Comparative Study of Onion-like Carbons Prepared from Different Synthesis Routes towards Li-Ion Capacitor Application

Li-ion capacitors (LIC) have emerged as a promising hybrid energy storage system in response to increasing demands. However, achieve excellent LIC performance at high rates, along with cycling stability, an alternative anode graphite is needed. Porous high-surface-area carbons, such onion-like carbons (OLCs), been recently found hold potential high-rate-capable anodes. systematic understanding of their synthesis route and morphology lacking. In this study, OLCs prepared from self-made metal organic frameworks (MOFs) Fe-BTC Fe-MIL100 by simple pyrolysis method were compared obtained via high-temperature annealing nanodiamonds. The LICs produced achieved maximum density 243 Wh kg−1 power 20,149 W kg−1. Furthermore, capacitance retention 78% after 10,000 cycles was demonstrated. MOF-derived surpassed the nanodiamond-derived OLCs. We determined impact MOF precursor structure on resulting OLC properties, well electrochemical performance. Thus, offer significant toward high-performance material for LICs, enabling control over morphology, easy scalability industrial implementation.