Synthesis, characterization and microwave absorption of carbon-coated Sn nanorods

Cu2ZnSnS4 nanocrystals for microwave thermal and microwave dynamic combination tumor therapy

Cu2ZnSnS4 nanocrystals (CZTS NCs) have been demonstrated to be effective in tumor therapy as a novel susceptible agent for microwave thermal and microwave dynamic therapy. CZTS NCs intensify the heating effect of microwaves with a significant temperature increase of about 15 °C compared to the control group and showed remarkable anti-tumor performance after 5 min of microwave irradiation. For the first time, we report the microwave absorption performance and singlet oxygen production of CZTS NCs used in microwave therapy, which reveals new opportunities for novel combined mechanisms of microwave thermal and microwave dynamic tumor therapies.

Tunable design of yolk–shell ZnFe2O4@RGO@TiO2 microspheres for enhanced high-frequency microwave absorption

Yolk–shell ZnFe₂O₄@RGO@TiO₂ microspheres with a tunable void size and TiO₂ shell thickness possess enhanced high-frequency microwave absorption properties.

Nanocasting synthesis of Fe3O4@HTC nanocapsules and their superior electromagnetic properties

Fe₃O₄@HTC nanocapsules synthesized using a nanocasting method exhibited enhanced electromagnetic wave attenuation properties.

A promising broadband and thin microwave absorber based on ternary FeNi@C@polyaniline nanocomposites

Ternary FeNi@C@polyaniline (PANI) nanocomposites are synthesized by combining the arc-discharge process and anin situchemical oxidative polymerization reaction, and can be seen as a good candidate for microwave absorbents with a broad bandwidth.

Polarization enhancement of microwave absorption by increasing aspect ratio of ellipsoidal nanorattles with Fe3O4 cores and hierarchical CuSiO3 shells

The shape anisotropy of the nanostructured nanorattles is one of the key factors that affect their microwave absorption performance. In the present study, the microwave absorption performance of ellipsoidal Fe3O4@CuSiO3 nanorattles with different aspect ratios was investigated. Results demonstrated that the ellipsoidal nanorattles with the aspect ratio of 3-4 exhibited about 20% enhancement of microwave absorption intensity compared with spherical Fe3O4@CuSiO3. Generally, as the aspect ratio increased from 2.0 to 3.5, the microwave absorption peak was enhanced monotonously from -20 dB to -30 dB. It was found that the ellipsoidal nanorattles with larger aspect ratio exhibited higher coercivity and double resonance peaks of the real part of complex permittivity, resulting in the improvement of microwave absorption performance. Our research gives insights into the understanding of the anisotropic effect of nanorattles on microwave absorption performance.

Microwave absorption properties of core double-shell FeCo/C/BaTiO₃ nanocomposites

Microwave absorption properties of core double-shell FeCo/C/(x)BaTiO₃ nanocomposites were investigated in the 1-18 GHz frequency range. High resolution transmission electron microscopy studies reveal the core double-shell type nanocomposite with FeCo nanoparticles as the center, while carbon and BaTiO₃ are the inside and the outside shells, respectively. Enhanced relative permittivity made the core double-shell FeCo/C/(x)BaTiO₃ nanocomposites with better electromagnetic impedance matching than that of a FeCo/C and BaTiO₃ mixture. Reflection loss (RL) values of FeCo/C/(20 wt%)BaTiO₃-paraffin composite are almost double those of the FeCo/C-paraffin composite at the absorbent thickness from 2 to 7.5 mm due to enhanced interfacial effects. The RL value of the FeCo/C/(20 wt%)BaTiO₃-paraffin composite is -41.7 dB at 11.3 GHz at the absorbent thickness of 2 mm and a broad absorption bandwidth of 5.1 GHz (RL values exceeding -10 dB) covers the 9.4-14.5 GHz frequency range.

Synthesis and microwave absorption properties of yolk-shell microspheres with magnetic iron oxide cores and hierarchical copper silicate shells

Yolk-shell microspheres with magnetic Fe3O4 cores and hierarchical copper silicate shells have been successfully synthesized by combining the versatile sol-gel process and hydrothermal reaction. Various yolk-shell microspheres with different core size and shell thickness can be readily synthesized by varying the experimental conditions. Compared to pure Fe3O4, the as-synthesized yolk-shell microspheres exhibit significantly enhanced microwave absorption properties in terms of both the maximum reflection loss value and the absorption bandwidth. The maximum reflection loss value of these yolk-shell microspheres can reach -23.5 dB at 7 GHz with a thickness of 2 mm, and the absorption bandwidths with reflection loss lower than -10 dB are up to 10.4 GHz. Owing to the large specific surface area, high porosity, and synergistic effect of both the magnetic Fe3O4 cores and hierarchical copper silicate shells, these unique yolk-shell microspheres may have the potential as high-efficient absorbers for microwave absorption applications.

Microwave absorption enhancement of multifunctional composite microspheres with spinel Fe3 O4 Cores and Anatase TiO2 shells

Multifunctional composite microspheres with spinel Fe(3)O(4) cores and anatase TiO(2) shells (Fe(3)O(4)@TiO(2)) are synthesized by combining a solvothermal reaction and calcination process. The size, morphology, microstructure, phase purity, and magnetic properties are characterized by scanning electron microscopy, transmission electron microscopy (TEM), high-resolution TEM, selected-area electron diffraction, electron energy loss spectroscopy, powder X-ray diffraction, and superconducting quantum interference device magnetometry. The results show that the as-synthesized microspheres have a unique morphology, uniform size, good crystallinity, favorable superparamagnetism, and high magnetization. By varying the experimental conditions such as Fe(3)O(4) size and concentration, microspheres with different core sizes and shell thickneses can be readily synthesized. Furthermore, the microwave absorption properties of these microspheres are investigated in terms of complex permittivity and permeability. By integration of the chemical composition and unique structure, the Fe(3)O(4)@TiO(2) microspheres possess lower reflection loss and a wider absorption frequency range than pure Fe(3)O(4). Moreover, the electromagnetic data demonstrate that Fe(3)O(4@TiO(2) microspheres with thicker TiO(2) shells exhibit significantly enhanced microwave absorption properties compared to those with thinner TiO(2) shells, which may result from effective complementarities between dielectric loss and magnetic loss. All the results indicate that these Fe(3)O(4)@TiO(2) microspheres may be attractive candidate materials for microwave absorption applications.