摘要
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 crnB/g, respectively. These hollow TiOR_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 I 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 benefidal for lithium ion-electron diffusion and mitigating the structural strain synergistically contribute to the remarkable improvements in their cycling stability and rate performance.
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 crnB/g, respectively. These hollow TiOR_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 I 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 benefidal for lithium ion-electron diffusion and mitigating the structural strain synergistically contribute to the remarkable improvements in their cycling stability and rate performance.
基金
This work was supported by the National Basic Research Program of China （Nos. 2012CB224805 and 2013CB934104）, Shanghai Sci. ＆ Tech. Committee （No. 14JC1400700）, the National Natural Science Foundation of China （Nos. 21210004, 51372041, 51422202 and U1463206）, the innovation program （No. 13ZZ004）, the ＂Shu Guang＂ Project （No. 13SG02） supported by Shanghai Municipal Education Commission, Qatar University startup grant # QUSG-CAS-MST-14／15-1, and National Youth Top Talent Support Program of National High-level Personnel of Special Support Program. We extend our appreciation to the Deanship of Scientific Research at King Saud University for funding the work through the research group project No RGP-227.
