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High-power lithium-ion batteries place high demands on the fast charging ability of electrode materials, while for the current graphite anode, it suffers from anisotropic and sluggish Li+ transport due to its small interlayer spacing. In addition, the large polarization at low lithiation potential at a high rate leads to Li+ deposition and side reactions of Li with the electrolyte. In this work, α-Al2O3 nanodots incorporated into aggregates of thin-layer graphite have been developed by facile high-energy ball milling of graphite and layer-structured pseudo-boehmite. By optimization, the ball-milled graphite/Al2O3 (BG/Al2O3) manifests a high reversible capacity of 344 mAh g–1 higher than the 98.7 mAh g–1 of graphite after 500 cycles at 1 A g–1 (∼2.7C) and 200 mAh g–1 higher than the 59.6 mAh g–1 of raw graphite at 3 A g–1 after 500 cycles. The wrinkled edges and expanded interlayer spacing generated by high-energy ball milling optimize the Li+ transport and accelerate reaction kinetics, contributing high pseudocapacitance and enabling fast charging ability. The α-Al2O3 nanodots can decrease the side reactions between the electrolyte and graphite electrode, contributing high cyclic stability. This study lays a foundation for the one-step mechanical force chemistry method to prepare highly stable fast-charging graphite anode materials for lithium-ion batteries.

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The control of polymorphism transition of Eu[Formula: see text] ion-doped [Formula: see text]-, [Formula: see text]-, [Formula: see text]- and [Formula: see text]-metastable alumina derived from boehmite is demonstrated by the sol–gel method through controlling the doping amount and firing temperature and the resultant luminescent properties are investigated. Nanosized boehmite ([Formula: see text]-AlOOH) particulates in boehmite sol effectively prevent the formation of impurity phases of EuAlO2 and Eu2O3. The polymorphic structures of the induction-fired xerogel samples in weak reductive atmosphere can be held to the room temperature upon cooling down naturally. The luminescence properties of Eu[Formula: see text] ions verify the polymorphic transitions from [Formula: see text]-, [Formula: see text]-, [Formula: see text]- to [Formula: see text]-Al2O3 that are featured with their broad emission peaks positions at 410, 450, 480 and 500 nm, respectively. It is believed that boehmite sol–gel by taking the nanosized [Formula: see text]-AlOOH particulates as seeds assisted the dispersion of precursor constituents and is effective to adjust the onset of polymorphic transition temperatures and luminescence properties.