Uniform nanosized NiO particles were prepared by a chedrical coprecipitation usingNiCl2.6H2O as the starting material. The relationship between various annealing telnperaturesand grain size of NiO crystallite was inve...Uniform nanosized NiO particles were prepared by a chedrical coprecipitation usingNiCl2.6H2O as the starting material. The relationship between various annealing telnperaturesand grain size of NiO crystallite was investigated. Optical reflectivity spectra of Nanometer-sizedNiO powders at roonl temperature were studied. The results show that seven optical absorptionbands (P1. P2. P3. P4. P5. P6 and P7) with the peak energies of 3.30, 2.99, 2.78, 2.25,1.92, 1.72 and 1.07eV, respectively, are located on a continuous refiectivity background. P1.P2. P3 and P4 exhibit "blue shift", but P5. P6 and P7 present "red shift"in comparison withthat of single crystal NiO. The continuous reflectivity background increases rapidly with increasingthe annealing temperature from 500℃ to 600℃ to 700℃. The origins of P1 to P7 and thereasons of "blue shift", "red shift" and the increase of the reflectivity background with increasingthe annealing temperature have been analyzed in detail.展开更多
Nanocrystal SmBO3 powders were synthesized by nitrate-citrate sol-gel combustion method. The phase evolution, morphologies and absorbency of the synthesized powders were characterized by X-ray diffraction （XRD）, Fie...Nanocrystal SmBO3 powders were synthesized by nitrate-citrate sol-gel combustion method. The phase evolution, morphologies and absorbency of the synthesized powders were characterized by X-ray diffraction （XRD）, Field emission scanning electronic microscope （FESEM）, Fourier transform infrared spectroscopy （FFIR） and UV-3101PC spectrophotometer （UVPC）, respectively. XRD and FESEM results showed that pure SmBO3 phase was obtained at 750 ℃, with an average original particle size of about 100 nm. FTIR showed that there were apparently concentrated absorbent peaks between 500 and 1400 cm^-1. Moreover, the reflectivity of the powders apparently decreased at the wavelength between 1.05 and 1.15 μm. Therefore, SmBO3 might be a kind of absorbent material for infrared laser.展开更多
文摘Uniform nanosized NiO particles were prepared by a chedrical coprecipitation usingNiCl2.6H2O as the starting material. The relationship between various annealing telnperaturesand grain size of NiO crystallite was investigated. Optical reflectivity spectra of Nanometer-sizedNiO powders at roonl temperature were studied. The results show that seven optical absorptionbands (P1. P2. P3. P4. P5. P6 and P7) with the peak energies of 3.30, 2.99, 2.78, 2.25,1.92, 1.72 and 1.07eV, respectively, are located on a continuous refiectivity background. P1.P2. P3 and P4 exhibit "blue shift", but P5. P6 and P7 present "red shift"in comparison withthat of single crystal NiO. The continuous reflectivity background increases rapidly with increasingthe annealing temperature from 500℃ to 600℃ to 700℃. The origins of P1 to P7 and thereasons of "blue shift", "red shift" and the increase of the reflectivity background with increasingthe annealing temperature have been analyzed in detail.
基金supported by the 973 Research Project of China (6134502)
文摘Nanocrystal SmBO3 powders were synthesized by nitrate-citrate sol-gel combustion method. The phase evolution, morphologies and absorbency of the synthesized powders were characterized by X-ray diffraction （XRD）, Field emission scanning electronic microscope （FESEM）, Fourier transform infrared spectroscopy （FFIR） and UV-3101PC spectrophotometer （UVPC）, respectively. XRD and FESEM results showed that pure SmBO3 phase was obtained at 750 ℃, with an average original particle size of about 100 nm. FTIR showed that there were apparently concentrated absorbent peaks between 500 and 1400 cm^-1. Moreover, the reflectivity of the powders apparently decreased at the wavelength between 1.05 and 1.15 μm. Therefore, SmBO3 might be a kind of absorbent material for infrared laser.
