In this article,MnFe2O4 nanocrystals were synthesized by coprecipitation at low temperature,and the effects of temperature,time and additive on crystallization and particle sizes of samples were also studied.In additi...In this article,MnFe2O4 nanocrystals were synthesized by coprecipitation at low temperature,and the effects of temperature,time and additive on crystallization and particle sizes of samples were also studied.In addition,the samples prepared by the method were characterized by XRD,TEM and VSM,respectively.展开更多
Nano-spinel Li x Mn 2 O 4 (0.6≤x≤1.0)was synthesized by two steps of copre cipitation and calcination.The influences of calcination temperature,time and Li /Mn ratio on the crystal structure and the particle size of...Nano-spinel Li x Mn 2 O 4 (0.6≤x≤1.0)was synthesized by two steps of copre cipitation and calcination.The influences of calcination temperature,time and Li /Mn ratio on the crystal structure and the particle size of Li x Mn 2 O 4 were investigated.It was shown that the higher the calcination temperature,the more complete the crystal structure,and the larger the partic le size.Moreover,the influence of c alcination time on the crystal structure was insignificant when it was more than 3h at 700℃.With the increase of x in Li x Mn 2 O 4 in the range of 0.6~1.0,the d 111 and lattice parameter a increased fi rst and then decreased.The electrochemical properties of nano-spinel LiMn 2 O 4 using as cathode material of lithium-ion battery were studied.The low di scharge capacity might be due to the irreversible capacity loss brou ght by the large surface area and latt ice vacancies of the nano-spinel.展开更多
文摘In this article,MnFe2O4 nanocrystals were synthesized by coprecipitation at low temperature,and the effects of temperature,time and additive on crystallization and particle sizes of samples were also studied.In addition,the samples prepared by the method were characterized by XRD,TEM and VSM,respectively.
文摘Nano-spinel Li x Mn 2 O 4 (0.6≤x≤1.0)was synthesized by two steps of copre cipitation and calcination.The influences of calcination temperature,time and Li /Mn ratio on the crystal structure and the particle size of Li x Mn 2 O 4 were investigated.It was shown that the higher the calcination temperature,the more complete the crystal structure,and the larger the partic le size.Moreover,the influence of c alcination time on the crystal structure was insignificant when it was more than 3h at 700℃.With the increase of x in Li x Mn 2 O 4 in the range of 0.6~1.0,the d 111 and lattice parameter a increased fi rst and then decreased.The electrochemical properties of nano-spinel LiMn 2 O 4 using as cathode material of lithium-ion battery were studied.The low di scharge capacity might be due to the irreversible capacity loss brou ght by the large surface area and latt ice vacancies of the nano-spinel.