The auto-evolved ultrafine copper powders were synlhesized via a novel electrodeposition route performed by ultrasonic dispersion of the electrolyte. The properties of the samples obtained were characterized by X-ray ...The auto-evolved ultrafine copper powders were synlhesized via a novel electrodeposition route performed by ultrasonic dispersion of the electrolyte. The properties of the samples obtained were characterized by X-ray powder diffractometry （XRD）, transmission electron microscopy （TEM）, scanning electron microscopy （SEM） and laser size distribution analyzer （SL） respectively. The formation mechanisms of the powders and the efficiency of the elctrodeposition were discussed. The results show that the as-prepared powders are high-purity copper nanoparticles with the fcc structure taking a mixture of fishbone-like and irregular shapes When the concentration of Cu^2＋ increases from 0.03 to 0.09 mol/L, the average size of copper particles increases from 0.92 to 1.80 μm, and current efficiency of electrodeposition linearly changes from 66.5% to 91.3%.展开更多
Microsized single-crystalline Co3O4 has been synthesized by high-temperature hydrolysis of CoCD2H20 at 600℃. The samples were characterized by powder X-ray diffraction （XRD）, scanning electron microscopy （SEM） an...Microsized single-crystalline Co3O4 has been synthesized by high-temperature hydrolysis of CoCD2H20 at 600℃. The samples were characterized by powder X-ray diffraction （XRD）, scanning electron microscopy （SEM） and transmission electron microscopy （TEM）. The results reveal that the as-prepared powders are microsized single-crystalline CO3O4 with cubic spinel structure. An increase in the high-temperature hydrolysis time results in the evolution of particle shapes from cube to quasi-sphere, and then to octahedron. The effect of NaCl additive on the surface morphologies of Co3O4 particles was experimentally investigated. The results indicate that the NaCl additive acts as an inert disperse phase in the high-temperature hydrolysis, and prevents the aggregation of Co3O4 particles effectively.展开更多
基金Project(08JJ3104) support by Hunan Provincial Natural Science Foundation of China
文摘The auto-evolved ultrafine copper powders were synlhesized via a novel electrodeposition route performed by ultrasonic dispersion of the electrolyte. The properties of the samples obtained were characterized by X-ray powder diffractometry （XRD）, transmission electron microscopy （TEM）, scanning electron microscopy （SEM） and laser size distribution analyzer （SL） respectively. The formation mechanisms of the powders and the efficiency of the elctrodeposition were discussed. The results show that the as-prepared powders are high-purity copper nanoparticles with the fcc structure taking a mixture of fishbone-like and irregular shapes When the concentration of Cu^2＋ increases from 0.03 to 0.09 mol/L, the average size of copper particles increases from 0.92 to 1.80 μm, and current efficiency of electrodeposition linearly changes from 66.5% to 91.3%.
基金Project(50704038) supported by the National Natural Science Foundation of ChinaProject(108170) supported by the Key Foundation of Ministry of Education,China
文摘Microsized single-crystalline Co3O4 has been synthesized by high-temperature hydrolysis of CoCD2H20 at 600℃. The samples were characterized by powder X-ray diffraction （XRD）, scanning electron microscopy （SEM） and transmission electron microscopy （TEM）. The results reveal that the as-prepared powders are microsized single-crystalline CO3O4 with cubic spinel structure. An increase in the high-temperature hydrolysis time results in the evolution of particle shapes from cube to quasi-sphere, and then to octahedron. The effect of NaCl additive on the surface morphologies of Co3O4 particles was experimentally investigated. The results indicate that the NaCl additive acts as an inert disperse phase in the high-temperature hydrolysis, and prevents the aggregation of Co3O4 particles effectively.
