption mechanism could have originated from the interaction between the I atom in BiOI and a proton in RhB at different pH values and temperatures. With visible light irradiation ( λ > 420 nm), 80 % of the RhB was degraded in 4 h, while BiOI still demonstrated reasonably outstanding photocatalytic ability under green light ( λ = 550 ± 15 nm) because of its low-energy gap (1.72 eV). The degradation test for BiOI under irradiation at λ = 550 ± 15 nm is an excellent achievement for field applications because the catalyst can be applied in solar irradiation to remove organic pollutants, which may be of great value BiOI complex. [ABSTRACT FROM AUTHOR]

Abstract: Uniform well crystallized flower-like three-dimensional (3D) BiOClBr and I-doped BiOClBr microspheres with diameter of 1μm were synthesized through a simple EG-assisted solvothermal method. The existence of I atoms in the BiOClBr compound could greatly enhance both adsorption and photocatalytic activity as compared with the BiOClBr and BiOX (Cl, Br, I) monomers. The highest catalytic performance of the flower-like 3D I-doped BiOClBr microspheres was preliminary deduced to be due to the much higher specific surface area, efficient sorption capacity as well as the unique interfacial structure. These factors may favor the absorption of light and separation of photogenerated charged carriers more effectively. [Copyright &y& Elsevier]

Abstract: Magnetic Co–Cu alloy nanowires with low Cu content were prepared by SC electrodeposition in pores of anodic aluminum oxide templates. The as-deposited Co–Cu nanowires, with a diameter of 15nm, show distinctive magnetic anisotropy as an applied magnetic field parallel to the axis of nanowires. With increase in the molar ratio of Co and Cu, the coercivity along nanowire axis increases and reaches a maximum value of 1977.5Oe at the Co/Cu molar ratio of 60:1, but the maximum value of coercivity increases to 1743.6Oe with the decrease of frequency to 2Hz. [Copyright &y& Elsevier]

Abstract: Ultrafine nanowires of Fe–Co with a diameter around 15nm have been fabricated by electrodeposition method using anodic porous alumina as a template. The alloy nanowires were in the form of arrays and consisting of polycrystalline structures. They showed obvious shape anisotropy parallel to the axis of nanowires and the perpendicular coercivity (Hc⊥) was found to be 2576.8Oe which is higher than any coercivity value reported in the literature. The effects of critical factors such as heat treatment and temperature of annealing on the structure and magnetic properties of the ultrafine nanowire arrays were studied and discussed. [Copyright &y& Elsevier]

Abstract: Arrays of cobalt nanorods consisting of a number of nanowires have been fabricated by the electrochemical method using an anodic-aluminum oxide (AAO)/mesoporous-silica (SBA-15) composite. Microscopic studies clearly display that each nanorod (with a diameter of ∼200 nm) of the array was consisting of a number of cobalt nanowires which exhibit an average diameter of 3 nm. The observed hysteresis loops measured at room temperature indicate that the magnetic shape anisotropy of cobalt mesostructures, i.e. the parallel and perpendicular squarenesses of 0.5 and 0.1, respectively have been estimated. The maximum value of the coercivity measured perpendicular to the sample axis shows a value of 330 Oe and it was found that the coercivity decreases by increasing the temperature which is possibly caused by thermal disturbance inside the arrays. [Copyright &y& Elsevier]

Abstract: Bi2Te3 crystals with plate-like morphology have been successfully synthesized via a microwave-assisted heating approach in room temperature ionic liquid (RTIL) of 1-butyl-3-methylimidazolium bromide (C8H15BrN2). Scanning electronic microscopy (SEM) observation of as-synthesized Bi2Te3 confirmed their morphology of the hexagonal plates. It was observed that the edge and thickness values of as-synthesized Bi2Te3 were in the size of 0.5–2μm and less than 100nm, respectively. High-resolution transmission electronic microscopy (HR-TEM) and selected area electron diffraction (SAED) results revealed that the Bi2Te3 plates are of single-crystal in nature with the growth direction of . In addition, as increasing the amount of ionic liquid, SEM results showed a novel evolution process of Bi2Te3 morphologies from mixture of Bi2Te3 nanorods and nanoplates to regular hexagonal plates, and then nanoplates with many small flecks. Furthermore, a possible mechanism regarding the formation of Bi2Te3 plates was proposed as well on the basis of the experimental results. The power factor of Bi2Te3 nanoplates is examined to evaluate its thermoelectric property. [Copyright &y& Elsevier]

Abstract: Cu2O nanowires were successfully fabricated by a simple liquid reaction in the presence of amphiphilic triblock copolymer (P123). The concentration of copolymer and aging time drastically changed the morphology of Cu2O samples. XPS results show that tiny amount of CuO as well as some absorbed O2 molecules existed on the surface of the Cu2O nanowires. Thermal analysis shows that the triblock copolymer owns a higher decomposition temperature (∼645°C) than that of pervious research results and this may be the result of strong interaction between P123 and Cu2O. The band gap of Cu2O nanowires was estimated about 2.23eV and shifting of the band gap with decreasing of the particle size could also be found. The photoluminance property study reveals that the intrinsic emission peak of Cu2O nanowires can be observed at 546nm under the excitation wavelength of 400nm (Xe lamp was used as the excitation light source). [Copyright &y& Elsevier]

