Cabbage‐Inspired Graphene Aerogel Microspheres as Efficient Micro‐Reactors for High‐Yield Production of Short Carbon Nanotubes Toward Li + Battery

ABSTRACT Lithium‐ion batteries (LiBs) face critical challenges with graphite anodes, including limited theoretical capacity and sluggish Li + diffusion kinetics leading to safety risks. Short carbon nanotubes (CNTs) offer compelling advantages due to shortened Li + diffusion pathways and abundant defect‐mediated active sites, yet scalable fabrication remains hindered by harsh preparation processes or low yield/purity. Herein, we report an innovative spatially confined CNTs growth strategy that utilizes cabbage‐inspired graphene aerogel microspheres as efficient micro‐reactors for high‐yield production of defect‐rich shortened CNTs. The unique aerogel microspheres with hierarchical pore architecture simultaneously maximizes the dispersion/exposure of nano‐catalysts of metal, facilitates rapid propylene (C 3 H 6 ) gas diffusion, and physically confines the CNTs longitudinal growth, enabling an unprecedented growth yield of 385.58 gg − 1 cat in 1 h. The resulting short CNTs demonstrate superior LiBs anode performances compared with commercial graphite, exhibiting a high specific capacity of 468.73 mAhg − 1 and maintaining a great Coulombic efficiency of 98% at 0.2 C even after 100 cycles. This work develops a generalizable confined‐growth paradigm for synthesizing advanced nanocarbons towards energy storage and sustainable valorization of hydrocarbons.