An ordered hexagonal pore sub-mesostructured silica was synthesized via ionic liquid 1-hexadecane-3-methylimidazolium bromide(C16MIB) as structure-directing agents in acidic media.By combining the results of transmisi...An ordered hexagonal pore sub-mesostructured silica was synthesized via ionic liquid 1-hexadecane-3-methylimidazolium bromide(C16MIB) as structure-directing agents in acidic media.By combining the results of transmision electron microscopy,X-ray diffraction and surface area measurements,an elementary structure and characterization of the samples was obtained.This material performs two-dimensional hexagonal framework structure being analogous to MCM-41 and SBA-3 silicas in long range order,but the position of reflection peaks of X-ray diffraction shifts to a wide angle compared with those of MCM-41 and SBA-3.The sub-mesostructured silica has high BET specific surface area of 1360 m2/g,as well as small pore size of 1.8 nm.展开更多
采用一步水热法合成了棒状NiCo_2O_4前驱体,并通过调节水热反应过程中碳源(葡萄糖)的加入量以及后续热处理条件(气氛、温度)得到了一系列不同的NiCo_2O_4及NiCo_2O_4@C产物,并对这些产物的结构、形貌及电化学储锂性能进行了测试.结果表...采用一步水热法合成了棒状NiCo_2O_4前驱体,并通过调节水热反应过程中碳源(葡萄糖)的加入量以及后续热处理条件(气氛、温度)得到了一系列不同的NiCo_2O_4及NiCo_2O_4@C产物,并对这些产物的结构、形貌及电化学储锂性能进行了测试.结果表明,适当的葡萄糖加入量(0.5 g)配合合理的煅烧条件(400℃,氮气气氛)可以获得倍率性能和循环稳定性兼具的NiCo_2O_4@C纳米复合材料.在100 m A/g的电流密度下,该材料的首次充/放电比容量为634.1/767.2 m A·h/g,对应的库仑效率为82.7%,5周后的放电比容量为650.1 m A·h/g,容量保持率为84.74%,且在300 m A/g的高电流密度下可逆比容量仍可保持在225.9m A·h/g.展开更多
文摘An ordered hexagonal pore sub-mesostructured silica was synthesized via ionic liquid 1-hexadecane-3-methylimidazolium bromide(C16MIB) as structure-directing agents in acidic media.By combining the results of transmision electron microscopy,X-ray diffraction and surface area measurements,an elementary structure and characterization of the samples was obtained.This material performs two-dimensional hexagonal framework structure being analogous to MCM-41 and SBA-3 silicas in long range order,but the position of reflection peaks of X-ray diffraction shifts to a wide angle compared with those of MCM-41 and SBA-3.The sub-mesostructured silica has high BET specific surface area of 1360 m2/g,as well as small pore size of 1.8 nm.
文摘采用一步水热法合成了棒状NiCo_2O_4前驱体,并通过调节水热反应过程中碳源(葡萄糖)的加入量以及后续热处理条件(气氛、温度)得到了一系列不同的NiCo_2O_4及NiCo_2O_4@C产物,并对这些产物的结构、形貌及电化学储锂性能进行了测试.结果表明,适当的葡萄糖加入量(0.5 g)配合合理的煅烧条件(400℃,氮气气氛)可以获得倍率性能和循环稳定性兼具的NiCo_2O_4@C纳米复合材料.在100 m A/g的电流密度下,该材料的首次充/放电比容量为634.1/767.2 m A·h/g,对应的库仑效率为82.7%,5周后的放电比容量为650.1 m A·h/g,容量保持率为84.74%,且在300 m A/g的高电流密度下可逆比容量仍可保持在225.9m A·h/g.