Hierarchical TiO₂/C nanocomposite monoliths with a robust scaffolding architecture, mesopore–macropore network and TiO₂–C heterostructure for high-performance lithium ion batteries

Abstract

Engineering hierarchical structures of electrode materials is a powerful strategy for optimizing the electrochemical performance of an anode material for lithium-ion batteries (LIBs). Herein, we report the fabrication of hierarchical TiO2/C nanocomposite monoliths by mediated mineralization and carbonization using bacterial cellulose (BC) as a scaffolding template as well as a carbon source. TiO2/C has a robust scaffolding architecture, a mesopore-macropore network and TiO2-C heterostructure. TiO2/C-500, obtained by calcination at 500 °C in nitrogen, contains an anatase TiO2-C heterostructure with a specific surface area of 66.5 m(2) g(-1). When evaluated as an anode material at 0.5 C, TiO2/C-500 exhibits a high and reversible lithium storage capacity of 188 mA h g(-1), an excellent initial capacity of 283 mA h g(-1), a long cycle life with a 94% coulombic efficiency preserved after 200 cycles, and a very low charge transfer resistance. The superior electrochemical performance of TiO2/C-500 is attributed to the synergistic effect of high electrical conductivity, anatase TiO2-C heterostructure, mesopore-macropore network and robust scaffolding architecture. The current material strategy affords a general approach for the design of complex inorganic nanocomposites with structural stability, and tunable and interconnected hierarchical porosity that may lead to the next generation of electrochemical supercapacitors with high energy efficiency and superior power density.

Hierarchically Nanostructured Transition Metal Oxides for Lithium‐Ion Batteries

“…To further enhance the electrochemical performance of TiO 2 , TiO 2 /carbon composites have also been studied . Wang et al reported the synthesis of 3D hierarchical TiO 2 @C core–shell structure as anode material for LIBs .…”

Recent advances in the synthesis of hierarchically mesoporous TiO2 materials for energy and environmental applications

“…Employing various nanostructured mesoporous TiO 2 materials, especially for those with hierarchically porous structures as anodes for rechargeable LIBs, is popular [ 143 ]. For instance, hierarchically macro/mesoporous TiO 2 microparticles possess an excellent initial capacity of 235 and 202 mAh g −1 at 0.2 and 1 C, respectively [ 61 ].…”

Mesoporous TiO2/TiC@C Composite Membranes with Stable TiO2-C Interface for Robust Lithium Storage

“…Among the different kinds of TMOs, TiO 2 is an attractive material for LIBs owing to its natural abundance, low cost, and environmental benignancy ( Liu and Chen, 2014 , Liu et al., 2015a , Zhang et al., 2012 ). TiO 2 /C composite anode materials with various dimensions and structures have been fabricated, which include hierarchical TiO 2 /C nanocomposite monoliths ( Huang et al., 2016 ), ordered mesoporous TiO 2 /C nanocomposites ( Zeng et al., 2013 ), graphitic carbon conformal coating of mesoporous TiO 2 hollow spheres ( Liu et al., 2015b ), and mesoporous TiO 2 coating on flexible graphitized carbon ( Liu et al., 2016 ). However, all TiO 2 /C composites also suffer from severe structural collapse stemming from unstable TiO 2 -C interfaces.…”