Thin-film lithium-ion battery of LiMn2O4/Li1.3Al0.3Ti1.7(PO4)3/LiMn2O4 was fabricated using Li1.3Al0.3Ti1.7(PO4)3 sintered pellet as both substrate and electrolyte. Li1.3Al0.3Ti1.7(PO4)3 sintered pellet was prepared b...Thin-film lithium-ion battery of LiMn2O4/Li1.3Al0.3Ti1.7(PO4)3/LiMn2O4 was fabricated using Li1.3Al0.3Ti1.7(PO4)3 sintered pellet as both substrate and electrolyte. Li1.3Al0.3Ti1.7(PO4)3 sintered pellet was prepared by sol-gel technique, and the thin-film battery was heat-treated by rapid thermal annealing. Phase identification, morphology and electrochemical properties of the components and thin-film battery were investigated by X-ray diffractometry, scanning electron microscopy, electrochemical impedance spectroscopy and galvanostatic charge-discharge experiments. The results show that Li1.3Al0.3Ti1.7(PO4)3 possesses a electrochemical window of 2.4 V and an ionic conductivity of 1.2 ×10-4 S/cm. With Li1.3Al0.3Ti1.7(PO4)3 sintered pellet as both substrate and solid electrolyte, the fabricated thin-film battery with an open circuit voltage of 1.2V can be easily cycled.展开更多
ZnO-based thick film varistors have been fabricated by Y203 doping and low-temperature sintering, of which the sample with the best electrical properties has a high potential gradient value of 3159.4 V/mm. The effects...ZnO-based thick film varistors have been fabricated by Y203 doping and low-temperature sintering, of which the sample with the best electrical properties has a high potential gradient value of 3159.4 V/mm. The effects of Y2O3 doping concentration and sintering temperature on the potential gradient of the samples were systematically investigated. The results show that the sample with the best electrical properties can be obtained by doping 0.08 mol% Y2O3 and sintering at 725℃. Under these optimum preparation conditions, the leakage current and the nonlinear coefficient are found to be 36.4 gA and 13.1. The sample with the best electrical properties has a grain size of 1.290um, a single grain boundary voltage of 4.08 V, a barrier height of 0.81 eV, and a depletion layer width of 10.2 nm, which are determined by thermionic emission. Small grain size with good grain boundary characteristics is beneficial to improve the electrical properties of varistors and promote the potential gradient.展开更多
The present work mainly describes the technology for preparing indium-tin oxide （ITO） targets by cold isostatic pressing （CIP） and normal pressure sintering process. ITO powders were produced by chemical co-precip...The present work mainly describes the technology for preparing indium-tin oxide （ITO） targets by cold isostatic pressing （CIP） and normal pressure sintering process. ITO powders were produced by chemical co-precipitation and shaped into an ITO green compact with a relative density of 60% by CIP under 300 MPa. Then, an ITO target with a relative density larger than 99.6% was obtained by sintering this green compact at 1550℃ for 8 h. The effects of forming pressure, sintering temperature and sintering time on the density of the target were inves- tigated. Also, a discussion was made on the sintering atmosphere.展开更多
Dynamic friction polishing （DFP） is one of the most promising methods appropriate for polishing CVD diamond film with high efficiency and low cost. By this method CVD diamond film is polished through being simply pr...Dynamic friction polishing （DFP） is one of the most promising methods appropriate for polishing CVD diamond film with high efficiency and low cost. By this method CVD diamond film is polished through being simply pressed against a metal disc rotating at a high speed utilizing the thermochemical reaction occurring as a result of dynamic friction between them in the atmosphere. However, the relatively soft materials such as stainless steel, cast iron and nickel alloy widely used for polishing CVD diamond film are easy to wear and adhere to diamond film surface, which may further lead to low efficiency and poor polishing quality. In this paper, FeNiCr matrix-TiC composite used as grinding wheel for polishing CVD diamond film was obtained by combination of mechanical alloying （MA） and spark plasma sintering （SPS）. The process of ball milling, composition, density, hardness, high-temperature oxidation resistance and wear resistance of the sintered piece were analyzed. The results show that TiC was introduced in MA-SPS process and had good combination with FeNiCr matrix and even distribution in the matrix. The density of composite can be improved by mechanical alloying. The FeNiCr matrix-TiC composite obtained at 1273 K was found to be superior to at 1173 K sinterin8 in hardness, high-temperature oxidation resistance and wearability. These properties are more favorable than SUS304 for the preparation of high-performance grinding wheel for polishing CVD diamond film.展开更多
