Facile surface engineering of bio-waste derived amorphous carbon with SnO2 nanowires to enhance the efficacy of Li/Na storage

Abstract

Amorphous carbon is expected to be an excellent material for rechargeable battery anodes if the specific capacity can be enhanced by fabricating a composite with an appropriate material. To the contrary, SnO₂ exhibits a very high specific capacity as a Li/Na-ion battery anode due to its conversion-alloying mechanism, but low cycling stability confines its practical applications. Hence, we demonstrate the strategy of synthesizing a SnO₂ composite with non-activated carbon (NAC) derived from jute stick using facile wet chemical dispersion followed by annealing, which is a cost effective and scalable approach. The facile synthesis strategy proves to be beneficial for the uniform decoration of SnO₂ nanowires on the top of the NAC, which helps to compensate the volume expansion during the electrochemical reaction. The C/SnO₂ composite exhibits improved electrochemical performance compared to the NAC with a specific discharge/charge capacity of 1657/868 mA h g⁻¹ at 25 mA g⁻¹ specific current with high rate and stability as a Li-ion battery anode. Upon assembling the composite with C/LFP as a cathode, the full cell delivers the maximum energy density of 384 W h kg⁻¹ with an average voltage of 2.3 V. It also demonstrates Na-ion storage behavior with a specific charge capacity of 217 mA h g⁻¹ at 25 mA g⁻¹ specific current. Hence, the facile, scalable synthesis route and excellent battery performance of the aforementioned composite may endorse this pathway for the development of low-cost rechargeable battery anodes.