Abstract
Ti-doped truncated octahedron LiTixMn2-xO4 nanocomposites were synthesized through a facile hydrothermal treatment and calcination process. By using spherical aberration-corrected scanning transmission electron microscopy (Cs-STEM), the effects of Ti-doping on the structure evolution and stability enhancement of LiMn2O4 are revealed. It is found that truncated octahedrons are easily formed in Ti doping LiMn2O4 material. Structural characterizations reveal that most of the Ti4+ ions are composed into the spinel to form a more stable spinel LiTixMn2−xO4 phase framework in bulk. However, a portion of Ti4+ ions occupy 8a sites around the {001} plane surface to form a new TiMn2O4-like structure. The combination of LiTixMn2−xO4 frameworks in bulk and the TiMn2O4-like structure at the surface may enhance the stability of the spinel LiMn2O4. Our findings demonstrate the critical role of Ti doping in the surface chemical and structural evolution of LiMn2O4 and may guide the design principle for viable electrode materials.
Highlights
Though several strategies have been proposed to obtain truncated octahedral structures [5,36,37,38], in this report we find that Ti doping is beneficial to synthesize a truncated octahedral shape
Ti-doped truncated octahedron LiMn2O4 samples were synthesized by a facile hydrothermal treatment and calcination process
Cs-STEM and chemical analysis techniques were carried out to reveal the underlying mechanism of Ti doping on the structure evolution and the stability enhancement of LiMn2O4 samples with different
Summary
Rechargeable lithium-ion batteries (LIBs) have been regarded as promising energy storage and conversion devices for wearable mobile devices, electric vehicles (EVs), hybrid electric vehicles (HEVs), and stationary energy storage wells [1,2,3]. Among the various lithium-ion battery cathode materials, spinel LiMn2 O4 is believed to hold huge potential for fulfilling the field-use requirements because of its good thermal stability, low cost, environmental friendliness, and three-dimensional channel structure [4,5,6]. The practical applications of LiMn2 O4 cathodes are restricted by the capacity fading during charge–discharge cycles, especially at elevated temperatures (≥ 55 ◦ C), which can be ascribed to the Mn dissolution and Jahn–Teller distortion [7,8]
Sign-in/Register to view highlights & summary Sign-in/Register to access full text options 
Free) 
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a call
