Porous tetragonal BaTiO 3 ceramic was successfully prepared by a combination of hydrothermal and low-temperature-sintering method.The hollow TiO2@BaCO 3 as the sintering precursor was synthesized via a simple hydrothermal method,and then porous BaTiO 3 was generated by calcining the hollow TiO2@BaCO 3 precursor at 900 ℃ without additive.The hollow TiO2@BaCO 3 structure plays two important roles in the preparing of the porous BaTiO 3 ceramic.First,the TiO2@BaCO 3 hollow structure provides high surface areas and increases the contact points between BaCO 3 and TiO2,which can reduce the sintering temperature of the BaTiO 3 ceramic.Second,the cavity of the ordered arranged TiO2@BaCO 3 hollow sphere shows important influence on the porous structure,and the pore size of the as-prepared porous BaTiO 3 ceramic can be tuned from several nanometers to hundreds nanomters by changing the sintering temperature.The formation mechanism of the porous BaTiO 3 ceramic was proposed.
LI YangLIU HuLIU FaJiaLI ChaoRongCHEN BenYongDONG WenJun
This review highlights the recent research progress on inorganic solid state energy materials in China,from synthesis and fundamental properties to their applications.It describes the significant contributions of Chinese scholars in the field of inorganic solid state chemistry and energy materials including green catalysts,fuel cells,lithium batteries,solar cells,hydrogen storage materials,thermoelectric materials,luminescent materials and superconductors,and then outlines the ongoing rapid progress of novel inorganic solid state materials and the development of reliable and reproducible preparation methods for inorganic solid state materials in China.Finally,we conclude the paper by considering future developments of inorganic solid state chemistry and energy materials in China.
Ball in cage structures of cobalt sulfide have been successfully prepared by a facile one-pot hydrothermal synthesis approach employing Co(NO3)2·6H2O as the cobalt source and S=C(NH2)2 as the sulfur source. The effects of the reaction parameters (volume ratio of distilled water to ethanol, reaction time and reaction temperature) on the morphology and size of the CoS structures were investigated. The synthesized product was characterized by X-ray diffraction, scanning electron microscopy and transmission electron microscopy. It has been confirmed that the volume ratio of distilled water to ethanol played a key role in the formation of the ball in cage structures, and the formation mechanism of the CoS ball in cage structures was also proposed. The electrochemical capacitance performances of the CoS products were studied, and the CoS ball in cage structures show excellent energy storage characteristics.
This paper reviews the recent research progress in the hetero-nanostructure of silver nanoparticles on MOx (M=Mo, Ti and Si). It describes the general synthesis of hetero-nanostructure of silver nanoparticles on MOx, and then outlines the interesting catalytic and sensing properties found in these hetero-nanostructures of silver nanoparticles on MOx.
