Porous TiO₂ conformal coating on carbon nanotubes as energy storage materials

Abstract The controllable synthesis of strongly coupled inorganic materials/carbon nanotubes (CNTs) hybrids represents a long-standing challenge for developing advanced catalysts and energy-storage materials. Here we report a simple sol-gel method for facile synthesis of TiO₂/CNTs hybrid. The porous anatase TiO₂ nanoparticles are uniformly coated on the CNTs conducting network, which leads to remarkably improved electrochemical performances such as exceptional cycling stability, good high rate durability, and reduced resistance. This hybrid exhibits a reversible capacity as high as 200 mA·h g^-1 at a current density of 0.1 A g^-1 as an anode in lithium-ion battery (LIB). As a supercapacitor (SC), it shows a specific supercapacitance of 145 F g^-1 in 0.5 M H₂SO₄ electrolyte, higher than that of the previously reported TiO₂ based supercapacitors. Moreover, this hybrid also exhibits excellent durability after 1000 cycles for both LIBs and SCs. Such superior performance and cycling durability demonstrate the reinforced synergistic effects between the porous TiO₂ and interweaved CNTs network, indicating a great application potential for such hybrid materials in high power LIBs and SCs.