Binding SnO2 nanoparticles onto carbon nanotubes with assistance of amorphous MoO3 towards enhanced lithium storage performance

Abstract

We report the synthesis of a novel SnO₂/MoO₃/carbon nanotubes (CNTs) hybrid (denote as SMC) via hydrothermally treating aqueous SnCl₄-Na₂MoO₄-CNTs suspension. The hydrolysis of SnCl₄ promotes the precipitation of Na₂MoO₄, resulting in the simultaneous coprecipitation of the amorphous MoO₃ and SnO₂ nanoparticles which attach onto the CNTs (Note that no MoOx is produced in the absence of SnCl₄). When used as anode materials for lithium ion batteries (LIBs), the as-prepared SMC hybrid delivers a high reversible capacities of 1032 and 887mAh/g after 50 cycles at current densities of 200 and 500mA/g, respectively, and still retains a reversible capacity of 496mAh/g even after 200 cycles at a higher rate of 2A/g, which shows much better lithium storage performance than that of the counterpart hybrid of SnO₂/CNTs (denote as SC, with only 569mAh/g after 50 cycles at 200mA/g). The enhanced electrochemical performance of SMC can be attributed to a synergistic effect, namely, MoO₃ not only confines SnO₂ nanoparticles onto the CNTs but also brings additional lithium storage capacity, while the flexible conductive CNT networks facilitate the charge transfer and electrolyte diffusion.

Keywords: Amorphous MoO(3); Binding effect; Carbon nanotubes; Enhanced lithium storage; SnO(2) nanoparticles.