Bridging 1D Inorganic and Organic Synthesis to Fabricate Ultrathin Bismuth-Based Nanotubes with Controllable Size as Anode Materials for Secondary Li Batteries.

The growth of ultrathin 1D inorganic nanomaterials with controlled diameters remains challenging by current synthetic approaches. A polymer chain templated method is developed to synthesize ultrathin Bi O CO nanotubes. This formation of nanotubes is a consequence of registry between the electrostatic absorption of functional groups on polymer template and the growth habit of Bi O CO . The bulk bismuth precursor is broken into nanoparticles and anchored onto the polymer chain periodically. These nanoparticles react with the functional groups and gradually evolve into Bi O CO nanotubes along the chain. 5.0 and 3.0 nm tubes with narrow diameter deviation are synthesized by using branched polyethyleneimine and polyvinylpyrrolidone as the templates, respectively. Such Bi O CO nanotubes show a decent lithium-ion storage capacity of around 600 mA h g at 0.1 A g after 500 cycles, higher than other reported bismuth oxide anode materials. More interestingly, the Bi materials developed herein still show decent capacity at very low temperatures, that is, around 330 mA h g (-22 °C) and 170 mA h g (-35 °C) after 75 cycles at 0.1 A g , demonstrating their promising potential for practical application in extreme conditions.