Development of SnO2@C nanocomposites derived from cassava residues as a green anode for advanced lithium-ion batteries

Abstract

In this report, nanocomposites of SnO₂ and carbon (SnO₂@C nanocomposites) were synthesized by a solution-based method combined with calcination at 500 °C in Ar for 1 or 2 h, utilizing SnCl₄·5H₂O and cassava residues as the Sn and C precursors, respectively. Due to this unique structure, high first-cycle charge capacities of 716.6 and 837.2 mAh g⁻¹ at 0.2 A g⁻¹ were achieved for SnO₂@C electrodes calcined for 1 h and 2 h, namely SnO₂@C_1H and SnO₂@C_2H, respectively. Furthermore, the SnO₂@C_1H electrode maintained a capacity of 777.7 mAh g⁻¹ after 200 cycles, with the coulombic efficiency approaching 100 % after the initial cycle. The rate capacity test also demonstrated that the high current density charging capability of the SnO₂@C electrodes was superior, showing capacities of 738.1 mAh g⁻¹ for SnO₂@C_1H and 631.2 mAh g⁻¹ for SnO₂@C_2H at 5 A g⁻¹. Last but not least, the pseudo behavior was also confirmed to be consistently higher at all scan rates, elucidating the fast-charging capability of the SnO₂@C electrodes. With the improved performance, the SnO₂@C_1H nanocomposite has demonstrated excellent electrochemical ability and is suitable for anode material of advanced lithium-ion batteries.