Local Built‐In Electric Field Enabled in Carbon‐Doped Co3O4 Nanocrystals for Superior Lithium‐Ion Storage

In this work, a novel concept of introducing a local built‐in electric field to facilitate lithium‐ion transport and storage within interstitial carbon (C‐) doped nanoarchitectured Co3O4 electrodes for greatly improved lithium‐ion storage properties is demonstrated. The imbalanced charge distribution emerging from the C‐dopant can induce a local electric field, to greatly facilitate charge transfer. Via the mechanism of “surface locking” effect and in situ topotactic conversion, unique sub‐10 nm nanocrystal‐assembled Co3O4 hollow nanotubes (HNTs) are formed, exhibiting excellent structural stability. The resulting C‐doped Co3O4 HNT‐based electrodes demonstrate an excellent reversible capacity ≈950 mA h g−1 after 300 cycles at 0.5 A g−1 and superior rate performance with ≈853 mA h g−1 at 10 A g−1.