Molecular Design Strategy for Ordered Mesoporous Stoichiometric Metal Oxide

摘要

A molecular design strategy is used to construct ordered mesoporous Ti3+-doped Li4Ti5O12 nanocrystal frameworks (OM-Ti3+-Li4Ti5O12) by the stoichiometric cationic coordination assembly process. Ti4+/Li+-citrate chelate is designed as a new molecular precursor, in which the citrate can not only stoichiometrically coordinate Ti4+ with Li+ homogeneously at the atomic scale, but also interact strongly with the PEO segments in the Pluronic F127. These features make the co-assembly and crystallization process more controllable, thus benefiting for the formation of the ordered mesostructures. The resultant OM-Ti3+-Li4Ti5O12 shows excellent rate (143 mAh g(-1) at 30 C) and cycling performances (<0.005 % fading per cycle). This work could open a facile avenue to constructing stoichiometric ordered mesoporous oxides or minerals with highly crystalline frameworks.