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One-dimensional (1D) single crystalline CdS nanostructures have been successfully synthesized via a diphenylthiocarbazone-assisted solvothermal route. The results revealed that the microstructure and optical absorption properties of 1D CdS nanostructures were temperature and time dependent owing to thermodynamically and kinetically controlled growth. Single crystalline CdS nanowires with a diameter of 80 nm and length of 20 μm were synthesized at 180°C for 96 h. At moderate temperature (180°C), the morphology of the products transformed from irregular short rods to uniform long rods as the reaction time prolonging in a kinetically controlled growth regime. Only nanorods were obtained at a temperature as low as 120°C even extending reaction time to 260 h due to thermodynamic limited growth. At high temperature (250°C in this system), the products were nanowires with larger diameter but lower aspect ratio since the growth rates on both lateral and axial directions were accelerated. Moreover, the optical absorption spectra revealed that the CdS nanowires showed a blue shift compared with bulk CdS. Two optical absorption peaks appeared due to the nanometer effect in the radial and lengthwise directions of CdS nanowires. The growth mechanism of 1D CdS nanostructures was discussed.

In this paper, regularly shaped AlF₃ particles with cubic structure were successfully synthesized via a solvothermal route. The as-prepared products were characterized by X-ray powder diffraction (XRD), energy-dispersive spectroscopy (EDS), scanning electron microscopy (SEM) and transmission electron microscopy (TEM). The experimental results indicated that reaction temperature and time have significant effects on the morphology of the as-prepared products. A possible formation process has also been investigated on the basis of a series of XRD and SEM studies of the product obtained at different conditions. This well-controlled synthesis approach may be extended to fabricate other metal fluoride materials.

TiO₂@MWCNT heterostructure containing single one carbon nanotube has been successfully prepared via solvothermal method. X-ray diffration (XRD) analysis shows that TiO₂ nanocrystals only contain highly crystallized tetragonal anatase phase. Interestingly, scanning electron microscope (SEM) and transmission electron microscope (TEM) results show that most of the TiO₂ nanocrystals are perpendicular to the surface of multi-walled carbon nanotube (MWCNT) and only single one carbon nanotube is coated by TiO₂ crystals. The electromagnetic (EM) characteristics are investigated at 0.5–18.0 GHz range. The EM properties show that both the permittivity and the permeability present a typical resonance behavior at 11.0 GHz and 12.0 GHz, respectively. Besides, the TiO₂@MWCNT heterostructures exhibit a broadband absorption throughout the whole Ku wave bands (12.0–18.0 GHz). Interestingly, the reflection loss (RL) of the TiO₂@MWCNT heterostructures change slightly as the thickness of the heterostructures increase from 3.0 mm to 5.0 mm in the 8.0–13.0 GHz range.

In this work, reduced graphene oxide (RGO)/ferroferric oxide (RGO/Fe₃O₄) hybrid composite was successfully fabricated by a facile one-step solvothermal method. The structure, chemical composition, morphology and magnetic properties of the samples were investigated in detail. Fe₃O₄ microspheres with an average diameter of 250nm were uniformly anchored on the surface of the RGO sheets without large aggregation. Moreover, the results demonstrated that the hybrid composite exhibited obviously enhanced microwave absorption properties compared with the pure Fe₃O₄ microspheres. The minimum reflection loss (RL) of the hybrid composite reached $-$36.8dB at 17.2GHz with a thickness of 5.0mm and its effective absorption bandwidth (lower than $-$10dB) was 3.9GHz with a thickness of 2.5mm. Significantly, the hybrid composite exhibited a dual-waveband absorption characteristic covering the C and Ku bands. Besides, the relationship between the matching thickness and peak frequency was reasonably explained according to the quarter-wavelength matching theory. Therefore, the obtained composite was a promising candidate for application in microwave absorption.

In this work, we designed a simple substrate-immersed solvothermal route for the one-step synthesis of novel ordered SiO₂/Ag arrays, employing SiO₂ colloidal crystals as templates and alcohol as reducing agent. The Ag nanoparticles were uniformly deposited in situ onto SiO₂ colloidal crystals, which exhibited high surface enhanced Raman spectroscopy (SERS) activity and uniform SERS intensity. It was found that ordered SiO₂/Ag arrays could rapidly scavenge the absorbed-Nile blue A (NBA) molecules from the surfaces with the assistance of H₂O₂, while the SERS signals of NBA decreased sharply and almost completely disappeared within four minutes. This can be attributed to the superior catalytic activity of Ag nanoparticles. After five times of re-immersion and re-absorbing process of NBA, the substrates could still keep $\sim$ 74.8% SERS intensity versus the original. The high activity and durability of the as-prepared SiO₂/Ag SERS substrate endow them as a promising candidate for trace detection.

The olivine LiFePO₄ with various morphologies and different growth lattice planes was prepared by a controllable hydrothermal method with changing precursor concentration and using phytic acid as phosphorus source. The microstructure, crystal orientation and electrochemical performance of the prepared samples were characterized by X-ray diffraction (XRD), scanning electron microscopy (SEM), high-resolution transmission electron microscopy (HR-TEM) and charge–discharge tests. The results show that the morphologies of all samples change from spindle-like to hierarchical plate-like and then to long plate-like shape, and the main exposed facets transform from (100) to (001). This indicates that the precursor concentration and phytic acid play important roles in exposing facets and controlling the morphology of LiFePO₄. In order to illustrate these phenomena, a reasonable assembly process is provided and the formation is explained. Li ion diffusion coefficient along [100] and [001] directions was calculated by using electrochemical impedance spectroscopy (EIS). The results show that the diffusion coefficient of (100) facet is higher than that of (001) facet, indicating a good electrochemical performance for (100) facet. In addition, the capacity test is carried out, which also confirms the above results. With the precursor concentration of 0.5M, the obtained LiFePO₄ with self-assembled hierarchical structure, smaller size and (100) facet shows the best electrochemical performance: 162.1mAh/g at 0.1C and 112.4mAh/g at 10C. Using phytic acid as phosphorus source and controlling precursor concentration to prepare high performance LiFePO₄ open up a new prospect for the production of cathode materials for lithium ion batteries.