Chemical coprecipitation was used to produce ultrafine and easily sinterable Y2O3-stabilized and （Y2O3,MgO）-stabilized ZrO2 powders. Six precipitation processes for preparation of ZrO2-based ultrafine powders were d...Chemical coprecipitation was used to produce ultrafine and easily sinterable Y2O3-stabilized and （Y2O3,MgO）-stabilized ZrO2 powders. Six precipitation processes for preparation of ZrO2-based ultrafine powders were designed separately, meanwhile different techniques used to control the agglomeration formation were proposed. By means of TEM, SEM, Raman spectroscopy and IR spectroscopy, the mechanisms of agglomeration control in the precipitation processes and post-precipitation and drying process were investigated. The experimental results show that adding appropriate anion surface active agents （such as PAA1460） or polymer （PEG1540 matching with PEG200） in aqueous solution systems during precipitation processes could reinforce charge effect and location effect for gel particles interface. Adding wetting agents to wet gels washing with distilled water during drying process could change interface structure of gel particles and decrease surface tension between gel particles. The agglomeration control in the precipitation, post-precipitation and drying processes had remarkable influence on the characteristics of powders. By adding various macromolecules in the processes, the agglomeration state could be controlled efficiently, and the characteristics of powders were improved.展开更多
Nano Y2O3:Eu3+ fluorescence powder was prepared by thermal decomposition of the rare earth citric acid complexes.The structure,size,morphology and luminescent properties of fluorescence powder were investigated by mea...Nano Y2O3:Eu3+ fluorescence powder was prepared by thermal decomposition of the rare earth citric acid complexes.The structure,size,morphology and luminescent properties of fluorescence powder were investigated by means of XRD and TEM.The results show that the crystal structure of nano Y2O3:Eu3+fluorescence powder is cubic,and the size of the particles is between 20 nm and 60 nm.The phosphors has the maximum excitation peak at 248 nm,and the maximum emission peak at 615 nm.展开更多
文摘Chemical coprecipitation was used to produce ultrafine and easily sinterable Y2O3-stabilized and （Y2O3,MgO）-stabilized ZrO2 powders. Six precipitation processes for preparation of ZrO2-based ultrafine powders were designed separately, meanwhile different techniques used to control the agglomeration formation were proposed. By means of TEM, SEM, Raman spectroscopy and IR spectroscopy, the mechanisms of agglomeration control in the precipitation processes and post-precipitation and drying process were investigated. The experimental results show that adding appropriate anion surface active agents （such as PAA1460） or polymer （PEG1540 matching with PEG200） in aqueous solution systems during precipitation processes could reinforce charge effect and location effect for gel particles interface. Adding wetting agents to wet gels washing with distilled water during drying process could change interface structure of gel particles and decrease surface tension between gel particles. The agglomeration control in the precipitation, post-precipitation and drying processes had remarkable influence on the characteristics of powders. By adding various macromolecules in the processes, the agglomeration state could be controlled efficiently, and the characteristics of powders were improved.
文摘Nano Y2O3:Eu3+ fluorescence powder was prepared by thermal decomposition of the rare earth citric acid complexes.The structure,size,morphology and luminescent properties of fluorescence powder were investigated by means of XRD and TEM.The results show that the crystal structure of nano Y2O3:Eu3+fluorescence powder is cubic,and the size of the particles is between 20 nm and 60 nm.The phosphors has the maximum excitation peak at 248 nm,and the maximum emission peak at 615 nm.
