Bioinspired Synthesis of Hierarchical Porous Graphitic Carbon Spheres with Outstanding High-Rate Performance in Lithium-Ion Batteries

摘要

Inspired by the biomineralization of unicellular diatoms, a biomimetic approach based on template (pluronic F127 micelle cluster)-induced self-assembly of alpha-cyclodextrin is developed to create hierarchical porous graphitic carbon spheres via hydrothermal treatment followed by pyrolysis. The as-obtained carbon spheres combine the features required for high-power electrode materials in lithium-ion batteries (LIBs), such as high degree of graphitization, large surface area with hierarchically distributed pore sizes as well as doping with heteroatoms, which synergistically contribute to their impressive electrochemical properties. When applied as an anode for LIBs, the carbon spheres exhibit high reversible capacity (ca. 700 mA h g(-1) at 50 mA g(-1)), good cycling stability, and remarkably outstanding high-rate performance (ca. 600, 450, and 290 mA h g(-1) obtained at a current density of 1, 10, and 30 A g(-1), respectively), which is among the best of present pure carbon materials for LIBs applications. The fabrication process is straightforward and cost-effective, providing a new methodology for the tailored design of carbon materials with enhanced power densities for energy storage applications.