High performance sodium storage of Fe-doped mesoporous anatase TiO2/amorphous carbon composite

Fe-doped mesoporous anatase TiO2/amorphous carbon composites (FC-TiO2) are synthesized by a wet chemistry process. With Fe-doping concentration increasing, the microstructures of FC-TiO2 change from prism to nanoparticle, and finally turns block structure. When used as anode materials for sodium ion batteries, the FC-TiO2 electrodes exhibit a maximum capacity of 304 mA h g(-1) at 0.1 A g(-1) after 50 cycles with good rate capability (198 mA h g(-1) at 2 A g(-1)). Three synergic effects can be attributed to the improved electrochemical performance of FC-TiO2: (1) the high iron doping could largely narrow the band gap and restrain the growth of TiO2 crystallite; (2) the carbon coating offers a beneficial conductivity environment; (3) the porous structure can shorten the electronic sodium ion pathway during cycling. Moreover, this synthesis method is very easy for mass production. Therefore, FC-TiO2 should be an attractive and promising candidate for anode material of SIBs. (C) 2016 Elsevier B.V. All rights reserved.