Novel sodium/lithium-ion anode material based on ultrathin Na ₂ Ti ₂ O ₄ (OH) ₂ nanosheet

Ultrathin Na2Ti2O4(OH)2 nanosheets of ∼8 nm thickness were prepared by a facile method for the first time. The resulting material was also used as a conducting agent and binder-free anode, both for sodium-ion batteries and lithium-ion batteries, for the first time. The Na2Ti2O4(OH)2 nanosheets exhibited excellent Na/Li-ion storage performance. A long-term cycling performance of the ultrathin Na2Ti2O4(OH)2 nanosheets of 120 mA h g(-1) at ∼10C was retained after 500 cycles for sodium-ion batteries, and 150 mA h g(-1) at ∼1C was kept after 500 cycles for lithium-ion batteries. By comparison, the Na-ion storage performance is much better than the Li-ion storage performance of the Na2Ti2O4(OH)2 nanosheets anode, because of the existence of Na in the Na2Ti2O4(OH)2 host.