基金Projects(03JJY6005 04JJ4038) supported by the Natural Science Foundation of Hunan Province, China Project(05C140) supported by the Education Office of Hunan Province, China
文摘Thin-film lithium-ion battery of LiMn2O4/Li1.3Al0.3Ti1.7(PO4)3/LiMn2O4 was fabricated using Li1.3Al0.3Ti1.7(PO4)3 sintered pellet as both substrate and electrolyte. Li1.3Al0.3Ti1.7(PO4)3 sintered pellet was prepared by sol-gel technique, and the thin-film battery was heat-treated by rapid thermal annealing. Phase identification, morphology and electrochemical properties of the components and thin-film battery were investigated by X-ray diffractometry, scanning electron microscopy, electrochemical impedance spectroscopy and galvanostatic charge-discharge experiments. The results show that Li1.3Al0.3Ti1.7(PO4)3 possesses a electrochemical window of 2.4 V and an ionic conductivity of 1.2 ×10-4 S/cm. With Li1.3Al0.3Ti1.7(PO4)3 sintered pellet as both substrate and solid electrolyte, the fabricated thin-film battery with an open circuit voltage of 1.2V can be easily cycled.
基金supported by the Nano Special Plan from Shanghai Municipal Science and Technology Plan of Commission (No 0852nm06000)the Shanghai Municipal Natural Science Foundation (No 08ZR1406700)
文摘ZnO-based thick film varistors have been fabricated by Y203 doping and low-temperature sintering, of which the sample with the best electrical properties has a high potential gradient value of 3159.4 V/mm. The effects of Y2O3 doping concentration and sintering temperature on the potential gradient of the samples were systematically investigated. The results show that the sample with the best electrical properties can be obtained by doping 0.08 mol% Y2O3 and sintering at 725℃. Under these optimum preparation conditions, the leakage current and the nonlinear coefficient are found to be 36.4 gA and 13.1. The sample with the best electrical properties has a grain size of 1.290um, a single grain boundary voltage of 4.08 V, a barrier height of 0.81 eV, and a depletion layer width of 10.2 nm, which are determined by thermionic emission. Small grain size with good grain boundary characteristics is beneficial to improve the electrical properties of varistors and promote the potential gradient.
基金supported by the National High-Tech Research and Development Program of China(No. 2004AA303542)
文摘The present work mainly describes the technology for preparing indium-tin oxide （ITO） targets by cold isostatic pressing （CIP） and normal pressure sintering process. ITO powders were produced by chemical co-precipitation and shaped into an ITO green compact with a relative density of 60% by CIP under 300 MPa. Then, an ITO target with a relative density larger than 99.6% was obtained by sintering this green compact at 1550℃ for 8 h. The effects of forming pressure, sintering temperature and sintering time on the density of the target were inves- tigated. Also, a discussion was made on the sintering atmosphere.
基金supported by the National Natural Science Foundation of China under grant No. 50575034.
文摘Dynamic friction polishing （DFP） is one of the most promising methods appropriate for polishing CVD diamond film with high efficiency and low cost. By this method CVD diamond film is polished through being simply pressed against a metal disc rotating at a high speed utilizing the thermochemical reaction occurring as a result of dynamic friction between them in the atmosphere. However, the relatively soft materials such as stainless steel, cast iron and nickel alloy widely used for polishing CVD diamond film are easy to wear and adhere to diamond film surface, which may further lead to low efficiency and poor polishing quality. In this paper, FeNiCr matrix-TiC composite used as grinding wheel for polishing CVD diamond film was obtained by combination of mechanical alloying （MA） and spark plasma sintering （SPS）. The process of ball milling, composition, density, hardness, high-temperature oxidation resistance and wear resistance of the sintered piece were analyzed. The results show that TiC was introduced in MA-SPS process and had good combination with FeNiCr matrix and even distribution in the matrix. The density of composite can be improved by mechanical alloying. The FeNiCr matrix-TiC composite obtained at 1273 K was found to be superior to at 1173 K sinterin8 in hardness, high-temperature oxidation resistance and wearability. These properties are more favorable than SUS304 for the preparation of high-performance grinding wheel for polishing CVD diamond film.
