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Titanium niobium oxide (TNO) exhibits great potential as a lithium‐ion battery anode due to its high capacity, minimal volume change during cycling, and safe good operation characteristic enabled from its voltage profile. However, its intrinsically low electronic and ionic conductivity hinders its potential for practical applications. This work proposes a facile coprecipitation method to address these limitations by incorporating a nano‐macro structure and in situ Sn ion doping into bulk TNO. This approach ensures homogeneous integration of TNO precursors and the Sn dopant at a molecular level within the co‐precipitation nanoparticles. Additionally, the use of low toxicity solvents facilitate scalability of the synthesis process. Excellent rate capability, high reversible capacities, and good capacity retention are achieved simultaneously due to synergistic effects of the bulk doping, which expands the crystal volume and enhances Li+ diffusion, combined with abundant surface area of the nano‐macro structures. The specific capacity of Sn‐doped TNO nanospheres remains at 180 mAh/g at a high current density of 40 C (1 C=400 mA g−1), which is nearly four times higher than that of undoped samples. Furthermore, the cyclic voltammetry analysis at various scanning rates reveals an increased Li+ diffusion rate in Sn doped titanium niobium dioxide. [ABSTRACT FROM AUTHOR]

Mesoporous TiO2/C nanohybrids with large specific surface area and well‐defined pore size distribution are prepared by KOH activation treatment using dental resin monomers as solvent and carbon source. Super‐small sized TiO2 nanoparticles are uniformly distributed in porous carbon to realize a significant improvement of the electrochemical properties. The morphology, BET specific surface area and pore size distribution are characterized by SEM, TEM and N2 adsorption/desorption isotherm, respectively. The prepared mesoporous TiO2/C delivers a reversible capacity as high as 387 mAh/g after 100 discharge/charge cycles at 0.2 C current density (1 C=335 mA/g) in conjunction with a good rate capability (184, 70, and 92 mAh/g at 1, 2, and 5 C current densities, respectively). [ABSTRACT FROM AUTHOR]

Dual N‐doped TiO2/Si/C ternary nanohybrid has been successfully prepared via a facile solvothermal method. Polyethylene glycol (PEG) is applied to disperse TiO2 and silicon precursors. After polymerization with hexamethylene diisocyanate (HDI) and calcination, N‐doped TiO2 and carbon matrix are obtained. The contents of Si, TiO2 and C in N‐doped TiO2/Si/C are about 10 %, 72 % and 18 % respectively. N‐doped TiO2/Si/C shows an excellent electrochemical performance due to combined advantages of Si, TiO2 and C. The initial discharge/charge specific capacity of the N‐doped TiO2/Si/C is 658/548 mAh g−1 at a current of 0.1 A g−1 with a coulombic efficiency of 83 %. A reversible capacity of 538 mAh g−1 is achieved after 80 cycles. While at the high current of 5 A g1, the specific capacity of the N‐doped TiO2/Si/C can still reach 120 mAh g−1. Electrochemical impedance spectroscopy measurements prove the improved electric conductivity after N‐doping. [ABSTRACT FROM AUTHOR]