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Due to high theoretical specific capacity, energy density, and low-cost lithium-sulfur (Li-S) batteries became the most potential energy storage devices for the next generation. The harsh shuttling effect, poor electroconductibility of sulfur, and volume change affect the Li-S battery's practical application. Herein, the rational design of porous hollow carbon aerogel (PHCA) with an ultra-high specific surface area of 2054.5 m2 g−1 and outstanding adsorption ability is firstly fabricated to restrict the shuttling effect of lithium polysulfides (LiPSs) by using commercialized nano-CaCO 3 as a template. As a sulfur host, the S/PHCA cathode delivers initially discharge specific capacity of 992.7 mAh g−1 with an average Coulombic efficiency of 97.6%. After 200 cycles, it obtains the reversible specific capacities of 600.1 mAh g−1 for S/PHCA cathode at 0.1C (2.2 mg cm−2) corresponding to 60.45% of their initial discharge specific capacity. As a PHCA interlayer, the Li-S battery with the PHCA interlayer exhibits initially discharge specific capacity of 1267.7 mAh g−1 with an average Coulombic efficiency of 99.36% at 0.1C (3.2 mg cm−2) and maintains at 863.3 mAh g−1 with the discharge specific capacity retention rate of 69.2%. This is an effective strategy to improve the outstanding electrochemical performance which is beyond reported carbon materials, which is attributed to stronger adsorption of LiPSs by the micropore. This work provides a new direction for the modification of a sulfur host and interlayer and simultaneously reveals the relationship between the heteroatom distribution and LiPSs. • The porous hollow carbon aerogel with an ultra-high specific surface area as a sulfur host and interlayer to absorb LiPSs. • The abundant porous structure acts as a lubricant role between LiPSs and the heteroatom of the PHCA. • Li-S batteries with a lightweight PHCA interlayer exhibit the outstanding electrochemical performance. • The areal density of the PHCA interlayer is only 0.008 mg cm−2. [ABSTRACT FROM AUTHOR]

Superior electromagnetic (EM) wave absorption properties in 8.2–12.4 GHz (X-band) can be obtained via the effective combination of polyaniline (PANI) and SnO 2 nanoparticle cluster. In this work, SnO 2 nanoparticle cluster@PANI (SnO 2 @PANI) core-shell microspheres were firstly fabricated via a hydrothermal process followed by in-situ polymerization, and the EM wave absorption properties of SnO 2 @PANI core-shell microspheres in X band were studied. The related structure and morphology analyses indicated SnO 2 @PANI core-shell microspheres were successfully synthesized with PANI coated on the surface of SnO 2 nanoparticle cluster. The minimum reflection loss (RL min) of − 69.1 dB (thickness of 2.78 mm) and effective absorption bandwidth (EAB) covering the whole X-band (when the thickness was from 2.5 to 3.1 mm) was achieved. Remarkable EM wave absorption properties of SnO 2 @PANI core-shell microspheres were mainly attributed to the outstanding impedance matching characteristic and dielectric loss capability (conduction loss, interfacial polarization loss and dipole polarization loss). • SnO 2 @PANI core-shell micropheres have been synthesized via a hydrothermal process followed by in-situ polymerization. • The excellent reflection loss of SnO 2 @PANI core-shell micropheres is − 69.1 dB with a matching thickness of 2.78 mm. • The effective absorption bandwidth of SnO 2 @PANI core-shell micropheres could cover the whole X-band. [ABSTRACT FROM AUTHOR]

A simple synthesize method of hybrid transition metal oxides is important for the application of electrodes materials. In this work, we report one-pot hydrothermal method to synthesize 3D hierarchical MnMoO 4 /NiWO 4 microspheres. Notably, the 3D hierarchical MnMoO 4 /NiWO 4 microspheres electrodes with a MnMoO 4 /NiWO 4 molar ratio of 4:3 present outstanding electrochemical performance. The excellent specific capacitance of the hybrid materials is 598 F g -1  at a discharge current density of 1 A g −1 and the capacitance retains 82% of its initial capacitance even after 5000 cycles, which are attributed to the obtained 3D hierarchical MnMoO 4 /NiWO 4 microspheres are constituted by self-assembly MnMoO 4 nanoflakes and NiWO 4 nanoparticals and feature with abundant transportation shortcuts for electrolyte ions and excellent electrochemical performance. The results reveal that the 3D hierarchical MnMoO 4 /NiWO 4 microspheres have great application prospect for electrochemical energy storage and the quick and facile method provides a new avenue for the preparation of hybrid materials. [ABSTRACT FROM AUTHOR]

Uniform Ag and Si layers were successfully prepared on the surface of graphite films (GF) to improve thermal conductivity (TC) by physical vapor deposition method (PVD). The results demonstrate that the unique cubic crystal structure of Ag layer with different deposition time show good interface bonding and no carbide product of Ag/GF composites. Meanwhile, the dense Si coating contribute to the enhancement of the thermal diffusion ability. The Ag/GF composites with the deposition time of 2 h possess the best comprehensive property with the TC of 9.93 (W/m·K), which is approximately 73.30% higher than untreated GF. The TC of Si/GF composites reach the maximum TC of 11.12 W/(m·K) and increase about 101.81% due to the nano-Si layer comparing with untreated GF. Those composites with high performance make them promising thermal management laminated materials. • Designing of three-dimensional structure of nano-plating benefits the surface property of heat export and displays strong bonding force with matrix (graphite film). • The TC of Si/GF composite increase about 101.81% due to the nano-Si layer. The performance of Ag/GF composites show an increase of 73.30% in TC. • Application of the Ag/GF and Si/GF composites make it potentially as one of the most promising thermal management materials for the stability of equipment. [ABSTRACT FROM AUTHOR]