The photocatalytic performance of sodium pentachlorophenate (PCP¿Na) over NaBiO3 under visible light irradiation was first investigated systematically. After 1h of photocatalytic reaction, the degradation rate of PCP¿Na could reach to 90.5% in appropriate conditions. dominant photooxidant rather than O2 ¿ based on the experiment results and density of states (DOS) analysis. The PCP¿Na solution became basic (pH value increased to ¿9) with the progress of photocatalytic reaction which may be attributed to the PCP¿ oxidized to the pentachlorophenoxy radical by an attack on PCP¿ by hotocatalyic reaction over NaBiO3 follows the rule of first-order reaction according to the Langmuir¿Hinshelwood model. The initial concentration of the PCP¿Na, the initial pH value of PCP¿Na aqueous solution and the amount of NaBiO3 used have great influences on the photocatalytic performance. Three kinds of photocatalytic systems (P25, Bi2O3 and P25¿Bi2O3 heterojunction) exhibited relative lower photocatalytic activity compared to NaBiO3 powder. [Copyright &y& Elsevier]

Abstract: High-density Co3O4 nanowire arrays have been fabricated by a simple, solvent-free synthesis method inside the alumina pores. It has been found that the pore diameter played a key role in the formation of the Co3O4 nanowires. When the same reaction was performed in the narrow pores of the AAO template (<90nm), a mixture of nanoparticles and short nanorods were obtained. The nanorod consists of a lot of obvious grains, which form grain chains. However, continuous and uniform nanowires could be produced when the larger pores of AAO (>120nm) were applied. Selected-area electron diffraction (SAED) patterns revealed that the nanowires were single-crystalline. Electrochemical measurements by an electrochemical workstation indicate that the specific capacitance characteristics of the as-prepared Co3O4 nanowires are much higher than that of Co3O4 particles. [Copyright &y& Elsevier]

Abstract: Cuspate deltoid cobaltous oxide (CoO) crystallites with an average grain size of 3μm were obtained via developing the Co3O4 nanoplatelets under the KCl/NaCl flux atmosphere. The as-synthesized products were characterized by powder X-ray diffraction, transmission electron microscopy, field-emission scanning electron microscope and selected area electron diffraction. The electrochemical properties of the products were investigated by an Electrochemical Workstation device at room temperature. It has been found that the final prepared cubic CoO crystallites are of uniform cuspate deltoid morphology. The results of electrochemical tests indicate that the CoO shows acceptable capacitive behavior with specific capacitance about 88F/g. [Copyright &y& Elsevier]

Abstract: Chaoite-like carbon was prepared by quenching the pyrolysate of acetylene gas at 873K and ambient pressure. Its morphology is carbon macrotubes (CMTs) with 20–60μm in diameter and up to 8mm in length. Microstructure analysis revealed that sp-bonded carbon (SPBC) chains in CMTs are kinked and the crystal orientation is anisotropic along the length and circumference directions of CMTs. A SPBC belt scrolling model was proposed for explaining the formation process of CMTs. [Copyright &y& Elsevier]

Abstract: Ni–Pb/Al2O3 nanostructures having composition of Ni 84at.%, Pb 16at.% were successfully fabricated by AC electrochemically assembled within the nanopores of ordered porous alumina films prepared by a two-step anodization. SEM images revealed that the pore arrays are regularly arranged throughout the alumina film and parallel each other. TEM analyses showed that the Ni–Pb nanoarrays are polycrystalline with dimension uniformity around 20nm in diameter and lengths up to several μm. X-Ray diffraction results revealed that the Ni–Pb nanoarrays do not form metastable alloy phase. Hysteresis loops determined by VSM indicated that the Ni–Pb/Al2O3 nanostructures obtained possess obvious magnetic anisotropy, and the perpendicular coercivity is lower than that of Ni nanowires before and after annealing. [Copyright &y& Elsevier]

Ordered CoxPb1-x nanowire arrays embedded in the porous anodic aluminum oxide (AAO) template have been fabricated by electrodeposition. XRD experiments prove that neither hexagonal-close-packed (hcp) nor face-centered-cubic (fcc) Co peaks are detected when the Co component (x) is below 0.91. The coercivity (Hc) and squareness (Mr/Ms) are found to increase with ferromagnetic Co component and the maximum value is at the position x=1 (pure Co nanowires). Annealing effects cause Hc and Mr/Ms increase, which surpasses the pure Co nanowires in the 0.2

CoFe2O4 nanowire arrays with an average diameter of about 40 nm were prepared in porous anodic aluminum oxide (AAO) template using sol–gel process. Transmission electron microscopy (TEM) diffraction pattern and X-ray diffraction (XRD) showed that the nanowires were polycrystalline phase. Magnetic measurements showed the arrays of nanowires did not show a preferential magnetic orientation, the reason was briefly discussed. The effect of heating rate on the structure and magnetic properties of CoFe2O4 nanowire arrays was investigated. The result showed that the coercivity decreased with the increase of the heating rate. [Copyright &y& Elsevier]

