Self-assembled nanoporous rutile TiO2 mesocrystals with tunable morphologies for high rate lithium-ion batteries

Wulff-shaped and nanorod-like nanoporous mesocrystals constructed from ultrathin rutile TiO 2 nanowires were successfully fabricated for the first time in the presence of the surfactant sodium dodecyl benzene sulfonate (SDBS). SDBS played a key role in the homoepitaxial self-assembly process, in which titanate nanowires were used as the primary building blocks for forming mesocrystals accompanying with a simultaneous phase transition. The nanoporous rutile TiO 2 mesocrystals have a large surface area and were subjected to detailed structural characterization by means of X-ray diffraction (XRD), scanning and transmission electron microscopy (SEM/TEM) including high-resolution TEM (HRTEM) and selected area electron diffraction (SAED). Furthermore, the nanoporous rutile TiO 2 mesocrystals were applied as the electrode materials in rechargeable lithium-ion batteries and demonstrated a large reversible charge–discharge capacity, excellent cycling stability and high rate performance. These properties were attributed to the intrinsic characteristic of the mesoscopic structured TiO 2 with nanoporous nature and larger surface area (which favored fast Li-ion transport), as well as the presence of sufficient void space to accommodate the volume change.