Carbon aerogel/SnO2 as an advanced anode for sodium-ion batteries

As the anode of sodium-ion batteries (SIBs), SnO2 has been attracted considerable attention due to its high theoretical specific capacity. However, these shortcomings of SnO2 anode seriously restrict its practical use for high-performance SIBs due to its poor conductivity, volume expansion and agglomeration of the active material during cycling. In this paper, carbon aerogel (CA) is a three-dimensional porous material with glucose as carbon source and freeze-dried hydrogel method is used to retain three-dimensional network structure by calcination. SnO2 is prepared by hydrothermal method with nanoparticles and distributed on the CA homogeneously to prepare CA/SnO2. The CA/SnO2 is prepared for SIB, in which CA can alleviate the problem of volume expansion and improve poor conductivity of SnO2 as a good carrier. Moreover, the porous structure of CA is beneficial to increase the contact between the electrolyte and the electrode, and accelerates the transmission speed of ions and electrons. Nano-sized SnO2 also contributes to cycle stability. The CA/SnO2 exhibits superior electrochemical performance and maintains a reversible discharge specific capacity of 235mAhg(-1) at a current density of 50mAg(-1) after 100 cycles.