In this study, we have established a facile method to synthesize functional hollow carbon spheres with large hollow interior, which can act as active colloidal catalysts. The method includes the following steps: firs...In this study, we have established a facile method to synthesize functional hollow carbon spheres with large hollow interior, which can act as active colloidal catalysts. The method includes the following steps: first, hollow polymer spheres with large hollow interior were prepared using sodium oleate as the hollow core generator, and 2,4-dihydroxybenzoic acid and hexamethylene tetramine (HMT) as the polymer precursors under hydrothermal conditions; Fe3+ or Ag+ cations were then introduced into the as-prepared hollow polymer spheres through the carboxyl groups; finally, the hollow polymer spheres can be pseudomorphically converted to hollow carbon spheres during pyrolysis process, meanwhile iron or silver nanoparticles can also be formed in the carbon shell simultaneously. The structures of the obtained functional hollow carbon spheres were characterized by TEM, XRD, and TG. As an example, Ag-doped hollow carbon spheres were used as colloid catalysts which showed high catalytic activity in 4-nitrophenol reduction reaction.展开更多
The phase states of the catalytic system of FeCl3-Al(i-Bu)3-pyridine are studied in the paper by means of the Tyndall effect, electron microscopy and super-filtration. It is found that the catalyst dispersing in the...The phase states of the catalytic system of FeCl3-Al(i-Bu)3-pyridine are studied in the paper by means of the Tyndall effect, electron microscopy and super-filtration. It is found that the catalyst dispersing in the butadienehydrogasoline solution exists in small particles and the size of particle is 30 nm or so in diameter. The catalyst belongs to a multi-phase catalytic system. The active center of catalyst lies on the surface of nanometer particles, which are amorphous. The ratios of different components of catalyst affect the formation of the particles. With the optimum ratio, nanometer particles, which disperse more uniformly and are of highly catalytic activity, can be obtained.展开更多
基金supported by NSFC (No. 20873014 and 21073026)the Program for New Century Excellent Talents in University of China (NCET-09-0254)
文摘In this study, we have established a facile method to synthesize functional hollow carbon spheres with large hollow interior, which can act as active colloidal catalysts. The method includes the following steps: first, hollow polymer spheres with large hollow interior were prepared using sodium oleate as the hollow core generator, and 2,4-dihydroxybenzoic acid and hexamethylene tetramine (HMT) as the polymer precursors under hydrothermal conditions; Fe3+ or Ag+ cations were then introduced into the as-prepared hollow polymer spheres through the carboxyl groups; finally, the hollow polymer spheres can be pseudomorphically converted to hollow carbon spheres during pyrolysis process, meanwhile iron or silver nanoparticles can also be formed in the carbon shell simultaneously. The structures of the obtained functional hollow carbon spheres were characterized by TEM, XRD, and TG. As an example, Ag-doped hollow carbon spheres were used as colloid catalysts which showed high catalytic activity in 4-nitrophenol reduction reaction.
文摘The phase states of the catalytic system of FeCl3-Al(i-Bu)3-pyridine are studied in the paper by means of the Tyndall effect, electron microscopy and super-filtration. It is found that the catalyst dispersing in the butadienehydrogasoline solution exists in small particles and the size of particle is 30 nm or so in diameter. The catalyst belongs to a multi-phase catalytic system. The active center of catalyst lies on the surface of nanometer particles, which are amorphous. The ratios of different components of catalyst affect the formation of the particles. With the optimum ratio, nanometer particles, which disperse more uniformly and are of highly catalytic activity, can be obtained.