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
Li_2Ni Ti O_4是一种岩盐结构的层状锂电正极材料,该材料能够嵌脱2个Li离子,首次充电比容量大,但不可逆容量也很大。本研究通过掺杂Mo元素,优化电化学性能,提高了可逆比容量。通过柠檬酸溶胶凝胶法,以Li NO_3、Ni(NO_3)_2·6H_2O和...Li_2Ni Ti O_4是一种岩盐结构的层状锂电正极材料,该材料能够嵌脱2个Li离子,首次充电比容量大,但不可逆容量也很大。本研究通过掺杂Mo元素,优化电化学性能,提高了可逆比容量。通过柠檬酸溶胶凝胶法,以Li NO_3、Ni(NO_3)_2·6H_2O和钛酸四丁酯为原料,以四水钼酸铵为钼源,合成了Li_2Ni Ti O_4和Li_(2.4)Ni_(0.67)Ti_(0.67)Mo_(0.26)O_4,可逆比容量从85 m Ah/g提高到162 m Ah/g,通过和炭黑复合,优化导电性,可逆比容量进一步提升到210 m Ah/g。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Li_2Ni Ti O_4是一种岩盐结构的层状锂电正极材料,该材料能够嵌脱2个Li离子,首次充电比容量大,但不可逆容量也很大。本研究通过掺杂Mo元素,优化电化学性能,提高了可逆比容量。通过柠檬酸溶胶凝胶法,以Li NO_3、Ni(NO_3)_2·6H_2O和钛酸四丁酯为原料,以四水钼酸铵为钼源,合成了Li_2Ni Ti O_4和Li_(2.4)Ni_(0.67)Ti_(0.67)Mo_(0.26)O_4,可逆比容量从85 m Ah/g提高到162 m Ah/g,通过和炭黑复合,优化导电性,可逆比容量进一步提升到210 m Ah/g。
