Multi-walled carbon nanotubes (CNTs)@TiO₂ composites with different contents of CNTs were prepared by employing solvothermal process using ethanol-glycerol mixture as solvent and subsequent calcination. The role of glycerol during solvothermal process was discussed and the microstructures of the as-prepared CNTs@TiO₂ composites were characterized by scanning electron microscopy, high-resolution transmission electron microscopy and X-ray diffraction. The results indicate glycerol is one of the solvothermal reactants and also play an important role for the coating of TiO₂ particles on the surface of CNTs because of its high viscosity. Moreover, with the increasing of the content of CNTs in composites, the surface areas of composites increase and TiO₂ layer becomes more uniform. Notably, CNTs@TiO₂ composites with 42 wt% CNTs have a specific surface area of 265.7 m² g⁻¹, and exhibit excellent high-rate performance and cyclic stability. Their specific capacities at 1C, 2C, 5C, 10C, 20C, 30C and 40C are 248, 228, 225, 212, 200, 194 and 191 mAh·g⁻¹, respectively. Even at 50C and 60C, their specific capacities are still as high as 187 and 184 mAh·g⁻¹, respectively. Moreover, 90.1% of the reversible capacity is retained after 1000 cycles at 10C. The excellent performance can be ascribed to the electronic and ionic rapid conductive network formed by CNTs in composites and the synergistic contribution from pseudocapacitance.

采用溶剂热法，以乙醇-甘油混合物为溶剂，经煅烧制备了碳纳米管含量不同的多壁碳纳米管@TiO ₂复合材料。讨论了甘油在溶剂热过程中的作用，并通过扫描电子显微镜，高分辨率透射电子显微镜和X射线衍射对制备的CNTs @ TiO ₂复合材料的微观结构进行了表征。结果表明，甘油是溶剂热反应物之一，并且由于其高粘度，还对TiO ₂颗粒在CNT表面的涂层起着重要作用。此外，随着复合材料中碳纳米管含量的增加，复合材料的表面积增加，TiO₂层变得更加均匀。值得注意的是，具有42wt％的CNT的CNTs @ TiO ₂复合材料具有265.7m ² g ^-1的比表面积，并且表现出优异的高速率性能和循环稳定性。它们在1C，2C，5C，10C，20C，30C和40C的比容量分别为248、228、225、212、200、194和191 mAh·g ^-1。即使在50℃和60℃下，它们的比容量仍高达187和184mAh·g ^-1， 分别。而且，在10℃下1000次循环后，保留了90.1％的可逆容量。优异的性能可以归因于复合材料中CNTs形成的电子和离子快速导电网络，以及伪电容的协同作用。