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Abstract Increasing the specific capacity and cycle life of graphitic carbon anodes is crucial for realizing high-performance lithium ion batteries. Herein, we introduce a new class of graphitic carbon anodes comprising highly ordered three-dimensional nanostructures decorated with SnO 2 nanoparticles. The inch-scale, nanostructured graphitic carbon matrices are prepared by supported pyrolysis of epoxy templates patterned by advanced optical lithography. During the subsequent decoration process, the SnO 2 nanoparticles are densely formed on the matrix without agglomeration since the periodic nanostructured matrix provides a homogeneous site for nucleation and growth. The surface coverage of the decorated SnO 2 nanoparticles and the mass relative to the graphitic carbon are >80% and ∼50 wt%, respectively. The resulting nanostructured C/SnO 2 composite monoliths can be assembled solely into LIB coin cells without the aid of binders and conducting agents. The achieved specific capacity and retention are 692 mAh g−1 and 87.31% (at 70th cycle), respectively, which is superior to those of nanostructured carbon anodes prepared in a similar way. [ABSTRACT FROM AUTHOR]

Structural and electronic modification of titanium oxide (TiO 2 ) nanomaterials induced by the co-introduction of fully disordered glass phase and oxygen vacancies can lead to remarkable advances in the electrode performance in emerging energy storage systems. We report on the effective co-creation of fully amorphous nanofibers (NFs) composed of black TiO 2-x and conductive carbons throughout the NF structure, and evaluate the materials as potential anodes in sodium-ion batteries. The black TiO 2-x nanofiber is successfully fabricated by electrospinning a precursor solution followed by a two-step sequential thermal treatment in an air and reducing atmosphere. The NF electrode could deliver approximately two-fold higher 2nd discharge capacity and an excellent kinetic performance even under high rates compared to that delivered by anatase-structured white TiO 2 NFs used as reference, because of (i) an inherent free volume in the glass phase corresponding to the enlarged Na + sites, (ii) increased electrical conductivity (low bandgap) resulting from the presence of Ti 3+ , (iii) introduction of conductive carbon agents around the TiO 2-x domain, and (iv) one-dimensional NF feature allowing numerous Na + reaction sites at the electrochemical interface. We also elucidate the morphological and structural changes in the nanofibers after discharge and charge by ex-situ characterizations. [ABSTRACT FROM AUTHOR]