Li 4 SiO 4 was obtained by using quartz powder of different particle sizes (75−180 μm, 45−75 μm, 38−45 μm, and <38 μm) and Li 2 CO 3 as raw materials through a solid-state reaction at 720 °C. X-ray diffraction (XRD), scanning electron microscopy (SEM), and differential thermal analysis and thermogravimetry (DTA/TG) were used to examine the sintering behavior and properties of the samples. The results indicated that when the particle size of the quartz powder decreased, the solid-state reaction performed more completely, the content of the Li 4 SiO 4 phase increased, and the size of the grain agglomerates decreased gradually. The enhanced chemical reactivity of the quartz powder with Li 2 CO 3 and the shortened diffusion distance as the quartz size decreases are helpful to the formation of the Li 4 SiO 4 phase. The sorption analysis revealed that the samples synthesized using the quartz powder with smaller particle sizes experienced a more rapid absorption−desorption process with a higher absorption efficiency.

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A zinc oxide (ZnO) nanoarray (rod‐like nanostructure) was successfully synthesized through a low‐temperature aqueous solution and microwave‐assisted synthesis using zinc nitrate hexahydrate (Zn(NO3)2·6H2O) and hexamethylenetetramine (HMTA) as raw materials, and using FTO glass as substrate. The effects of parameters in the preparation process, such as solution concentration, reaction temperature and microwave power, on the morphology and microstructure of ZnO nanoarray were studied. Phase structure and morphology of the products were characterized by X‐ray diffraction (XRD) and scanning electron microscopy (SEM), respectively. The results indicated that hexagonal wurtzite structure ZnO nanoarray with good crystallization could be prepared through a low‐temperature solution method. When the concentration of the mixed solution was 0.05 M, the reaction temperature was 95 °C, and the reaction time was 4 h, high‐density ZnO regular nanorods of 200 nm diameter were obtained. A possible mechanism with different synthesis methods and the influence of microwave processing are also proposed in this paper.

Well-dispersed carbon-doped ZnSn(OH) 6 submicrocubes were successfully synthesized through a facile and economical hydrothermal method at 433K, which used green chemical glucose (C 6 H 12 O 6 ) as the carbon-doping source. Photocatalytic activity of the as-synthesized C-doped ZnSn(OH) 6 was evaluated by studying photocatalytic decomposition of methylene blue (MB) in aqueous solution under visible light irradiation(ࣙ 400 nm). The results show that carbondoped ZnSn(OH) 6 photocatalysts exhibited higher photocatalytic performance as compared to pure ZnSn(OH) 6 . 1.0 wt% C-doped ZnSn(OH) 6 photocatalyst exhibited obviously higher photocatalytic activity that of pure ZnSn(OH) 6 or other C-ZnSn(OH) 6 catalysts under the same condition. The enhanced photocatalytic degradation of MB could be attributed to the doping of carbon and the possible mechanism for high photocatalytic activity of C-doped ZnSn(OH) 6 was discussed.

ZnO nanostructures with different morphologies were prepared in microemulsions with ZnSO4 and ammonia as raw materials. The effects of microemulsion types, concentration of reactants, W values, co‐surfactants, surfactants, oil phases and calcination temperatures were systematically studied. The products were characterized by X‐ray diffraction (XRD), differential scanning calorimetry and thermogravimetry (DSC‐TG), transmission electron microscopy (TEM), high‐resolution TEM (HRTEM), and photoluminescence (PL) spectrum. Results show that ZnO nanoparticles were obtained in water‐in‐oil microemulsions while ZnO nanorods are gained in bicontinuous microemulsions. Water‐in‐oil microemulsions and long carbon chains of surfactants can prevent the preferential growth of ZnO. The particle size of the products increased with the increase of W values, calcination temperatures and the concentration of reactants but decreased with the increase of the carbon chain length of surfactants, co‐surfactants and oil phases. PL spectrums show that the UV emission peak weakened and visible emission peak increased with the decrease of particle size. Meanwhile, the PL spectrums have a little red‐shifted.

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