Anion defect engineering is proven to be an efficient approach to reconstruct the electronic configuration of carbon‐based magnetoelectric materials for targeted modulation of electromagnetic (EM) performance. However, traditional mono‐anionic doping suffers from low defect concentration and lacks diverse polarization mechanisms. In this work, multi‐anions (N/S/F) stepwise‐doped carbon/Fe3C magnetoelectric composites are elaborately constructed, wherein the predesigned N defects serve as activated sites for anomalously adopting S anions (Step I) and subsequent F anions (Step II) in non‐marginal areas of the carbon layer. It is found that S prefers to replace pyrrolic N defects while F tends to form dangling bonds with the C site adjacent to the pyridinic N. Intriguingly, besides the inherent polarized resonance of N defect at ≈15 GHz, customized S and F defects induce new polarization resonances at ≈10 GHz and ≈15+ GHz, respectively. Under a typical multi‐polarization effect with the synergetic magnetic response, the carbon/Fe3C composites with N/S/F defects harvest the broadest bandwidth of 8.28 GHz (9.72–18 GHz) at 2.55 mm, covering a wide frequency range almost from X to Ku bands. This work demonstrates the positive impact of localized multi‐defects customization and multi‐polarization effect on expanding microwave absorption bandwidth, providing valuable insights for the advanced design of ultra‐broadband absorbers. [ABSTRACT FROM AUTHOR]

Energy‐efficient building materials are eye‐catching for reducing indoor energy consumption via eliminating electromagnetic interference and pollution, controlling the thermal transfer, and promoting sunlight harvesting and providing a comfortable living environment. To realize broadband microwave shielding, the elaborate control of microstructures has showed great potential and research direction. By composition regulation and structure design with various dimension, the synergistic effects including conductive networks, interfacial polarization, magnetic coupling, dipole polarization, and dielectric‐magnetic synergy, can significantly improve electromagnetic (EM) shielding capacity. Thermal management including thermal conversion, thermal storage, thermal radiation, and thermal conduction has enormous potential in enhancing the sustainability and energy efficiency for future buildings. Smart windows are able to switch optical transmittance and colors, which is contributed to saving building energy. Herein, in this review, the recent progress of broadband shielding, thermal management, and smart window in the field of energy‐efficient buildings is summarized, from the aspects of materials, mechanisms, and scenarios. Further, the main bottlenecks and problems are discussed, and potential research opportunities are further highlighted. [ABSTRACT FROM AUTHOR]

In virtue of mutually exclusive stealth mechanisms, effectively protecting from infrared detection and attenuating microwaves through composition and structure design remains a formidable challenge. To achieve high-efficiency infrared/radar compatible stealth, in this work, 0D magnetic Co nanoparticles were successfully in situ grown onto the renewable biomass chitosan-based 3D porous carbon skeletons via facile liquid reaction, freeze-drying, and calcination method. Herein, the as-prepared Co/C hybrid aerogels exhibit dielectric and magnetic coupling network, and the relevant infrared/radar compatible stealth property can be regulated by adjusting the addition amount of Co salt. The minimum thermal conductivity value reached 0.095 W m−1 K−1 at 60 °C, and the lowest infrared emissivity of 0.717 in the 8–14 μm band was also achieved. Furthermore, the minimum reflection loss (RL min) value of −44.70 dB at a relatively thin thickness of 1.35 mm and the maximum effective absorption bandwidth (EAB) of 5.45 GHz at only 1.5 mm appeared in the optimal Co/C hybrid aerogel with the most appropriate Co content. Compared with perfect conductive layer (PEC), the simulated radar cross section (RCS) signals of Co/C composites covered PEC have been significantly reduced by 18.44 dB m2 at the scanning angle of 80°. This study inspires the exploration of the elaborate design strategy and facile construction method for environment-friendly infrared/radar compatible hybrid aerogels in the future. In this work, dielectric and magnetic coupling network design strategy was proposed to achieve cobalt salt/chitosan derived Co/C hybrid aerogels, providing inspiration and reference for the development of biomass derivatives radar-infrared compatible stealth materials. [Display omitted] [ABSTRACT FROM AUTHOR]

A new restriction effect of hard templates for the shrinkage of mesoporous polymer results in anomalous increase of the mesopore size during carbonization. [ABSTRACT FROM AUTHOR]

Optimizin the efficient light‐trapping in the photothermal conversion by enhancing localized surface plasmon resonance (LSPR) is crucial in improving light‐heat‐conversion efficiency of Ti3C2Tx MXene. However, its susceptibility to oxidation makes it prone to oxides formation, diminishing its metallic properties and significantly reducing the LSPR effect. This work synthesizes a kind of air‐stable hybrid Ti3C2Tx MXenes by a synergistic densification strategy that incorporates sulfhydryl‐bonding between organic and inorganic parts by reacting Ti3C2Tx MXene with thiocarboxylic acids. The resultant shortening of electron transport pathways, enhanced charge density, and the generation of additional electronic states around the Fermi level collectively contribute to an augmented LSPR effect. Additionally, the hybrid Ti3C2Tx MXenes also demonstrate high‐temperature resistance and reduced water interactions. These combined effects substantially elevate photothermal conversion efficiency through thiocarboxylic acids modification, reaching a photothermal evaporation rate of 1.77 kg m−2 h−1 with 94.56% efficiency in hybrid Ti3C2Tx MXenes. The approach paves the way for the design and development of a three‐in‐one strategy for photothermal conversion. [ABSTRACT FROM AUTHOR]

