3D porous nano-LiMn2O4(nano-LMO)is successfully prepared at 250℃ by a low temperature pyrolysis,using porous MnO2 and lithium acetate as reactants.The as-formed porous samples are demonstrated to be constructed by we...3D porous nano-LiMn2O4(nano-LMO)is successfully prepared at 250℃ by a low temperature pyrolysis,using porous MnO2 and lithium acetate as reactants.The as-formed porous samples are demonstrated to be constructed by well-defined and uniform cubic nanocrystals with particle sizes regulated from tens to hundreds of nanometers by adjusting the annealing temperature.Due to its proper particle size with perfect crystallization(-50 nm)and rich pores,sample LMO-265,prepared at 265℃,exhibits high performance as an aqueous lithium ion cathode.It can present a high specific capacity of 102 mAh g1 at a current density of 5℃ with a greatly improved rate capability(57.3%,68C)and capacity retention(70.7%,after 5000 cycles at 13.5C)in 1 M Li_(2)SO_(4).When assembled with commercial used active carbon(AC)to form an aqueous hybrid capacitor,it can deliver a high energy density of 15.8 Wh kg1 at a large power density of 9 kW kg1 with a good cycling life of 71.6%after 5000 at 2 Ag^(-1).Considering of its simple and economical preparation,as-prepared porous LMO can be regarded as a promising high-performance cathode material in aqueous electrolyte.展开更多
基金supported by National Natural Science Foundation of China for Youth(Grant No.21901153)the Shanghai Municipal Science and Technology Commission(Grant No.14DZ2261200,15DZ2260300)111 project(D16002)and Shanghai Municipal Education Commission under Project of Shanghai Teachers Incentive plan.
文摘3D porous nano-LiMn2O4(nano-LMO)is successfully prepared at 250℃ by a low temperature pyrolysis,using porous MnO2 and lithium acetate as reactants.The as-formed porous samples are demonstrated to be constructed by well-defined and uniform cubic nanocrystals with particle sizes regulated from tens to hundreds of nanometers by adjusting the annealing temperature.Due to its proper particle size with perfect crystallization(-50 nm)and rich pores,sample LMO-265,prepared at 265℃,exhibits high performance as an aqueous lithium ion cathode.It can present a high specific capacity of 102 mAh g1 at a current density of 5℃ with a greatly improved rate capability(57.3%,68C)and capacity retention(70.7%,after 5000 cycles at 13.5C)in 1 M Li_(2)SO_(4).When assembled with commercial used active carbon(AC)to form an aqueous hybrid capacitor,it can deliver a high energy density of 15.8 Wh kg1 at a large power density of 9 kW kg1 with a good cycling life of 71.6%after 5000 at 2 Ag^(-1).Considering of its simple and economical preparation,as-prepared porous LMO can be regarded as a promising high-performance cathode material in aqueous electrolyte.
