The mesoporous hydroxyapatite （HA） was synthesized by hydrothermal method utilizing cationic surfactant cetyltrimethylammonium bromide （CTAB） as template. The crystalline phase, morphology and porous structure wer...The mesoporous hydroxyapatite （HA） was synthesized by hydrothermal method utilizing cationic surfactant cetyltrimethylammonium bromide （CTAB） as template. The crystalline phase, morphology and porous structure were characterized respectively by different detecting techniques. The results reveal that the particles are highly crystalline hydroxyapatite phase. The surfactant has little influence on the morphology of the crystals, but affects the porous structure obviously. The sample without CTAB has a low surface area not exceeding 33 m^2/g, and no distinct pores can be observed by TEM. While the samples obtained with the surfactant get better parameters. Numerous open-ended pores centered at 2-7 nm spread unequally on the surface of the hydroxyapatite nanorods. The N2 adsorption-desorption experiments show type IV isotherms with distinct hysteresis loops, illustrating the presence of mesoporous structure. When the mole ratio of CTAB to HA is 1：2, the sample has the largest surface area of 97.1 m^2/g and pore volume of 0.466 cm^3/g.展开更多
CuS microcrystals were successfully prepared through a mild solvothermal reaction in ethylene glycol （EG） with the assistance of cationic surfactant cetyltrimethylammonium bromide （CTAB）. An interesting morphology...CuS microcrystals were successfully prepared through a mild solvothermal reaction in ethylene glycol （EG） with the assistance of cationic surfactant cetyltrimethylammonium bromide （CTAB）. An interesting morphology evolution from flower-like microspheres to hollow microspheres, and finally to smooth nanoflakes was observed when increasing the amount of CTAB. The products were characterized by X-ray diffraction （XRD）, scanning electron microscopy （SEM）, transmission electron microscopy （TEM）, and UV-vis spectroscopy. It was found that the amount of CTAB played an important role in determining the morphology of the CuS microcrystals. Electrical measurement reveals that the as-prepared CuS microspheres were of high conductivity, which might favor their device applications. It is expected that CuS microcrystals with controlled morphologies and structures will have important applications in solar cells. This simple but effective method could also be extended to the controlled growth of other inorganic microcrystals.展开更多
基金Projects(51102285,81170912)supported by the National Natural Science Foundation of ChinaProject supported by the Open Foundation of State Key Laboratory of Powder Metallurgy,China
文摘The mesoporous hydroxyapatite （HA） was synthesized by hydrothermal method utilizing cationic surfactant cetyltrimethylammonium bromide （CTAB） as template. The crystalline phase, morphology and porous structure were characterized respectively by different detecting techniques. The results reveal that the particles are highly crystalline hydroxyapatite phase. The surfactant has little influence on the morphology of the crystals, but affects the porous structure obviously. The sample without CTAB has a low surface area not exceeding 33 m^2/g, and no distinct pores can be observed by TEM. While the samples obtained with the surfactant get better parameters. Numerous open-ended pores centered at 2-7 nm spread unequally on the surface of the hydroxyapatite nanorods. The N2 adsorption-desorption experiments show type IV isotherms with distinct hysteresis loops, illustrating the presence of mesoporous structure. When the mole ratio of CTAB to HA is 1：2, the sample has the largest surface area of 97.1 m^2/g and pore volume of 0.466 cm^3/g.
基金supported by the National Natural Science Foundation of China(Nos.20901021,51172151,61106010 and21101051)the National Basic Research Program of China(Nos.2010CB301802 and 2012CB932400)+1 种基金the Natural Science Foundation of Anhui Province of China(No.11040606Q26)the Fundamental Research Funds for the Central Universities(Nos.2013HGXJ0195 and 2013HGCH0012)
文摘CuS microcrystals were successfully prepared through a mild solvothermal reaction in ethylene glycol （EG） with the assistance of cationic surfactant cetyltrimethylammonium bromide （CTAB）. An interesting morphology evolution from flower-like microspheres to hollow microspheres, and finally to smooth nanoflakes was observed when increasing the amount of CTAB. The products were characterized by X-ray diffraction （XRD）, scanning electron microscopy （SEM）, transmission electron microscopy （TEM）, and UV-vis spectroscopy. It was found that the amount of CTAB played an important role in determining the morphology of the CuS microcrystals. Electrical measurement reveals that the as-prepared CuS microspheres were of high conductivity, which might favor their device applications. It is expected that CuS microcrystals with controlled morphologies and structures will have important applications in solar cells. This simple but effective method could also be extended to the controlled growth of other inorganic microcrystals.