[Display omitted] • Multi-interfacial bridging engineering was used to prepare the flexible MXene film. • Highly efficient electromagnetic shielding capability is achieved through a dense multiple conductive network. • The total EMI shielding effectiveness can be increased by 27 % with the highest value of 67.9 dB. • The infrared emissivity is as low as 0.173 within the 8–14 μm. • The mechanism of the shielding and photothermal compatibility along with the durability are proposed. Accompanied by the progressive development of electronic equipment, excellent electromagnetic interference (EMI) shielding materials display a satisfying prospect in protecting electronic devices against electromagnetic pollution/radiation, while integrating energy conversion. Heretofore, it remains a conundrum to availably construct thin films with multi-interfacial bridging engineering as multifunctional shielding devices. To effectively achieve electromagnetic wave attenuation and integrate energy conversion, a co-mixed vacuum-assisted filtration strategy is designed to synthesize Au@MXene/cellulose nanocrystal/dodecylbenzenesulfonic acid-doped polyaniline (AMCP) films. Profited from the interfacial engineering, the total EMI shielding effectiveness (SE) can be increased by 27 % with the highest value of 67.9 dB. MXene with localized surface plasmon resonance characteristics gives the composite films good energy conversion performance, that is, the composite film can be rapidly heated up to 100 °C under the irradiation of an infrared lamp, and its surface temperature remains stable after continuous irradiation. Additionally, the infrared emissivity is as low as 0.173 within the 8–14 μm, which is necessary to adapt various application scenarios. Therefore, it is reliable that the AMCP films constructed by multicomponent offer a facile strategy for MXene-based EMI shielding devices with integration characteristics. [ABSTRACT FROM AUTHOR]

Rechargeable Li–S batteries are regarded as one of the most promising next‐generation energy‐storage systems. However, the inevitable formation of Li dendrites and the shuttle effect of lithium polysulfides significantly weakens electrochemical performance, preventing its practical application. Herein, a new class of localized high‐concentration electrolyte (LHCE) enabled by adding inert fluoroalkyl ether of 1H,1H,5H‐octafluoropentyl‐1,1,2,2‐tetrafluoroethyl ether into highly‐concentrated electrolytes (HCE) lithium bis(fluorosulfonyl) imide/dimethoxyether (DME) system is reported to suppress Li dendrite formation and minimize the solubility of the high‐order polysulfides in electrolytes, thus reducing the amount of electrolyte in cells. Such a unique LHCE can achieve a high coulombic efficiency of Li plating/stripping up to 99.3% and completely suppressing the shuttling effect, thus maintaining a S cathode capacity of 775 mAh g−1 for 150 cycles with a lean electrolyte of 4.56 g A−1 h−1. The LHCE reduces the solubility of lithium polysulfides, allowing the Li/S cell to achieve super performance in a lean electrolyte. This conception of using inert diluents in a highly concentrated electrolyte can accelerate commercialization of Li–S battery technology. [ABSTRACT FROM AUTHOR]

Highlights: The frequency and intensity of multi-magnetic resonance are freely regulated by co-doping La3+ and Zr4+ ions. Zr4+ occupation is elaborately modified for promoting the portion of polarization/conduction loss to increase profoundly. The optimized electromagnetic characteristics lead to an ultra-wide bandwidth of 12.5+ GHz around millimeter-wave atmospheric window. The utilization of electromagnetic waves is rapidly advancing into the millimeter-wave frequency range, posing increasingly severe challenges in terms of electromagnetic pollution prevention and radar stealth. However, existing millimeter-wave absorbers are still inadequate in addressing these issues due to their monotonous magnetic resonance pattern. In this work, rare-earth La3+ and non-magnetic Zr4+ ions are simultaneously incorporated into M-type barium ferrite (BaM) to intentionally manipulate the multi-magnetic resonance behavior. By leveraging the contrary impact of La3+ and Zr4+ ions on magnetocrystalline anisotropy field, the restrictive relationship between intensity and frequency of the multi-magnetic resonance is successfully eliminated. The magnetic resonance peak-differentiating and imitating results confirm that significant multi-magnetic resonance phenomenon emerges around 35 GHz due to the reinforced exchange coupling effect between Fe3+ and Fe2+ ions. Additionally, Mössbauer spectra analysis, first-principle calculations, and least square fitting collectively identify that additional La3+ doping leads to a profound rearrangement of Zr4+ occupation and thus makes the portion of polarization/conduction loss increase gradually. As a consequence, the La3+–Zr4+ co-doped BaM achieves an ultra-broad bandwidth of 12.5 + GHz covering from 27.5 to 40 + GHz, which holds remarkable potential for millimeter-wave absorbers around the atmospheric window of 35 GHz. [ABSTRACT FROM AUTHOR]

