Hierarchically nanostructured carbon nanotube/polyimide/mesoporous Fe2O3 nanocomposite for organic-inorganic lithium-ion battery anode

Abstract

Integrating organic multiple-carbonyl polymers and inorganic mesoporous metal oxides on highly conductive carbon nanotubes is a promising strategy to manufacture high-performance lithium-ion battery anodes; however, developing multicomponent nanocomposites with a hierarchical architecture still remain challenging. Herein, we design and produce hierarchically nanostructured carbon nanotube (CNT)/polyimide (PI)/mesoporous Fe 2 O 3 (meso-Fe 2 O 3 /PI/CNT) ternary nanocomposite materials via a sequential assembly and high-temperature dehydration strategy, aiming to fabricate flexible PI-supported meso-Fe 2 O 3 stacked on a conductive CNT supporting skeleton. By controlling the linear PI mainchain through the comonomer composition, different PI assemblies can grow on the surface of CNT to anchor meso-Fe 2 O 3 nanoparticles as well as alleviate the structural strain resulting from the volume expansion of meso-Fe 2 O 3 in its phase conversion reaction. Considering the porosity and cavity, the mesoporous Fe 2 O 3 architecture can not only buffer its volume expansion but also accommodate a large number of electrolytes to promote Li + transport. In addition, the hierarchical architecture endows the meso-Fe 2 O 3 /PI/CNT nanocomposite materials with a high structural stability during the electrochemical process. Benefiting from these structural advantages, Li-ion batteries assembled with meso-Fe 2 O 3 /PI-EDA/CNT electrodes deliver high capacities of 708.9, 608.2, and 454.5 mAh g −1 at 0.1, 0.3, and 0.5 A g −1 , respectively. Even at a high current density of 1 A g −1 , a discharge capacity of 95.6 mAh g −1 is still obtained after 3000 cycles. This work provides a promising route to integrate multiple-carbonyl polymers and mesoporous metal oxides with the aim of developing multicomponent organic-inorganic composite anode for Li-ion battery. • Hierarchically tubular organic-inorganic nanocomposite anode from self-assembly-assisted fabrication technique is reported. • Polyimide assemblies with controllable architecture for organic anode material and strain buffer interlayer. • Fe 2 O 3 nanoparticle with mesoporous structures for inorganic anode material. • The organic-inorganic nanocomposite anode shows desirable lithium-ion battery performance.