From Paper to Paper-like Hierarchical Anatase TiO2 Film Electrode for High-Performance Lithium-Ion Batteries

A paper-like self-standing film electrode composed of hierarchical mesoporous anatase TiO 2 was designed and prepared through a facile route of filter paper templating in combination with an additional deep hydrolysis treatment process. The specific surface area of hierarchical mesoporous TiO 2 increased to 155.6 m 2 g –1 compared to the sample without the additional deep hydrolysis, which is only 16.0 m 2 g –1 . The results are consistent with a simple model of sphere stacking which suggests that the rich mesopores were from the void space created by the TiO 2 stacking. By applying such film as binder-free electrode in lithium-ion batteries (LIBs), good rate performance was demonstrated, and the capacity was still 100 mA h g –1 even at the high rate of 20 C. The contributions of Li + insertion/extraction reaction and capacitive effect on the capacities were investigated by cyclic voltammetry and calculation. With the sweep rate increased from 0.1 to 10 mV s –1, the contributions of capacitive effects increased from 46% to 88% of the total capacities. The uniquely architectural TiO 2 film electrode showed excellent cycling performance at high rate of 10 C through 400 cycles. It highly promises as a new anode for thin-film batteries with versatile application fields.