Morphology and phase regulation shed light on the tuning of microwave absorbing characteristics, as well as magnetic and optical features. Not only is the development of electromagnetic wave absorbing materials the best way to equip us against harmful electromagnetic waves in the technology era, but the widespread applications of microwave absorbers in military and civilian fields have also enhanced their importance. Hence, MgFe 2 O 4 nanoparticles were synthesized, and then (1) its main crystalline phase was divided into Mg, Fe 2 O 3 , and Fe 3 O 4 , and (2) its morphology was manipulated to evaluate the influence of morphology and phase on the microwave absorbing performance, optical characteristics, and magnetic capability. The novel precursors, along with modified sol-gel and solvothermal scenarios, were applied to regulate the structures toward strengthening the features. Interestingly, polyethylene terephthalate (PET) was chosen as the recyclable plastic to fabricate the final composites to evaluate the microwave absorbing/shielding characteristics due to its fascinating susceptibilities as building materials, minimizing environmental hazards and implementing green and sustainable manufacturing. Noticeably, Mg/Fe 3 O 4 /PET nanocomposite gained a brilliant RL of −95.50 dB at 21.80 GHz meanwhile the one-pot-synthesized Fe 2 O 3 /MgFe 2 O 4 composited by PET attained a maximum RL of −71.32 dB at 23.06 GHz and an ultra-high efficient bandwidth (RL ≤ −20 dB) of 8.50 GHz with only thickness of 0.50 mm. Interestingly, the PET-based microwave absorbers were fabricated with a low filling ratio of 10 wt%. More significantly, the samples illustrated proper shielding efficiency, desirable for practical applications in the modern era. [Display omitted] [ABSTRACT FROM AUTHOR]

Electromagnetic pollution and cancer are phenomena that essentially endanger the future of humanity. Herein, multiple approaches are being proposed to solve the aforementioned issues. Recent studies have demonstrated that by regulating the morphology, defect, and phase of materials, their microwave absorbing, optical, and hyperthermia properties are tunable. Calcium ferrite with proper dielectric, magnetic, and biocompatible characteristics was chosen as a substantial candidate to promote its microwave-absorbing properties by regulating its structure. Spinel CaFe2O4 was synthesized through sol–gel and solvothermal routes and its phase, defect, and morphology were manipulated using innovative procedures. Glucose was applied as conventional defecting and templating agent; interestingly, a dendrimer was designed to bear and form nanoparticles. More importantly, a novel reductive process was designed to fabricate one-put Ca/Fe3O4 using a solvothermal method. Particularly, polypropylene (PP) was employed as a practical polymeric matrix to fabricate the eventual product. Structures were molded at a low filling ratio to evaluate their optical and microwave-absorbing performance. As expected, defects, morphology, and phase play a pivotal role in tuning the optical and microwave-absorbing properties of calcium ferrite derivates. Interestingly, the dendrimer-assisted (D-A) formation of CaFe2O4 demonstrated a fascinating reflection loss (RL) of 70.11 dB and an efficient bandwidth (RL ≤ −20 dB) of 7.03 GHz with ultralow thickness (0.65 mm) and filling ratio (10 wt%), attaining proper shielding efficiency (SE) and hyperthermia desirable for its practical application as a material for shielding buildings and cancer therapy. The presented perspective develops new inspirations for architecting microwave absorbing/shielding materials with advanced applications in therapeutic issues. [ABSTRACT FROM AUTHOR]

Promoting advanced functional films that integrate protective behaviors for synergetic radar, infrared (IR), and visible light is confronted with extreme challenges. The effective integration of shielding capacity and IR camouflage into single‐component carbon films remains an enormous challenge because of limited conductivity and high IR absorption. In this work, carbon nanotube (CNT) films with excellent electromagnetic interference (EMI) shielding, switchable IR camouflage, and energy conversion are obtained via a (FCCVD) method and subsequent defect engineering strategies induced by temperature (Strategy I) and N/S co‐doping (Strategy II). Wherein the effect on the electronic configuration as well as multi‐spectra performance is deeply explored. Ascribing to the synergistic effects of strategies, defective CNT films present superior EMI shielding effectiveness (SE) with a high absorption effectiveness ratio of 86.9%, and a large span of emissivity (0.479), which provides the necessary condition for various application scenarios. Under the applied electric field excitation, the IR radiation of CNT films can adapt to rapidly changing surroundings, such as low‐high/high‐low temperatures. Besides, the desirable energy conversion performance and de‐icing can be achieved. This work supplies a feasible strategy for designing EM absorption, adaptive IR camouflage, and energy conversion to confront multiband surveillance. [ABSTRACT FROM AUTHOR]

To design and develop efficient microwave absorbents via phase engineering is still less studied. The unique properties caused by constructing heterophase structure hold the potential to strengthen absorbing capability toward microwave radiation. Herein, amorphous/crystalline γ‐Fe2O3 nanosheets (Fe‐H) are carefully fabricated through a controlled annealing process. The matched Fermi levels formed on both sides of the heterophase interface not only provides efficient interfacial polarizations but also facilitates the transport of electrons with less scattering over the whole Fe‐H nanosheets. Thereby, both of the conduction loss and dielectric polarization relaxation are promoted, leading to a strengthened attenuation toward electromagnetic wave radiation. The as‐synthesized Fe‐H sample exhibited a minimum reflection loss of ‐89.5 dB centered at a thickness of 2.00 mm, associated with an effective absorption bandwidth (reflection loss ≤ ‐10 dB) reaching 6.45 GHz. All of these behaviors are superior to its pure amorphous absorbent and bare crystalline counterpart. Furthermore, this heterophase engineering strategy is valid when extended to Co and Ni based oxides, suggesting its universality and generality for promoting microwave absorption. Henceforth, this study indicates a favorable potential of the synthesis and application of amorphous/crystalline materials as heterophase microwave absorbents. [ABSTRACT FROM AUTHOR]

