The dehydrating activation energies of the hematite with several doped ions used for the alcohol sensor were determinated by thermogravimetric differential thermal analyzer (TG DTA) and the grain size of the samples w...The dehydrating activation energies of the hematite with several doped ions used for the alcohol sensor were determinated by thermogravimetric differential thermal analyzer (TG DTA) and the grain size of the samples were observed with TEM. The hematites with different doping amounts of Sn 4+ were investigated by Mssbauer spectrometer. It shows that the different doped ion is of influence for grain growth of the hematite. The decrease of grain size stemmed from the doped ion causes gas sensitivity for alcohol to increase and the dehydrating activation energy to decrease correspondingly. When the different amounts of Sn 4+ is doped in hematite, the microstructure of the hematite can be influenced.展开更多
In the water-in-oil mieroemulsion system of Triton X-100, 1-hexanol, cyclohexane and Fe（NO3）3 aqueous solution, α－Fe2O3 ultrafine particles were prepared by the method of precipitation using NH3. From transndssion...In the water-in-oil mieroemulsion system of Triton X-100, 1-hexanol, cyclohexane and Fe（NO3）3 aqueous solution, α－Fe2O3 ultrafine particles were prepared by the method of precipitation using NH3. From transndssion electron ndcrographs the mean dianreter of particles is about 3nm. The trifornlity of particle is good. These result have been confirmed by the method of Mossbauer spectrum measurement. The conditions of preparation of α－Fe2O3 ultrallne particles could be controlled easily and the reaction medium could be used cyclically.展开更多
文摘The dehydrating activation energies of the hematite with several doped ions used for the alcohol sensor were determinated by thermogravimetric differential thermal analyzer (TG DTA) and the grain size of the samples were observed with TEM. The hematites with different doping amounts of Sn 4+ were investigated by Mssbauer spectrometer. It shows that the different doped ion is of influence for grain growth of the hematite. The decrease of grain size stemmed from the doped ion causes gas sensitivity for alcohol to increase and the dehydrating activation energy to decrease correspondingly. When the different amounts of Sn 4+ is doped in hematite, the microstructure of the hematite can be influenced.
文摘In the water-in-oil mieroemulsion system of Triton X-100, 1-hexanol, cyclohexane and Fe（NO3）3 aqueous solution, α－Fe2O3 ultrafine particles were prepared by the method of precipitation using NH3. From transndssion electron ndcrographs the mean dianreter of particles is about 3nm. The trifornlity of particle is good. These result have been confirmed by the method of Mossbauer spectrum measurement. The conditions of preparation of α－Fe2O3 ultrallne particles could be controlled easily and the reaction medium could be used cyclically.
