Regulatable 3D graphene aerogel as robust platform for sodium ion storage devices

The rise of Na-storage devices has imposed more stringent demands on storage electrode materials with large capacity, long service life, and fast rate capability. However, the application of electrode material is still hampered by its poor electrical conductivity and severe volume expansion. Herein, the reduced graphene oxide-based composite aerogel (rGO gel) is fabricated by implementing a self-shrinking strategy and leveraging the columnar support effect of one-dimensional nano-gaskets (T-Nb 2 O 5 and CNT). Benefiting from the synergistic effect of nano-gaskets and pore structure design, the composite electrode enhances the mechanical strength while buffering the volume change of the active materials. The well-connected conductive network not only promotes the diffusion of Na + but also provides abundant accessible active sites. Therefore, a half-cell assembled using rGO/T-Nb 2 O 5 as working electrode achieves maximum specific capacity of 546.5  mAh g −1 at 0.1 A g −1 . Moreover, the constructed 3D rGO/T-Nb 2 O 5 //rGO/CNT sodium-ion hybrid supercapacitor delivers a mass specific capacitance of 96.5F g −1 at the current density of 2.0 A g −1 . In addition, the high mass energy density of 66.2 Wh kg −1 and power density of 2225 W kg −1 are demonstrated. This work provides a novel structural design strategy for advancing high-performance Na-storage devices.