In this work, multiple interface design strategies were proposed to achieve excellent electromagnetic wave absorption and low Infrared emissivity. In addition, the obtained composite aerogel maintains great thermal stealth capability. Hence, this work provides directions for the design of carbon-based radar-infrared compatible stealth materials. [Display omitted] • Multiple interface design strategies are proposed for the preparation of radar-infrared compatible stealth materials. • The prepared aerogel obtains an effective absorption bandwidth of 6.62 GHz with a filling ratio of 20 wt%. • The as-prepared aerogel achieves 41 % reduction of IR emissivity in the 8–14 μm band compared to the carbon materials. • The composite aerogel maintains excellent thermal stealth capability. Radar-infrared (IR) compatible stealth can satisfy the characteristics of excellent electromagnetic wave attenuation property and low infrared emissivity. However, concurrently satisfying these demands is still a great challenge at present. Herein, multi-interfacial engineering strategy was proposed for the preparation of radar-IR compatible stealth materials. ZnO has a high electron binding energy and a large band gap at room temperature, and doping with sulphide can increase the concentration of unconstrained carriers. Therefore, bimetallic sulphide aerogels loaded with ZnO were prepared by means of carbonization and vulcanization, combined with freeze-drying method. When the filling ratio is 20 %, an absorption bandwidth (f e) of 6.62 GHz at a matching thickness of 2.0 mm and a reduction in IR emissivity from 0.920 to 0.539 in the 8–14 μm band are achieved. This work provides a guidance to design and synthesize high-performance absorbers by multi-interfacial engineering for IR-radar compatible stealth application. [ABSTRACT FROM AUTHOR]

A correction to the article "Facile Aluminum Reduction Synthesis of Blue TiO2 with Oxygen Deficiency for Lithium-Ion Batteries" is presented.

Hydrotalcite-like CoFeAl-layered double hydroxide sheets (CoFeAl-LDH) are employed to construct the CoFeAl-LDH/G hybrids via the sufficient metal ions absorption and subsequent in-situ growth on graphene oxide (GO) surfaces. The uniform integration not only retains the inherent excellent properties of GO, but also overcomes some weakness like shallow skin depth and severe layers restack. In addition, extra dipolar polarization (induced by donated electron from GO) and Maxwell-Wagner-Sillars (MWS) effect (caused by abundant charges accumulation at the interfaces) also contribute to the remarkable microwave absorption performance. The maximum RL value and the effective bandwidth reach −23.8267 dB and 7.36 GHz, respectively at 2.5 mm. Consequently, study of structure-performance relationship is meaningful for the design and fabrication of binary absorbers with effective microwave absorption. [ABSTRACT FROM AUTHOR]

Dielectric materials are eternal jewels in the view of research due to their strong dissipation ability, low density and higher stability compared to those of magnetic materials. Regarding the significance of permittivity to characterize the dielectric properties of dielectrics, an in-depth and systematical investigation of dielectric polarization process has become quite necessary. Updated and critical surveys of the key factors determining permittivity, dielectric polarization in single-component system, dielectric polarization in multi-component system and related polarization relaxation are all highlighted. In addition, the challenges for dielectric polarization and polarization relaxation, the prospects for further exploration in electromagnetic wave absorption are also discussed. In short, this review provides a brief but systematic introduction to dielectric polarization and related polarization relaxation in electromagnetic wave absorption, which motivates further study of dielectric absorbers in microwave absorption field. [ABSTRACT FROM AUTHOR]

Highlights: A multi-scale structural carbon fiber-based composite was synthesized through the assembly of one-dimensional materials. The construction of multiple conductive networks makes the composite have a strong EMI shielding performance of 73.9 dB. The reasonable design endows the composite with excellent positive and passive thermal management properties. Wearable devices with efficient thermal management and electromagnetic interference (EMI) shielding are highly desirable for improving human comfort and safety. Herein, a multifunctional wearable carbon fibers (CF) @ polyaniline (PANI) / silver nanowires (Ag NWs) composites with a "branch-trunk" interlocked micro/nanostructure were achieved through "three-in-one" multi-scale design. The reasonable assembly of the three kinds of one-dimensional (1D) materials can fully exert their excellent properties i.e., the superior flexibility of CF, the robustness of PANI, and the splendid conductivity of AgNWs. Consequently, the constructed flexible composite demonstrates enhanced mechanical properties with a tensile stress of 1.2 MPa, which was almost 6 times that of the original material. This is mainly attributed to the fact that the PNAI (branch) was firmly attached to the CF (trunk) through polydopamine (PDA), forming a robust interlocked structure. Meanwhile, the composite possesses excellent thermal insulation and heat preservation capacity owing to the synergistically low thermal conductivity and emissivity. More importantly, the conductive path of the composite established by the three 1D materials greatly improved its EMI shielding property and Joule heating performance at low applied voltage. This work paves the way for rational utilization of the intrinsic properties of 1D materials, as well as provides a promising strategy for designing wearable electromagnetic protection and thermal energy management devices. [ABSTRACT FROM AUTHOR]

