Abstract
Hollow TiO2-X porous microspheres consisted of numerous well-crystalline nanocrystals with superior structural integrity and robust hollow interior were synthesized by a facile sol-gel template-assisted approach and two-step carbon-protected calcination method, together with hydrogenation treatment. They exhibit a uniform diameter of similar to 470 nm with a thin porous wall shell of similar to 50 nm in thickness. The Brunauer-Emmett-Teller (BET) surface area and pore volume are similar to 19 m(2)/g and 0.07 cm(3)/g, respectively. These hollow TiO2-X porous microspheres demonstrated excellent lithium storage performance with stable capacity retention for over 300 cycles (a high capacity of 151 mAh/g can be obtained up to 300 cycles at 1 C, retaining 81.6% of the initial capacity of 185 mAh/g) and enhanced rate capability even up to 10 C (222, 192, 121, and 92.1 mAh/g at current rates of 0.5, 1, 5, and 10 C, respectively). The intrinsic increased conductivity of the hydrogenated TiO2 microspheres and their robust hollow structure beneficial for lithium ion-electron diffusion and mitigating the structural strain synergistically contribute to the remarkable improvements in their cycling stability and rate performance.