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Pt nanoparticles decorated with rose-like Bi2O2CO3 configurations were synthesized via a simple photoreduction method at room temperature. The structure, morphology, optical and electronic properties, and photocatalytic performance of the as-prepared materials were characterized. Compared to pure Bi2O2CO3, the Pt/Bi2O2CO3 photocatalysts show better performance in decomposing RhB, BPA and OTC under visible light (λ > 420 nm). The enhanced photocatalytic activity of Pt/Bi2O2CO3 could be attributed to the modification in light absorption (λ > 420 nm) charge migration and the separation of photo-generated electrons (e−) and holes (h+). Free radical trapping experiments demonstrated that the main active species of the catalytic reaction are different in decomposing RhB and BPA.

The improvement of high reflection loss and broad frequency bandwidth for electromagnetic wave absorption materials is a long-term effort. The superb micro-structures of the absorber have significant impact on increasing reflection loss and broadening frequency bandwidth. Herein, we prepared 3D graphene by chemical vapor deposition and then 3D graphene/pine needle-like iron nano-acicular whisker composites were in situ synthesized by an electrochemical deposition process under an electric field using 3D graphene as substrate. The nano-acicular whiskers show different sizes and the mean diameter of the individual iron nano-acicular whiskers was about 150 nm. The saturation magnetization (MS) of the 3D graphene/iron nano-acicular whisker composite was about 42.65 emu g−1 and the coercivity (Hc) was 143 Oe, and it shows good magnetic properties. In the frequency range of 2–18 GHz, the reflection loss value of the graphene/iron nano-acicular whisker composites with a thickness of 2 mm could reach −12.81 dB at 10.95 GHz and the effective absorption bandwidth below −10 dB was 2.16 GHz. The nano-acicular whiskers could effectively improve the electromagnetic wave absorbing properties. The results suggested that the as-prepared graphene/iron nano-acicular whisker nanocomposite showed great potential applications as a new absorber material.

The development of high reflection loss and broad frequency bandwidth for electromagnetic wave absorbing materials has been pursued for a long time. Constructing a rational microstructure of an absorber will have significant impact on reflection loss increase and frequency bandwidth broadening. Herein, we successfully prepare a sandwich microstructured graphene/BaFe12O19 nanocomposite by an in situ auto-combustion method. Compared to pure BaFe12O19, the sandwich microstructured graphene/BaFe12O19 showed better electromagnetic wave absorbing properties. Furthermore, the sandwich microstructured graphene/Ba0.8La0.2Fe12O19 nanocomposite was prepared with La-doped BaFe12O19 using the same method. The obtained graphene/Ba0.8La0.2Fe12O19 nanocomposite exhibited a saturation magnetization of 26.55 emu g−1 at room temperature and exhibited excellent magnetic performance. The maximum reflection loss of the sandwich microstructured graphene/Ba0.8La0.2Fe12O19 nanocomposite with a thickness of 1 mm could reach up to −40.26 dB, and a frequency bandwidth value below −10 dB was observed up to 3.87 GHz within the frequency range of 2–18 GHz.

3D dendritic Fe2O3 nanoparticles wrapped with carbon (denoted as 3DD-Fe2O3@C hereafter) were synthesized. It is found that the 3DD-Fe2O3@C is composed of α-Fe2O3 and amorphous carbon. As an anode material for lithium ion batteries (LIBs), it exhibits an excellent discharge/charge capacity (982 mA h g−1 and 971 mA h g−1 after 100 cycles at a rate of 100 mA g−1), and good cyclic stability and rate capability.

The 3D interlinked amorphous carbon nanotube (ACNT)/reduced graphene oxide (RGO)/BaFe12O19 (BF) composite was directly prepared by a self-propagation combustion process. The RGO was synthesized in situ through the massive heat release during the auto-combustion reaction. The interlinked ACNTs and graphene as well as BF formed the conductive networks for improving the dielectric and magnetic loss. The reflection loss peak of ACNT/RGO/BF composite was −19.03 dB at 11.04 GHz in the frequency range of 2–18 GHz. The frequency bandwidth of the reflection loss below −10 dB was 3.8 GHz. The 3D interlinked ACNT-RGO structure, which was composed of dense intertwined ACNT and graphene with quantities of dihedral angles, could consume incident waves via multiple reflections inside the 3D structures. The high conductivity of 3D interlinked ACNT/RGO networks would lead to energy dissipation in the form of heat through molecular friction and dielectric loss.

Highly vertically aligned carbon nanotube arrays grown on the surface of pure titanium plates by chemical vapor deposition serve as substrates for electrodepositing polyaniline, thus fabricating three-dimensional carbon nanotube/polyaniline composites. In addition, X-ray diffraction and Raman spectroscopy are applied to investigate the structures of the as-prepared hybrids. Morphological analysis of the nanotube/polyaniline composites is performed by high resolution SEM and transmission electron microscopy. The combination of the three-dimensional carbon nanotube architecture and conducting polyaniline surprisingly generates a synergistic effect on electrochemical performance which is particularly important. Consequently, the vertically aligned carbon nanotube/polyaniline hybrids exhibit excellent characteristics in terms of specific capacitance (752.5 F g−1) and power density (5364 W kg−1) at a scanning rate of 100 mV s−1. Furthermore, the capacity retention can reach over 82% (after 10 000 cycles). This work highlights the critical role of the introduction of vertically laid carbon nanotubes with highly conducting polyaniline in improving the performance of supercapacitors.

Pt nanoparticles decorated with rose-like Bi