Fabrication of SnO2/pyrolytic carbon nanosphere via methods of precursor atomization and combustion as a high reversibility anode for sodium storage

Abstract This paper reported a SnO 2 /pyrolytic carbon nanosphere (SnO 2 -PCS), which is prepared via methods of precursor atomization and laser assistance combustion. Combined the advantages of nanocrystalline SnO 2 and pyrolytic carbon, samples show enhanced reversibility in sodium storage application. The SnO 2 -PCS prepared under an optimized condition (at oxygen concentrations of 5 vol%) shows the best electrochemical performance. In details, a high Coulombic efficiency of 67.3% with a discharge capacity of 997 mAh g –1 can be obtained in the first cycle, and then the Coulombic efficiency quickly increase to 98.2% in the third cycle and closed to 100% in further cycles. Meanwhile, samples show a high reversible capacity of 507 mAh g –1 at 50 mA g –1 after 250 cycles and a high rate capacity of 225 mAh g –1 at 1500 mA g –1 . Experimental results show that, the performance enhancement can be attribute to the pyrolytic carbon provide a reasonable surface area, enough volume change buffering and a good electric conductivity. This work demonstrated a promising high performance anode for Na-ion batteries, in the meantime, it provided a high efficient pathway to prepared SnO 2 /pyrolytic carbon nanocomposites through such fast synthesis method.