ZrO2 nanoparticles were prepared under high temperature and high pressure conditions by precipitation from metal nitrates with aqueous potassium hydroxide. The effects of synthesis parameters, such as the concentratio...ZrO2 nanoparticles were prepared under high temperature and high pressure conditions by precipitation from metal nitrates with aqueous potassium hydroxide. The effects of synthesis parameters, such as the concentration of starting solution, pH of starting solution, reaction temperature and time, were discussed. The results show that the ZrO2 nanoparticles are obtained at 230-270 ℃. The average size and size distribution of the synthesized particles are below 10 nm and narrow, respectively. The XRD pattern shows that the synthesized particles are composed of crystalline. The synthesis of ZrO2 nanosized crystalline particles is possible under glycothermal conditions in ethylene glycol solution.展开更多
Metallic Pd clusters were embedded into TiO2 nanoparticles that were synthesized within reverse micelle via a solution reduction of Pd(NO3)2 by hydrazine hydrate. The size of the particles can be controlled by manipul...Metallic Pd clusters were embedded into TiO2 nanoparticles that were synthesized within reverse micelle via a solution reduction of Pd(NO3)2 by hydrazine hydrate. The size of the particles can be controlled by manipulating the relative rates of the hydrolysis and condensation reactions of titanium tetra-isopropoxide within the micro-emulsion. The spherical equivalent size for the Pd clusters formed in TiO2 matrix was estimated to be around (3±1) nm. The presence of Pd in the matrix was demonstrated by EDS spectroscopy. The effects of synthesis parameters, such as the concentration of Pd solution, the molar ratio of water to TIP, and the molar ratio of water to surfactant, were discussed.展开更多
The nanosized Ba(CoxNb1-x)O3(BCN) particles were prepared under high temperature and pressure conditions by precipitation from metal nitrates with aqueous potassium hydroxide. Ba(CoxNb1-x)O3 powders were obtained in t...The nanosized Ba(CoxNb1-x)O3(BCN) particles were prepared under high temperature and pressure conditions by precipitation from metal nitrates with aqueous potassium hydroxide. Ba(CoxNb1-x)O3 powders were obtained in the temperature range of 170-210 ℃ for 6 h. The results show that the average size of the synthesized particles increases with increasing reaction temperature. The average size of the synthesized particles is about 10 nm. The crystalline phase of the synthesized particles is found to be Ba(CoxNb1-x)O3. Ceramics derived from the nano BCN powders could achieve high sintering density at a relatively low sintering temperature.展开更多
基金supported by the Ministry of Education,Science Technology (MEST) and Korea Industrial Technology Foundation (KOTEF) through the Human Resource Training Project for Regional Innovation
文摘ZrO2 nanoparticles were prepared under high temperature and high pressure conditions by precipitation from metal nitrates with aqueous potassium hydroxide. The effects of synthesis parameters, such as the concentration of starting solution, pH of starting solution, reaction temperature and time, were discussed. The results show that the ZrO2 nanoparticles are obtained at 230-270 ℃. The average size and size distribution of the synthesized particles are below 10 nm and narrow, respectively. The XRD pattern shows that the synthesized particles are composed of crystalline. The synthesis of ZrO2 nanosized crystalline particles is possible under glycothermal conditions in ethylene glycol solution.
基金supported by the Ministry of Education,Science Technology(MEST) and Korea Industrial Technology Foundation(KOTEF) through the Human Resource Training Project for Regional Innovation
文摘Metallic Pd clusters were embedded into TiO2 nanoparticles that were synthesized within reverse micelle via a solution reduction of Pd(NO3)2 by hydrazine hydrate. The size of the particles can be controlled by manipulating the relative rates of the hydrolysis and condensation reactions of titanium tetra-isopropoxide within the micro-emulsion. The spherical equivalent size for the Pd clusters formed in TiO2 matrix was estimated to be around (3±1) nm. The presence of Pd in the matrix was demonstrated by EDS spectroscopy. The effects of synthesis parameters, such as the concentration of Pd solution, the molar ratio of water to TIP, and the molar ratio of water to surfactant, were discussed.
基金supported by the Ministry of Education,Science Technology (MEST) and Korea Industrial Technology Foundation (KOTEF) through the Human Resource Training Project for Regional Innovation
文摘The nanosized Ba(CoxNb1-x)O3(BCN) particles were prepared under high temperature and pressure conditions by precipitation from metal nitrates with aqueous potassium hydroxide. Ba(CoxNb1-x)O3 powders were obtained in the temperature range of 170-210 ℃ for 6 h. The results show that the average size of the synthesized particles increases with increasing reaction temperature. The average size of the synthesized particles is about 10 nm. The crystalline phase of the synthesized particles is found to be Ba(CoxNb1-x)O3. Ceramics derived from the nano BCN powders could achieve high sintering density at a relatively low sintering temperature.