Spherical LiMn0.792Fe0.198Mg0.010PO4 nanocrystals, which are highly dispersed and encapsulated within the interstices of supergrowth (single-walled) carbon nanotubes (SGCNTs), were successfully synthesized by in situ material processing technology called "ultra-centrifuging (UC) treatment". TEM images of these LiMn0.792Fe0.198Mg0.010PO4/SGCNT composites suggest the direct attachment of the LiMn0.792Fe0.198Mg0.010PO4 nanocrystals (10-40 nm) onto the surface of highly conductive SGCNTs. Mg-doping brought out 10% increase of Li+ capacity in Mn sites with 200% increase of Li+ diffusivity and 50% decrease of electrical resistance owing to such peculiar "nano-nano LiMn0.792Fe0.198Mg0.010PO4/SGCNT composites". The synthesized LiMn0.792Fe0.198Mg0.010PO4/SGCNT composites overcome the inherent restrictions of one-dimensional diffusion and deliver a high electrochemical capacity density of ca. 54 mA h g-1 per composite (corresponding to 77 mA h g-1 per pure LiMn0.792Fe0.198Mg0.010PO4) at a high rate of 50 C, while showing excellent cycle life, retaining 84% of the initial capacity over 3000 cycles.
ASJC Scopus subject areas
- Renewable Energy, Sustainability and the Environment
- Materials Science(all)