In‐depth insights into critical role of aromatic C(sp ² )–H on Li ⁺ storage

The development of high‐sloping‐capacity carbons enables the creation of high‐power lithium‐ion batteries and capacitors (LIBs/LICs). Among the various heteroatom‐doped carbon materials, hydrogen‐rich carbon appears to be a promising candidate due to its facile synthesis and high capacity for Li + storage. Nevertheless, conclusive data are still lacking to elucidate the fundamental function of the hydrogen‐terminated groups (C–H configuration) in Li + storage. Prof. Lian and his co‐workers have utilized an ion‐catalyzed self‐template method to synthesize the hydrogen‐rich carbon nanoribbon (HCNR) with high specific and rate capacity. The HCNR’s Li + storage mechanism is clarified by the use of in situ spectroscopy methods, which reveals that the sp 2 ‐hybridization of the protonated carbon atoms undergoes a highly reversible transition to sp 3 ‐hybridization for efficient Li + ions uptake (), contributing to the dominant high sloping capacity. This sloping characteristic points to a highly capacitance‐dominated storage process with fast kinetics, enabling better rate performance. This discovery provides mechanistic insights into the critical function of aromatic C(sp 2 )–H in enhancing Li + storage and creates new opportunities for the development of such sloping‐type carbons for high‐performance rechargeable batteries and capacitors.