Lamellar sodium titanium silicate assembled by nanostrips decorated with N-rich 3D carbon for sodium dual-ion batteries

Abstract

Sodium dual-ion batteries have received tremendous attention owing to their appealing operating voltage (i.e. >4.0 V) and eco-friendly features. However, the exploitation of efficient sodium ion storage anode materials is one of the keys for driving the application of sodium dual-ion batteries in the grid-scale energy storage. Herein, a lamellar sodium titanium silicate (NTSO) woven by plentiful nanostrips grown in situ on the surface of N-rich 3D carbon has been prepared via a convenient synthetic strategy. Based on the synergistic effect both micro-nano composite spatial structure and energy storage mechanism based on conversion reaction of material bulk phase, the NTSO/3DC-N composite as anode delivers a high special capacity of 540.6 mAh/g at 0.05 A/g and 163.1 mAh/g at 5.0 A/g in sodium ion half-cell. More impressively, the sodium dual-ion batteries built with NTSO/3DC-N as anode and a N-rich 3D carbon as cathode exhibits a high reversible capacity of about 123.6 mAh/g at 0.05 A/g. The elaborate designing an interconnecting framework composed of layered titanium silicate sodium and heterogeneous atom doping carbon substrate provides a generally applicable strategy for enhancing the anode performance of sodium dual-ion batteries.