Core–Shell Structured N‐Doped Hollow Porous Carbon With NiMo‐Layered Double Hydroxide Nanosheets for High‐Performance Supercapacitor Electrodes

Layered double hydroxides (LDHs) have emerged as promising supercapacitor electrode materials owing to their exceptional theoretical specific capacitance and straightforward synthesis protocols. However, the two‐dimensional layered structure of LDHs makes them less conductive and susceptible to agglomeration. Recent research has focused on integrating LDHs with porous carbon matrices and metal–organic frameworks to enhance charge transport and mechanical integrity. In this study, nitrogen‐doped hollow porous carbons (NHCs)@NiMo‐LDH composites were fabricated by synthesizing NHC derived from Co‐zeolite imidazole framework‐67 via tannic acid etching and subsequent carbonization, followed by the in situ synthesis of NiMo‐LDH ultrathin nanosheets. The resulting hollow diamond‐shaped dodecahedral structure enhances ion diffusion and prevents LDH aggregation, achieving a capacitance density of 696 F g −1 with a constant current density of 1 A g −1 . The device combining NHCs@NiMo‐LDH with activated carbon delivers a specific energy of 54.3 Wh kg −1 while maintaining 825 W kg −1 power output, demonstrating 68.1% capacity retention through 10,000 electrochemical cycles.