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The core–shell Ni@C submicrospheres were fabricated by sintering method and combined with PVDF to prepare Ni@C/PVDF composite, which possessed optimal wave absorption property with RL min of −71.32 dB and EAB of 5.62 GHz at 1.95 mm.

Herein, from the perspective of gaining the excellent microwave absorption performances, we decorated flower like MoS2 nanoflates on the cubic phase NiS2 and adjusted the adherent MoS2 content to construct different NiS2@MoS2 core-shell structures via a facile hydrothermal process. Besides, we also properly regulated the complex relative permittivity originated from NiS2@MoS2 content in the PVDF to optimize impedance matching behaviors. And the real and imaginary parts of permittivity gradually increase with the increase content of NiS2@MoS2 composite in PVDF and decrease of MoS2 supported on the surface of NiS2 For the filler content of 20 wt%, the NiS2@MoS2-0.065 composites covered with moderate MoS2 nanosheets exhibit an optimal reflection loss of −57.35 dB at 8.16 GHz and effective absorption bandwidths of 4.0 GHz. Moreover, we believe that as-synthesized NiS2@MoS2 core-shell structure is a reliable strategy to facilitate advancements of microwave absorbers.

One-dimensional MoO3 /MoS2 hybrid composites were synthesized by hydrothermal synthesis, and flexible MoO3 /MoS2 /PVDF nanocomposites could be prepared in a controlled fashion by combining the MoO3 /MoS2 composites with polyvinylidene fluoride (PVDF) matrix. The MoO3 /MoS2 /PVDF hybrids with a low filler content (20 wt %) exhibited distinct microwave absorption properties in the range of 2-18 GHz. The minimum reflection loss can reach -38.5 dB at 8.7 GHz, and the reflection loss was less than -10 dB in the frequency range from 3.03-11.02 GHz with an absorber thickness of 2.0-5.0 mm. The MoO3 /MoS2 /PVDF nanocomposites exhibited better absorption properties than pure MoO3 and MoS2 . The possible microwave absorption mechanism was also discussed in detail.

MoO3 nanowires were synthesized by a wet chemical process and then coated by glucose, and finally successfully turned into Mo2C@C nanorods by carbonation reaction. An excellent absorption strength of −39.0 dB and absorption bandwidth of 12.2 GHz in the thickness range of 2.0–5.0 mm were achieved by the Mo2C@C/PVDF with 10% filler content, derived from effective Debye dipolar relaxation processes. It is expected that the composite can be applied as a novel and desirable microwave absorber.

Hierarchically porous materials containing interconnected macro-/meso-/micropores are promising candidates for energy storage, catalysis, and gas separation. Here, we present an effective approach for synthesizing three-dimensional (3D) sulfonated graphene coupled microporous organic polymers (SG–MOPs). The resulting SG–MOPs possess uniform macropores with an average size of ca. 350 nm, abundant mesopores, and micropores with an average size of ca. 0.6 nm. The SG-supported adsorbents exhibit a high nitrogen content (more than 38.1 wt %), high adsorption capacity (up to 3.37 mmol CO2 g–1), high CO2/N2 selectivity from 42 to 51, moderate heat of adsorption, as well as good stability because of the hierarchical porous structure and excellent thermal conductivity of the SG scaffold. Thus, these nitrogen-enriched adsorbents allow the overall CO2 capture process to be promising and sustainable.

In order to tune the microwave absorption together with the electromagnetic shielding performance, reduced graphene oxide (rGO) and Fe3O4@SiO2 nanochains are successfully combined with various mass ratio. By properly adjusting the permittivity and permeability derived from different contents of the rGO and Fe3O4@SiO2 nanochains, the rGO/Fe3O4@SiO2 composite with excellent microwave absorption properties is obtained. And due to adding the highly conductive rGO, the desired shielding effectiveness is also achieved. The reflection loss value of -48.34 dB is achieved for the composite with mass ratio of 1:1, and the bandwidth less than -10 dB can reach up to 4.88 GHz with a thickness of 2.0 mm. Moreover, the composite with mass ratio of 4:1 exhibits superior electromagnetic shielding performance as high as 37 dB, which also broaden its application fields. Considering the outstanding microwave absorption and electromagnetic shielding performance, the composite can be employed as a potential multi-functional material.

