Mesostructured niobium (Nb)-doped TiO₂-carbon (Nb-TiO₂-C) composites are synthesized by a hydrothermal process for application as anode materials in Li-ion batteries. The composites have a hierarchical porous structure with the Nb-TiO₂ nanoparticles homogenously distributed throughout the porous carbon matrix. The Nb content is controlled (0–10 wt%) to investigate its effect on the physico-chemical properties and electrochemical performance of the composite. While the crystalline/surface structure varied with the addition of Nb (d-spacing of TiO₂: 0.34–0.36 nm), the morphology of the composite remained unaffected. The electrochemical performance (cycle stability and rate capability) of the Nb-TiO₂-C composite anode with 1 wt% Nb doping improved significantly. First, a full cut-off potential (0–2.5 V vs. Li/Li⁺) of Nb-doped composite anode (1 wt%) provides a higher energy utilization than that of the un-doped TiO₂-C anode. Second, Nb-TiO₂-C composite anode (1 wt%) exhibits an excellent long-term cycle stability (100% capacity retention, 297 mAh/g at 0.5 C after 100 cycles and 221 mAh/g at 2 C after 500 cycles) and improved rate-capability (192 mAh/g at 5 C), respectively (1 C: 150 mA/g). The superior electrochemical performance of Nb-TiO₂-C (1 wt%) could be attributed to the synergistic effect of improved electronic conductivity induced by optimal Nb doping (1 wt%) and lithium-ion penetration (high diffusion kinetics) through unique pore structures.

通过水热法合成了介孔结构的掺铌（Nb）的TiO _2-碳（Nb-TiO ₂ -C）复合材料，并将其用作锂离子电池的负极材料。该复合材料具有分级的多孔结构，其中Nb-TiO ₂纳米颗粒均匀地分布在整个多孔碳基质中。控制Nb含量（0-10 wt％），以研究其对复合物的理化性质和电化学性能的影响。当添加Nb时晶体/表面结构发生变化（TiO _2的d间距：0.34-0.36 nm），复合材料的形貌保持不变。Nb-TiO的电化学性能（循环稳定性和速率能力）掺有1 wt％Nb的₂ -C复合阳极明显改善。首先，掺Nb的复合阳极（1 wt％）的完全截止电势（0-2.5 V vs. Li / Li ⁺）比未掺杂的TiO ₂ -C阳极具有更高的能量利用率。其次，Nb-TiO ₂ -C复合阳极（1 wt％）表现出优异的长期循环稳定性（100％的容量保持率，在100次循环后在0.5 C时为297 mAh / g，在500次循环后在2 C时为221 mAh / g ）和改进的速率能力（在5 C下为192 mAh / g）（1 C：150 mA / g）。Nb-TiO ₂的优异电化学性能-C（1 wt％）可以归因于最佳的Nb掺杂（1 wt％）和通过独特的孔结构的锂离子渗透（高扩散动力学）引起的电子电导率提高的协同效应。