Porous Carbon Nanorods Induced by Electrostatically Assembling Carbon Quantum Dots Within the Confined Hollow Space of Halloysite for Lithium‐Ion Battery Anodes

Abstract Halloysite nanotubes (HNTs) have hollow tubular structures and oppositely charged inner and outer surfaces, providing unique platforms for materials synthesis. Herein, porous carbon nanorods (CNRs) are synthesized using a vacuum liquid phase impregnation coupled with carbonization strategy, where carbon quantum dots serve as building blocks and HNTs act as nanoreactors. The synthesized CNRs feature a rod‐like carbon framework with high graphitization and abundant oxygen‐containing functional groups, and possess a hierarchical porous structure with large specific surface area (1187.9 m 2 ·g −1 ) and large pore volume (1.606 cm 3 ·g −1 ). The prepared CNRs applied as anode for lithium‐ion batteries exhibits a superior rate capability with high reversible capacities of 167 mAh·g −1 at 5000 mA·g −1 and present outstanding cycle stability of 593 mAh·g −1 after 1000 cycles at 1000 mA·g −1 . Density functional theory calculations indicate that the oxygen‐containing functional groups enhance Li atoms adsorption on graphene. Among these, the carboxyl group provides the greatest enhancement, with the maximum adsorption energy reaching −2.02 eV. Particularly, coupling CNRs with an LiNi 1/3 Co 1/3 Mn 1/3 O 2 cathode in a full cell further demonstrates the high electrochemical performance, underscoring the practical potential of these CNRs. This work opens new opportunities for the fabrication of 1D nanostructures with enhanced stability and durability for energy storage applications.