In this work, pure α-Fe2O3 and Er2O3-Fe2O3 nanotubes were synthesized by a simple single-capillary electrospin- ning technology followed by calcination treatment. The morphologies and crystal structures of the as-pre...In this work, pure α-Fe2O3 and Er2O3-Fe2O3 nanotubes were synthesized by a simple single-capillary electrospin- ning technology followed by calcination treatment. The morphologies and crystal structures of the as-prepared samples were characterized by scanning electron microscopy and x-ray diffraction, respectively. The gas-sensing properties of the as-prepared samples have been researched, and the result shows that the Er2O3-Fe2O3 nanotubes exhibit much better sen- sitivity to ethanol. The response value of Er2O3-Fe2O3 nanotubes to 10 ppm ethanol is 21 at the operating temperature 240α, which is 14 times larger than that of pure α-Fe2O3 nanotubes （response value is 1.5）. The ethanol sensing properties of α-Fe2O3 nanotubes are remarkably enhanced by doping Er, and the lowest detection limit of Er2O3-Fe2O3 nanotubes is 300 ppb, to which the response value is about 2. The response and recovery times are about 4 s and 70 s to 10 ppm ethanol, respectively. In addition, the Er2O3-Fe2O3 nanotubes possess good selectivity and long-term stability.展开更多
The microstructure, electrical and dielectric properties, and DC-accelerated aging of the ZPCCA （ZnO-Pr6O11-CoO- Cr203-A1203） ceramics were investigated with various contents of Er203. The ceramic phases consisted o...The microstructure, electrical and dielectric properties, and DC-accelerated aging of the ZPCCA （ZnO-Pr6O11-CoO- Cr203-A1203） ceramics were investigated with various contents of Er203. The ceramic phases consisted of a bulk phase of ZnO grains, and a minor secondary phase of mixture of Pr6O11 and Er203. The increase of the content of doped Er203 increased the densities of sintered pellet from 5.66 to 5.85 g/cm3, and decreased the average grain size from 9.6 to 6.3 μm. With the increase of the content of doped Er203, the breakdown field increased from 2390 to 4530 V/cm, and the nonlinear coefficient increased from 28.4 to 39.1. The sample doped with 0.25 mol.% Er203 exhibited the strongest electrical stability; variation rates for the breakdown field measured at 1.0 mA/cm2, and for the non-ohmic coefficient were -3.4% and -23,8%, respectively, after application of a stress of 0.95 Eu/125 ℃/24 h.展开更多
An Er203 coating-type selective emitter for themophotovoltaic application was prepared by plasma spray technology. The test results show that plasma spray technology could be used to prepare the Er203 coating-type sel...An Er203 coating-type selective emitter for themophotovoltaic application was prepared by plasma spray technology. The test results show that plasma spray technology could be used to prepare the Er203 coating-type selective emitter with good stability at 1400℃. Based on the measurements of the high temperature normal spectral emissivity and the spectral hemispherical emissivity of the samples at room temperature, the influence of the coating thickness was discussed, and the selective emission performance of the sample was evaluated using radiative efficiency as the criterion. The results demonstrate that the emission of substrate could not be neglected unless the coating thickness would be larger than the penetration depth, which is around 100 μm. The selective emission peak of the Er203 coating occurs at 1550 nm, matching well with the GaSb cells. However, the radiative efficiency is not larger than that of the SiC emitter, because the non-convertible emission of 1.725-5 μm accounts for a large proportion of the total radiation power, especially at high temperature. Effective suppression of this band emission is essential to the improvement of the radiation efficiency of the emitter.展开更多
基金supported by Jilin Provincial Science and Technology Department,China(Grant No.20140204027GX)the Challenge Cup for College Students,China(Grant No.450060497053)
文摘In this work, pure α-Fe2O3 and Er2O3-Fe2O3 nanotubes were synthesized by a simple single-capillary electrospin- ning technology followed by calcination treatment. The morphologies and crystal structures of the as-prepared samples were characterized by scanning electron microscopy and x-ray diffraction, respectively. The gas-sensing properties of the as-prepared samples have been researched, and the result shows that the Er2O3-Fe2O3 nanotubes exhibit much better sen- sitivity to ethanol. The response value of Er2O3-Fe2O3 nanotubes to 10 ppm ethanol is 21 at the operating temperature 240α, which is 14 times larger than that of pure α-Fe2O3 nanotubes （response value is 1.5）. The ethanol sensing properties of α-Fe2O3 nanotubes are remarkably enhanced by doping Er, and the lowest detection limit of Er2O3-Fe2O3 nanotubes is 300 ppb, to which the response value is about 2. The response and recovery times are about 4 s and 70 s to 10 ppm ethanol, respectively. In addition, the Er2O3-Fe2O3 nanotubes possess good selectivity and long-term stability.
文摘The microstructure, electrical and dielectric properties, and DC-accelerated aging of the ZPCCA （ZnO-Pr6O11-CoO- Cr203-A1203） ceramics were investigated with various contents of Er203. The ceramic phases consisted of a bulk phase of ZnO grains, and a minor secondary phase of mixture of Pr6O11 and Er203. The increase of the content of doped Er203 increased the densities of sintered pellet from 5.66 to 5.85 g/cm3, and decreased the average grain size from 9.6 to 6.3 μm. With the increase of the content of doped Er203, the breakdown field increased from 2390 to 4530 V/cm, and the nonlinear coefficient increased from 28.4 to 39.1. The sample doped with 0.25 mol.% Er203 exhibited the strongest electrical stability; variation rates for the breakdown field measured at 1.0 mA/cm2, and for the non-ohmic coefficient were -3.4% and -23,8%, respectively, after application of a stress of 0.95 Eu/125 ℃/24 h.
基金supported by the Key Laboratory of Inorganic Coating Materials,Chinese Academy of Sciencesthe Fundamental Research Funds for the Central Universities
文摘An Er203 coating-type selective emitter for themophotovoltaic application was prepared by plasma spray technology. The test results show that plasma spray technology could be used to prepare the Er203 coating-type selective emitter with good stability at 1400℃. Based on the measurements of the high temperature normal spectral emissivity and the spectral hemispherical emissivity of the samples at room temperature, the influence of the coating thickness was discussed, and the selective emission performance of the sample was evaluated using radiative efficiency as the criterion. The results demonstrate that the emission of substrate could not be neglected unless the coating thickness would be larger than the penetration depth, which is around 100 μm. The selective emission peak of the Er203 coating occurs at 1550 nm, matching well with the GaSb cells. However, the radiative efficiency is not larger than that of the SiC emitter, because the non-convertible emission of 1.725-5 μm accounts for a large proportion of the total radiation power, especially at high temperature. Effective suppression of this band emission is essential to the improvement of the radiation efficiency of the emitter.
