A Bio-Inspired Nanotubular Na(2)MoO(4)/TiO(2) Composite as a High-Performance Anodic Material for Lithium-Ion Batteries

A train of bio-inspired nanotubular Na(2)MoO(4)/TiO(2) composites were synthesized by using a natural cellulose substance (e.g., commercial ordinary filter paper) as the structural template. The TiO(2) gel films were coated on the cellulose nanofiber surfaces via a sol-gel method firstly, followed with the deposition of the poly(diallyldimethylammonium chloride)/Na(2)MoO(4) (PDDA/Na(2)MoO(4)) bi-layers several times, through the layer-by-layer self-assembly route, yielding the (PDDA/Na(2)MoO(4))(n)/TiO(2)-gel/cellulose composite, which was calcined in air to give various Na(2)MoO(4)/TiO(2) nanocomposites containing different Na(2)MoO(4) contents (15.4, 24.1, and 41.4%). The resultant nanocomposites all inherited the three-dimensionally porous network structure of the premier cellulose substance, which were formed by hierarchical TiO(2) nanotubes anchored with the Na(2)MoO(4) layers. When employed as anodic materials for lithium-ion batteries, those Na(2)MoO(4)/TiO(2) nanocomposites exhibited promoted electrochemical performances in comparison with the Na(2)MoO(4) powder and pure TiO(2) nanotubes, which was resulted from the high capacity of the Na(2)MoO(4) component and the buffering effects of the TiO(2) nanotubes. Among all the nanotubular Na(2)MoO(4)/TiO(2) composites, the one with a Na(2)MoO(4) content of 41.4% showed the best electrochemical properties, such as the cycling stability with a capacity of 180.22 mAh g(−1) after 200 charge/discharge cycles (current density: 100 mA g(−1)) and the optimal rate capability.