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SiC-ZrC composite powders were synthesized by carbothermal reduction method using starch as carbon source, zirconium dioxide as zirconium source, and silica sol as silicon source. The effects of reaction temperature on the phase composition and microstructure of SiC-ZrC composite powders were investigated. The reaction process was thermodynamically analyzed and calculated, and the synthesis mechanism of SiC-ZrC composite powder was analyzed. The synthesized powder samples were characterized and analyzed by X-ray diffraction, scanning electron microscopy, and other testing methods. Results show that the optimum reaction condition for the synthesis of SiC-ZrC composite powders is at 1550 ̊C-1600 ̊C for 1.5 h. High temperature and low pressure are beneficial in conducting the synthesis reaction. The SiC-ZrC composite powders synthesized by calcining at 1550 ̊C and holding for 1.5 h are mainly composed of a certain amount of whiskers, spherical particles, floc particles, and other structures. Moreover, their grain size is small (100-200 nm). The powder samples synthesized at 1600 ̊C produced a larger number of whiskers. The length of the whiskers was mostly 10 μm, the arrangement was complex and irregular, and a diverse microstructure was formed.

SiC-TiC composite powders were synthesised through carbothermal reduction under an argon atmosphere by using silica sol, starch, and TiO₂ as the raw materials. The influences of the starch dosage and holding time on the synthesis of SiC-TiC composite powder are discussed in detail. The samples were characterised using an X-ray diffractometer (XRD), an integrated thermal analyser (TG-DTA), a scanning electron microscope (SEM), and an energy spectrometer (EDS). The results showed that the SiC-TiC composite powders were completely synthesised after holding at 1550 °C for 3 h when the amount of excess starch was 5 wt% and after holding at 1550 °C for 2 h when the amount of excess starch was 10 wt%-20 wt%. The morphological characteristics of the powder samples with 5 wt%-15 wt% excess starch calcined at 1550 °C for 2 h were mainly flake particles, spherical particles, irregularly shaped particles and elongated whiskers. Conversely, no whiskers were found in the powder samples calcined at 1550 °C for 2 h when the amount of excess starch was 20 wt%.

Using aluminum hydroxide (Al(OH)₃) and aluminum nitrate (Al(NO₃)₃.9H₂O) as aluminum sources and highly active glucose (C₆H12O₆) as a carbon source, we synthesized ultrafine AlN powder through carbothermal reduction-nitridation. Then, we explored the effects of aluminum sources, reaction temperature, holding time and other reaction conditions on the phase composition and micromorphology of the synthesized AlN powder. Result showed that AlN powder and different proportions of Al₂O₃-AlN composite powder can be prepared by controlling reaction temperature or holding time. Under the conditions of this experiment, Al(OH)₃ more beneficial as an aluminum source for carbothermal reduction-nitridation than Al(NO₃)₃.9H₂O. The optimum reaction conditions for the synthesis of single-phase AlN powder with Al(OH)₃ as aluminum source were holding time of 3 h and temperature of 1450 °C. The powder sample synthesized under this reaction condition is mainly composed of flaky, short-rod, and irregularly shaped fine particles with sizes ranging from 50 nm to 100 nm.

The thermal stability of the polyethylene (PE) separator is of utmost importance for the safety of lithium-ion batteries. Although the surface coating of PE separator with oxide nanoparticles can improve thermal stability, some serious problems still exist, such as micropore blockage, easy detaching, and introduction of excessive inert substances, which negatively affects the power density, energy density, and safety performance of the battery. In this paper, TiO2 nanorods are used to modify the surface of the PE separator, and multiple analytical techniques (e.g., SEM, DSC, EIS, and LSV) are utilized to investigate the effect of coating amount on the physicochemical properties of the PE separator. The results show that the thermal stability, mechanical properties, and electrochemical properties of the PE separator can be effectively improved via surface coating with TiO2 nanorods, but the degree of improvement is not directly proportional to the coating amount due to the fact that the forces inhibiting micropore deformation (mechanical stretching or thermal contraction) are derived from the interaction of TiO2 nanorods directly "bridging" with the microporous skeleton rather than those indirectly "glued" with the microporous skeleton. Conversely, the introduction of excessive inert coating material could reduce the ionic conductivity, increase the interfacial impedance, and lower the energy density of the battery. The experimental results show that the ceramic separator with a coating amount of ~0.6 mg/cm2 TiO2 nanorods has well-balanced performances: its thermal shrinkage rate is 4.5%, the capacity retention assembled with this separator was 57.1% under 7 C/0.2 C and 82.6% after 100 cycles, respectively. This research may provide a novel approach to overcoming the common disadvantages of current surface-coated separators. [ABSTRACT FROM AUTHOR]

Abstract: SnO2 micro/nano-structured biscuits had been successfully prepared via egg albumin-assisted sol–gel procedure. The typical sample calcined at 900 °C was pure SnO2 with a tetragonal rutile structure, constructed by the numerous pomegranate seed-like irregular nanoparticles in the range of ~100 to ~400 nm. The complexation of egg albumin and tin ions and the bonding characteristics of functional groups had been confirmed. The band gap energy values of samples were apparently higher than the reference value of bulk matter, which could be assigned to a well-known effect that small particles tended to exhibit increased band gaps. It was revealed that with the increase of the calcined temperature the photoluminescence efficiency increased. The sample at 500 °C had the higher photocatalytic activity and the higher mean photo-degradation rate of MO was 88.1 ± 1.2% as compared to other samples, which could be assigned to the lower value of band gap due to the defect levels in the band gap from the impurities formed during the growth and the lower photoluminescence efficiency, beneficial to electrons transfer and reducing the combination of electron and hole, which resulted in better photocatalytic activity.Graphical abstract: [ABSTRACT FROM AUTHOR]

The authors synthesised porous GdF3 :Er3+, Yb3+ –COOH core–shell structured bi‐functional nanoparticles through a one‐step hydrothermal route during which ethylene diamine tetraacetic acid) was bound to the surface of the nanoparticles. It has high up‐conversion emission intensity for monitoring the drug release process and magnetisation saturation value (10.2 emu/g) for drug targeting under foreign magnetic fields. Moreover, porous GdF3 :Er3+, Yb3+ as drug carriers with a high drug‐loading efficiency. cis‐Dichlorodiammineplatinum(II) (cisplatin, CDDP)‐loaded GdF3 :Er3+, Yb3+ nanoparticles (GdF3 :Er3+, Yb3+ –CDDP) were characterised by the Fourier transform infrared spectra, and CDDP was loaded in the form of electrostatic interaction and hydrogen bonds. Compared with CDDP alone, GdF3 :Er3+, Yb3+ –CDDP nanoparticles increase concentration of CDDP in the target site and enhance its anticancer efficiency. Therefore, the as‐prepared GdF3 :Er3+, Yb3+ –COOH nanoparticles allow simultaneous targeted drug delivery and monitoring as promising anti‐cancer theranostic agents. [ABSTRACT FROM AUTHOR]

Highlights: [•] We have synthesized the layered LiNi0.5Mn0.5O2−xF x (0⩽ x ⩽0.04) by hydroxide co-precipitation method. [•] The structure, morphology and electrochemical performance of LiNi0.5Mn0.5O2 are influenced by F doping effect. [•] The cations mixing of pure LiNi0.5Mn0.5O2 decreases and Li+ diffusion coefficient increases with doping F. [•] The reversible capacity of LiNi0.5Mn0.5O1.96F0.04 is 155.0mAhg−1 after 50 cycles at 0.2 C, 0.5 C and 1.0 C ratios between 2.8 and 4.6V. [ABSTRACT FROM AUTHOR]