Effect of carbon dimensions on the electrochemical performance of SnSe2 anode for Na-ion batteries

Abstract The emerging Na-ion batteries have attracted the world’s attention due to abundant resources and low cost. SnSe2 is a promising anode material with high capacity. To overcome the poor electronic conductivity and large volume expansion, different dimensional carbon, including Super P, carbon nanotube and graphene, are compositing with SnSe2 via ball milling. It is proved that 2 dimensional (2D) graphene could better improve the capacity, cycle stability, and reduce the charge transfer resistance. The conductive network of graphene accelerated both long-range and short-range charge transfer, which is better than that of others. Thus SnSe2/RGO sample delivers the highest specific capacity of 469 mAh g-1 at 50 mA g-1 and 145 mAh g-1 at 5 A g-1. This work reveals that the dimension of carbon is an important factor in materials design and performance improvement.