In this study, an extremely simple one-step ball milling has been applied to fabricate the flaky Fe 3 O 4 /Fe composites. The obtained samples were characterized by X-ray diffraction (XRD), scanning electron microscopy (SEM), vibrating sample magnetometer (VSM), and vector network analysis (VNA). It is acknowledged that the ball-milling process has huge influence on the morphology and electromagnetic absorption capability. Compared with the raw Fe 3 O 4 , the saturation magnetization of Fe 3 O 4 /Fe composites improved greatly. When the thickness is just 1.25 mm, the reflection loss values below −10 dB can be achieved from 13.8 to 18 GHz, with a maximum reflection loss of −25.9 at 16.1 GHz. Obviously, the Fe 3 O 4 /Fe composites can be used as magnetic microwave absorbers due to its simple synthesis for the mass production standards. Moreover, this study also gives new enlightenment to design other magnetism/magnetism composites that can be applied to Ku-band such as satellite communications. [ABSTRACT FROM AUTHOR]

In recent years, metal–organic-frameworks derived composites, especially magnetic nanoparticles embedded in porous carbon matrix have emerged as promising candidate for lightweight electromagnetic wave absorber. Nevertheless, investigation on the optimization of impedance matching in the microwave absorption properties is insufficient. In this work, impedance matching is optimized to achieve strongest absorption intensity and broaden the effective frequency bandwidth. In detail, electromagnetic parameters have been controlled through changing the carbonization temperature to fulfill optimized impedance matching. RL value of −51.8 dB and an effective frequency bandwidth ( f e ) of 3.48 GHz with a thickness of 2.6 mm can be achieved by sample prepared at 500 °C and RL value of −15.0 dB and a f e of 4.72 GHz with a thin thickness of 1.8 mm can be reached by sample synthesized at 600 °C. Comparative studies of each sample directly display the effect of impedance matching on the RL performance and possible attenuation mechanisms are also discussed. This work may deepen the understanding of the impedance matching and pave the way for the synthesis of high performance lightweight microwave absorber. [ABSTRACT FROM AUTHOR]

Porous carbon materials have long been regarded as promising candidate for high-performance lightweight microwave absorption materials owing to their strong attenuation abilities, tunable dielectric properties and low density. Nevertheless, previous work mainly focused on binary composites (usually carbon and magnetic fillers), which show limited loss mechanisms. The effect (except temperature) on the interfacial polarization and electromagnetic properties has rarely been investigated. Thus, a series of bimetallic zeolitic imidazolate frameworks (BMZIFs) with designed compositions and highly porous structures were selected to be converted to porous carbon-wrapped semiconductors (ZnO, Co3ZnC) and magnetic metal (Co) composites. Strong dielectric loss capabilities could be provided by graphitic carbon and enhanced interfacial polarization induced by multiple components and unique microstructures. By changing the molar ratio of Zn/Co under a fixed carbonization temperature, the interface of this multicomponent system could be adjusted, which influenced the electromagnetic properties. When evaluated as microwave absorption material, a reflection loss of −32.4 dB could be achieved with a broad effective frequency bandwidth of 5.24 GHz at only 1.9 mm. This work may provide an effective method to modify the physical and chemical properties of porous carbon materials with a desired complex structure and excellent microwave absorption performance. [ABSTRACT FROM AUTHOR]

Broadband electromagnetic wave absorbers are of great significance in military and civil fields. Absorbent coatings, although highly conformal, suffer from a narrow absorption band and a single absorption mechanism. In this work, inspired by the idea of bionics, we extracted the structural model of the moth-eye and designed the structure size by using electromagnetic simulation. Conductive graphite powder was selected as the wave absorbing agent due to its good dielectric and conductivity losses, and the final products were prepared according to the structural parameters obtained from the simulation. The result shows that the frequency bandwidth with absorption rate above 90% (reflection loss < −10 dB) of the products could reach 13 GHz, including C, X and Ku bands. The equivalent electromagnetic parameters of the bionic structure absorber were extracted by the inversion method, and its impedance gradient absorption mechanism was revealed by combining with the transmission line theory. In order to optimize low frequency (S-band) absorption, the introduction of Salisbury screen and bionic structure absorber combinations to form a composite absorber, the low-frequency absorption performance is effectively improved. The work shows that the combination of two absorption mechanisms, impedance gradient and interference, could effectively improve the absorption bandwidth of electromagnetic waves, providing a good idea for the design of the carbon-based broadband absorber. [Display omitted] • Broadband microwave absorber was prepared by bionic anti-reflective model and conductive graphite absorbent. • Equivalent electromagnetic parameters of structural absorbers was extracted by inversion method. • The absorption mechanism of the impedance gradient was obtained by transmission line theory. • Full band absorption from 2 GHz to 18 GHz by combining Salisbury screen and bionic structure absorber was obtained. [ABSTRACT FROM AUTHOR]

