Cellulosic filter paper derived MoO3/TiO2 composites with variable micromorphologies as anode materials for lithium storage

MoO3-based anodes for lithium storage have attracted more attentions due to the relatively high specific capacity of 1117 mAh g–1 and good chemical stability. Compound MoO3 with other functional materials and construction of unique micromorphologies have been proved to be efficient strategies for improving the electrochemical performances of MoO3-based anodes. Herein, MoO3/TiO2 composites were successfully biosynthesized with different micromorphologies. In the preparation processes, the hydrothermal and solvothermal treatments were carried out successively in the presence of cellulosic filter paper as the biotemplate, followed by calcination of the as-obtained composites in air, resulting in the final MoO3/TiO2 composite materials. The two microstructures of the MoO3 microfiber with entire TiO2 nanoparticles coating and the MoO3 microrod formed by stacking the microsheets with loosely TiO2 nanoparticles covering were prepared under different pH values of the precursor. Compared with the bare MoO3 materials, the corresponding MoO3/TiO2 composites showed enhanced electrochemical performances as anode materials for lithium-ion batteries. Especially the MoO3/TiO2 composite with core-shell microfibrous structure derived from cellulosic filter paper presented relatively better test results for lithium storage, delivering an initial discharge capacity of 1297.6 mAh g−1 with the first Coulombic efficiency of 65.8%, and a reversible specific capacity of 403.6 mAh g−1 after 200 cycles. It is demonstrated that a well-defined TiO2 coating layer can effectively inhibit the volume variations of MoO3 matter in the lithiation/delithiation processes. Combined with the porous microfibrous structure that alleviates the stress, provides more reaction sites and reduces diffusion paths of lithium-ion, a promising MoO3-based anode material was achieved. This work provides a facile biotemplate-based strategy for the design and fabrication of metal oxide-based composites with adjustable microstructures for energy storage.