Hollow TiO2–X porous microspheres composed of well-crystalline nanocrystals for high-performance lithium-ion batteries
titania, hydrogenation, porous wall, hollow microspheres, lithium-ion battery
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 carbonprotected calcination method, together with hydrogenation treatment. They exhibit a uniform diameter of ~470 nm with a thin porous wall shell of ~50 nm in thickness. The Brunauer-Emmett-Teller (BET) surface area and pore volume are ~19 m2/g and 0.07 cm3/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.
Tsinghua University Press
Chun Wang,Faxing Wang,Yujuan Zhao,Yuhui Li,Qin Yue,Yupu Liu,Yong Liu,Ahmed A. Elzatahry,Abdullah Al-Enizi,Yuping Wu,Yonghui Deng,Dongyuan Zhao, Hollow TiO2–X porous microspheres composed of well-crystalline nanocrystals for high-performance lithium-ion batteries. NanoRes.2016, 9(1): 165–173