The metal vapor synthesis technique was employed to prepare Co nanoparticles. The characteristics and properties of the particles were studied by transmission electron microscopy, X-ray diffraction, temperature-progra...The metal vapor synthesis technique was employed to prepare Co nanoparticles. The characteristics and properties of the particles were studied by transmission electron microscopy, X-ray diffraction, temperature-programmed desorption, chemisorption and magnetic measurements. The experimental results showed that the particle size of Co powders depended on the initial Co concentration in the toluene matrix, reaching average crystallite diameter of 1.5 nm for the highest concentration (6.4 at. pct) investigated. The particles with size of 10 nm exist, due to the agglomerates of microcrystallites. The Co particles were surrounded by a thin carbonaceous layer formed due to toluene decomposition on cocondate melt-down and subsequent warming to room temperature. The carbonaceous layer was composed primarily of C1 fragments. The Co powders demonstrated ferromagnetic behavior.展开更多
文摘The metal vapor synthesis technique was employed to prepare Co nanoparticles. The characteristics and properties of the particles were studied by transmission electron microscopy, X-ray diffraction, temperature-programmed desorption, chemisorption and magnetic measurements. The experimental results showed that the particle size of Co powders depended on the initial Co concentration in the toluene matrix, reaching average crystallite diameter of 1.5 nm for the highest concentration (6.4 at. pct) investigated. The particles with size of 10 nm exist, due to the agglomerates of microcrystallites. The Co particles were surrounded by a thin carbonaceous layer formed due to toluene decomposition on cocondate melt-down and subsequent warming to room temperature. The carbonaceous layer was composed primarily of C1 fragments. The Co powders demonstrated ferromagnetic behavior.
