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Flexible Fe3O4/SiO2/PVDF nanocomposites are prepared by embedding porous Fe3O4/SiO2 core/shell nanorods in polyvinylidene fluoride (PVDF) matrix. The nanocomposite with filler content of 40 wt% shows excellent microwave absorption performance over 2−18 GHz.

Ce3+-doped yttrium aluminum garnet (YAG:Ce) nanocrystals were successfully synthesized via a facile sol-gel method. Multiple characterization techniques were employed to study the structure, morphology, composition and photoluminescence properties of YAG:Ce nanophosphors. The YAG:Ce0.0055 sintered at 1030 °C exhibited a typical 5d1-4f1 emission band with the maximum peak located at 525 nm, and owned a short fluorescence lifetime τ1 (~28 ns) and a long fluorescence lifetime τ2 (~94 ns). Calcination temperature and Ce3+ doping concentration have significant effects on the photoluminescence properties of the YAG:Ce nanophosphors. The emission intensity was enhanced as the calcination temperature increased from 830 to 1030 °C, but decreased dramatically with the increase of Ce3+ doping concentration from 0.55 to 5.50 at.% due to the concentration quenching. By optimizing the synthesized condition, the strongest photoluminescence emission intensity was achieved at 1030 °C with Ce3+ concentration of 0.55 at.%.

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Anisotropic Fe3O4 nanoparticle and a series of its graphene composites have been successfully prepared as high-frequency absorbers. The crystal structure, morphology and magnetic property of the samples were detailed characterized through X-ray diffractometer (XRD), transmission electron microscopy (TEM) and vibrating sample magnetometer (VSM). The high-frequency absorbing performance of the composites is evaluated within 2.0–18.0 GHz. Combining reduced graphene oxide (RGO) to Fe3O4 helps to adjust the permittivity and permeability of the composite, balance the dielectric loss and magnetic loss, consequently improve the absorbing performance in view of the impedance matching characteristic. The optimal reflection loss of the pure Fe3O4 sample reaches −38.1 dB with a thickness of 1.7 mm, and it increases to −65.1 dB for the sample grafted with 3 wt.% RGO. The addition of proper content of RGO both improves the reflection loss and expands the absorbing bandwidth. This work not only opens a new method and an idea for tuning the electromagnetic properties and enhancing the capacity of high-efficient absorbers, but also broadens the application of such kinds of lightweight absorbing materials frameworks.

Hierarchical NiCo2O4/Co3O4/NiO composite was fabricated through a facile hydrothermal method, followed by a post-annealing treatment.

Porous TiNi shape-memory alloys (SMAs) have been successfully fabricated by three different processes, including capsule-free hot isostatic pressing (CF-HIP), conventional sintering (CS), and self-propagating high-temperature synthesis (SHS). A systematically comparative investigation was made on their phase transformation behaviors, mechanical properties, superelasticity, and damping performance. The results show that the CF-HIP process is the best among these methods. By controlling the processing parameters of CF-HIP, the porous TiNi SMA shows the expected pore characteristics, such as a round pore shape and a homogeneous pore distribution. The porous TiNi SMA produced by CF-HIP also exhibits good properties, such as superior superelasticity (up to 4 pct recoverable strain), a flat stress yield plateau, and a high compressive strength, similar to those of the dense TiNi SMAs. In addition, the porous TiNi SMA produced by CF-HIP has a much smaller strain hysteresis, superior damping performance to a porous TiNi SMAs produced with CS, and SHS.

A new octahedral ZnO/ZnFe2O4 heterostructure has been fabricated through a facile surfactant-free solvothermal method followed by thermal treatment. It exhibits a record-high adsorption capacity (up to 4983.0 mg·g−1) of malachite green (MG), which is a potentially harmful dye in prevalence and should be removed from wastewater and other aqueous solutions before discharging into the environment. The octahedral ZnO/ZnFe2O4 heterostructure also demonstrates strong selective adsorption towards MG from two kinds of mixed solutions: MG/methyl orange (MO) and MG/rhodamine B (RhB) mixtures, indicating its promise in water treatment.