The development of infrared‐radar compatible materials/devices is challenging because the requirements of material properties between infrared and radar stealth are contradictory. Herein, a composite of poly(3, 4‐ethylenedioxythiophene):polystyrene sulfonate (PEDOT:PSS) coated melamine foam is designed to integrate the advantages of the dual materials and the created heterogeneous interface between them. The as‐designed PEDOT:PSS@melamine composite shows excellent mechanical properties, outstanding thermal insulation, and improved thermal infrared stealth performance. The relevant superb radar stealth performance including the minimum reflection loss value of −57.57 dB, the optimum ultra‐wide bandwidth of 10.52 GHz, and the simulation of radar cross section reduction value of 17.68 dB m2, can be achieved. The optimal specific electromagnetic wave absorption performance can reach up as high as 3263.02 dB·cm3 g−1. The average electromagnetic interference shielding effectiveness value can be 30.80 dB. This study provides an approach for the design of high‐performance stealth materials with infrared‐radar compatibility. [ABSTRACT FROM AUTHOR]

Highlights: The whole bamboo mere made directly into cellulose composites, which greatly reduced massive energy consumption from the mechanical pre-processing process. The wall thickness of transparent whole bamboo can reach 6.23 mm. The modified whole bamboo possesses excellent optical transmittance of about 60% at 6.23 mm, the illuminance of 1000 luminance (lux), water absorption stability (the mass change rate less than 4%), longitudinal tensile strength (46.40 MPa), and surface properties (80.2 HD). The combination of excellent transmittance, mechanical properties, surface properties, thermal performance, and electromagnetic shielding properties makes this composite attractive in areas such as transparent, energy-saving, and electromagnetic shielding buildings. Currently, light-transmitting, energy-saving, and electromagnetic shielding materials are essential for reducing indoor energy consumption and improving the electromagnetic environment. Here, we developed a cellulose composite with excellent optical transmittance that retained the natural shape and fiber structure of bamboo. The modified whole bamboo possessed an impressive optical transmittance of approximately 60% at 6.23 mm, illuminance of 1000 luminance (lux), water absorption stability (mass change rate less than 4%), longitudinal tensile strength (46.40 MPa), and surface properties (80.2 HD). These were attributed to not only the retention of the natural circular hollow structure of the bamboo rod on the macro, but also the complete bamboo fiber skeleton template impregnated with UV resin on the micro. Moreover, a multilayered device consisting of translucent whole bamboo, transparent bamboo sheets, and electromagnetic shielding film exhibited remarkable heat insulation and heat preservation performance as well as an electromagnetic shielding performance of 46.3 dB. The impressive optical transmittance, mechanical properties, thermal performance, and electromagnetic shielding abilities combined with the renewable and sustainable nature, as well as the fast and efficient manufacturing process, make this bamboo composite material suitable for effective application in transparent, energy-saving, and electromagnetic shielding buildings. [ABSTRACT FROM AUTHOR]

Highlights: The CuS@rGO composite aerogel can achieve the broad effective absorption bandwidth (EAB) of 8.44 GHz with the filler content of 6 wt%. The RLmin of CuS@rGO composite aerogel is -55.1 dB and EAB is 7.2 GHz with the filler content of 2 wt% by ascorbic acid thermal reduction. The radar cross-section reduction value of CuS@rGO composite aerogel can reach 53.3 dB m2. The CuS@rGO composite aerogels possess lightweight, compression and recovery, radar-infrared compatible stealth properties. Developing ultrabroad radar-infrared compatible stealth materials has turned into a research hotspot, which is still a problem to be solved. Herein, the copper sulfide wrapped by reduced graphene oxide to obtain three-dimensional (3D) porous network composite aerogels (CuS@rGO) were synthesized via thermal reduction ways (hydrothermal, ascorbic acid reduction) and freeze-drying strategy. It was discovered that the phase components (rGO and CuS phases) and micro/nano structure (microporous and nanosheet) were well-modified by modulating the additive amounts of CuS and changing the reduction ways, which resulted in the variation of the pore structure, defects, complex permittivity, microwave absorption, radar cross section (RCS) reduction value and infrared (IR) emissivity. Notably, the obtained CuS@rGO aerogels with a single dielectric loss type can achieve an ultrabroad bandwidth of 8.44 GHz at 2.8 mm with the low filler content of 6 wt% by a hydrothermal method. Besides, the composite aerogel via the ascorbic acid reduction realizes the minimum reflection loss (RLmin) of − 60.3 dB with the lower filler content of 2 wt%. The RCS reduction value can reach 53.3 dB m2, which effectively reduces the probability of the target being detected by the radar detector. Furthermore, the laminated porous architecture and multicomponent endowed composite aerogels with thermal insulation and IR stealth versatility. Thus, this work offers a facile method to design and develop porous rGO-based composite aerogel absorbers with radar-IR compatible stealth. [ABSTRACT FROM AUTHOR]

In this study, a novel graphene/g-C3N4 microwave absorber is developed to solve the electromagnetic wave interference problem. Graphene/g-C3N4 composite is synthesized by loading g-C3N4 nanosheets on graphene through a simple liquid-phase approach. High-performance electromagnetic absorption performance can be achieved. The optimal reflection loss value is up to −29.6 dB under a thin coating layer of 1.5 mm. At the same time, the corresponding absorption bandwidth of this composite can reach 5.2 GHz (12.8-18 GHz). Excellent electromagnetic absorption property may be attributed to the current attenuation theory which has been proven by replacing graphene with porous graphene or graphene oxide. The results reveal that free electron numbers and loading mass of g-C3N4 on graphene play the key roles in the intensity of current attenuation and resistance value. [ABSTRACT FROM AUTHOR]