s: Ultrafine A2La2Ti3O10 (A=K, Na) powders with laminar structure were successfully synthesized by citric acid sol-gel method using ANO3(A=K, Na)?La(NO3)3?Ti(OBu)4 and citric acid as starting precursors. The crystalli...s: Ultrafine A2La2Ti3O10 (A=K, Na) powders with laminar structure were successfully synthesized by citric acid sol-gel method using ANO3(A=K, Na)?La(NO3)3?Ti(OBu)4 and citric acid as starting precursors. The crystalline phase of A2La2Ti3O10 can be obtained by thermal decomposition of citrate complex precursors at a relatively low temperature of 800 ℃ (600 ℃ for A=Na), about 300 ℃(500 ℃ for A=Na) lower than that of conventional solid state reaction process. The properties of the citrate precursors and the calcined powders were characterized by Infrared spectroscopy (IR), X-ray diffraction (XRD), transmission electron microscopy (TEM), thermal-gravimetric-differential thermal analysis (TG-DTA), inductively coupled plasma (ICP) and Brunauer-Emmett-Teller (BET) techniques. Results show that the average size of A2La2Ti3O10 powders obtained by citric acid sol-gel route was reduced to 200 nm×250 nm and the specific surface area was up to 19 m2·g-1. At the same time, the product was with more regular morphological characteristics. The synthesis process and the formation of A2La2Ti3O10 were also discussed. The obtained A2La2Ti3O10 was found to be transformed from A2La2Ti3O9.5 during the formation process.展开更多
用柠檬酸溶胶-凝胶燃烧法制备了锂离子电池正极材料L iN i0.5Co0.5O2,并对材料进行了热分析、红外分析及X射线衍射分析。研究结果表明,L iN i0.5Co0.5O2干凝胶在空气中自蔓延燃烧,燃烧产物再于800℃烧结10 h,可避免因缺氧而导致杂相L i2...用柠檬酸溶胶-凝胶燃烧法制备了锂离子电池正极材料L iN i0.5Co0.5O2,并对材料进行了热分析、红外分析及X射线衍射分析。研究结果表明,L iN i0.5Co0.5O2干凝胶在空气中自蔓延燃烧,燃烧产物再于800℃烧结10 h,可避免因缺氧而导致杂相L i2CO3、L i2N i8O10的产生,产物晶型完整。展开更多
文摘s: Ultrafine A2La2Ti3O10 (A=K, Na) powders with laminar structure were successfully synthesized by citric acid sol-gel method using ANO3(A=K, Na)?La(NO3)3?Ti(OBu)4 and citric acid as starting precursors. The crystalline phase of A2La2Ti3O10 can be obtained by thermal decomposition of citrate complex precursors at a relatively low temperature of 800 ℃ (600 ℃ for A=Na), about 300 ℃(500 ℃ for A=Na) lower than that of conventional solid state reaction process. The properties of the citrate precursors and the calcined powders were characterized by Infrared spectroscopy (IR), X-ray diffraction (XRD), transmission electron microscopy (TEM), thermal-gravimetric-differential thermal analysis (TG-DTA), inductively coupled plasma (ICP) and Brunauer-Emmett-Teller (BET) techniques. Results show that the average size of A2La2Ti3O10 powders obtained by citric acid sol-gel route was reduced to 200 nm×250 nm and the specific surface area was up to 19 m2·g-1. At the same time, the product was with more regular morphological characteristics. The synthesis process and the formation of A2La2Ti3O10 were also discussed. The obtained A2La2Ti3O10 was found to be transformed from A2La2Ti3O9.5 during the formation process.
文摘用柠檬酸溶胶-凝胶燃烧法制备了锂离子电池正极材料L iN i0.5Co0.5O2,并对材料进行了热分析、红外分析及X射线衍射分析。研究结果表明,L iN i0.5Co0.5O2干凝胶在空气中自蔓延燃烧,燃烧产物再于800℃烧结10 h,可避免因缺氧而导致杂相L i2CO3、L i2N i8O10的产生,产物晶型完整。
