Adjustable Dimensionality of Microaggregates of Silicon in Hollow Carbon Nanospheres: An Efficient Pathway for High-Performance Lithium-Ion Batteries.

Abstract

Silicon, as an anode candidate with great promise for next-generation lithium-ion batteries (LIBs), has drawn massive attention. However, the deficiencyies of tremendous volume change and intrinsic low electron/ion conductivity will hinder its further development. To cope with these bottlenecks, from the aspect of dimension design concept, the diverse dimensionality of microaggregates derived from cogenetic Si/C nano-building blocks was explored rather than the conventional strategies such as morphology control, structure design, and composition adjustment of Si/C. Herein, constructing silicon-carbon hybrid materials considering component dimensional variation and dimensional hybridization is beneficial to enhance lithium storage performance. Initiating from 0D silicon nanodots evenly immersed in the interior and skeleton of a hollow carbon shell (SHC) nanosphere, the 1D SHC nanospheres interconnected with nitrogen doping carbon necklace fiber, a 2D SHC nanospheres directional arranged plane, and a 3D SHC nanospheres self-aggregated microsphere will be elaborately and favorably designed and composed. Then, three different as-prepared dimensional materials deliver their inherent superiority in chemical, physical, and electronic properties containing 1D high aspect ratio, 2D fast electron/ion diffusion kinetics, and 3D efficient conductive networks, yielding effectively enhanced electrochemical performance, respectively.