No abstract

No abstract

A novel synthetic method of fine particles of highly pure Li 4 Ti 5 O 12 with the smallest possible particle size was proposed. A stoichiometric mixture of CH 3 COOLi . 2H 2 O and anatase fine particles of ca. 50 nm was calcined at 773 K to obtain an intermediate, comprising Li 2 TiO 3 and unreacted titania. The intermediate was then intensively milled by a planetary ball mill for 1 h. After adding an amino acid, glycine, alanine (ALA), or L-phenylalanine (PHE), the mixture was further milled under a milder condition for another 3 h and subjected to a second calcination at 973 K for 1 h to obtain Li 4 Ti 5 O 12 with a phase purity above 97%. When we used ALA or PHE as an additive, the microscopically determined average particle size of Li 4 Ti 5 O 12 was 70710 nm. The mechanisms and significance of the present two-step calcination with mechanical activation and addition of an amino acid to the intermediate were discussed in terms of the topotactic nature of transformation between the two layer-structured species:

No abstract

No abstract