A stable δ- and β-bismuth trioxide was prepared at room temperature by vacuum vapor-phase oxidation. The average crystal size of products was 14.6 nm (by XRD), the d(0.5) value was in the range from 62 nm to 69 nm, ...A stable δ- and β-bismuth trioxide was prepared at room temperature by vacuum vapor-phase oxidation. The average crystal size of products was 14.6 nm (by XRD), the d(0.5) value was in the range from 62 nm to 69 nm, and geometric standard deviation(GSD) was from 1.42 to 1.64. The results show that δ-Bi2O3 is formed when quenching rates is rapid and β-Bi2O3 is formed when it is slow. The size of grains increases with rising reaction temperature, flow rate of carrier gas, residual pressure of system and longer growing time of grains.展开更多
基金Project(03SSY4056) supported by the Bureau of Science and Technology of Hunan Province, China Project(04C034) supported by the Bureau of Education of Hunan Province, China
文摘A stable δ- and β-bismuth trioxide was prepared at room temperature by vacuum vapor-phase oxidation. The average crystal size of products was 14.6 nm (by XRD), the d(0.5) value was in the range from 62 nm to 69 nm, and geometric standard deviation(GSD) was from 1.42 to 1.64. The results show that δ-Bi2O3 is formed when quenching rates is rapid and β-Bi2O3 is formed when it is slow. The size of grains increases with rising reaction temperature, flow rate of carrier gas, residual pressure of system and longer growing time of grains.