MoO

It was reported that the main obstacle of Li2ZrO3 as high-temperature CO2 absorbents is the very slow CO2 sorption kinetics, which are ascribed to the gradual formation of compact zirconia and carbonate shells along with inner unreacted lithium zirconate cores; accordingly, the “sticky” Li+ and O2– ions have to travel a long distance through the solid shells by diffusion. We report here that three-dimensional interconnected nanoporous Li2ZrO3 exhibiting ultrafast kinetics is promising for CO2 sorption. Specifically, nanoporous Li2ZrO3 (LZ-NP) exhibited a rapid sorption rate of 10.28 wt %/min with an uptake of 27 wt % of CO2. Typically, the k1 values of LZ-NP (kinetic parameters extracted from sorption kinetics) were nearly 1 order of magnitude higher than the previously reported conventional Li2ZrO3 reaction systems. Its sorption capacity of 25 wt % within ∼4 min is 2 orders of magnitude faster than those obtained using spherical Li2ZrO3 powders. Furthermore, nanoporous Li2ZrO3 exhibited good stability ov...

An effective strategy to improve the conductivity of MnO2-based electrodes is to combine them with some conductive materials, such as metal or carbon-based materials. In this work, Ag nanoparticles decorated MnO2/Sulfonated Graphene composite with 3D macroporous structure (3D Ag–MnO2/SG) was synthesized and their performance as electrode material in supercapacitors was studied. The improved conductivity and the elaborate design of 3D porous structure allowed the 3D Ag–MnO2/SG electrode to possess enhanced electrochemical performance. For example, the electrochemical testing results demonstrated that the 3D Ag–MnO2/SG presents a capacitance of 537 F g−1 at 0.5 A g−1, which is much higher than that of MnO2 (∼172 F g−1). Moreover, the 3D Ag–MnO2/SG electrode delivers a higher capacity retention rate in high current density and smaller charge transfer resistance than that of MnO2, which is contributed by the synergistic effect from the Ag nanoparticles and the 3D porous SG.

A template-assisted and morphology-controllable synthesis of 3D sulfonated graphene (SG) architectures was reported. The morphology can be controlled between a hollow nanobeads structure and macro-porous structure. The assembly mechanisms are investigated with respect to influencing factors including surface charge of the templating beads and pH value of the precursory solutions. The structures of these SG nanostructures are characterized by scanning electron microscopy (SEM) and transmission electron microscopy (TEM). In the application of the Li-ion battery, a maximum specific capacity of 865.5 mA h g−1 for the macro-porous SG electrode is achieved at a current density of 100 mA g−1. Furthermore, even after 100 cycles, more than 99.0% of the specific capacity is still maintained. In the application of supercapacitors, a maximum specific capacity of 256.25 F g−1 for the hollow nanobead SG cell is achieved at a current density of 0.5 A g−1 and a satisfactory capacity retention is also obtained even after 1000 cycles.

One-dimensional MoO

Three polymeric heterometallic clusters with 1D, 2D, and 3D frameworks, constructed from a cyclic vanadate {V4O12}(4-) building block and three geometric constraint ligands, were synthesized by a one-pot self-assembly reaction. Z-scan experiments demonstrated that all the three cluster polymers have large hyperpolarizability gamma values. TD-DFT calculations afforded insight into the electronic transitions and spectral characterization of these novel NLO molecular materials.

New covalently tethered CO2 adsorbents are synthesized through the in situ polymerization of N-carboxyanhydride (NCA) of l-alanine from amine-functionalized three-dimensional (3D) interconnected macroporous silica (MPS). The interconnected macropores provide low-resistant pathways for the diffusion of CO2 molecules, while the abundant mesopores ensure the high pore volume. The adsorbents exhibit high molecular weight (of up to 13058 Da), high amine loading (more than 10.98 mmol N g(-1)), fast CO2 capture kinetics (t1/21 min), high adsorption capacity (of up to 3.86 mmol CO2 g(-1) in simulated flue gas and 2.65 mmol CO2 g(-1) in simulated ambient air under 1 atm of dry CO2), as well as good stability over 120 adsorption-desorption cycles, which allows the overall CO2 capture process to be promising and sustainable.

In the title compound, [CuBr2(C5H6N2)4], the CuII cation is located on a crystallographic centre of symmetry and coordinated by four N atoms from four 1-vinyl­imidazole ligands and two trans coordinated Br− anions in a distorted octa­hedral geometry. In the crystal structure, intra- and inter­molecular C—H⋯Br hydrogen bonds form three-dimensional hydrogen-bond networks which stabilize the structure.