Manipulating Adsorption–Insertion Mechanisms in Nanostructured Carbon Materials for High‐Efficiency Sodium Ion Storage

Hard carbon is one of the most promising anode materials for sodium‐ion batteries, but the low Coulombic efficiency is still a key barrier. In this paper, a series of nanostructured hard carbon materials with controlled architectures is synthesized. Using a combination of in situ X‐ray diffraction mapping, ex situ nuclear magnetic resonance (NMR), electron paramagnetic resonance, electrochemical techniques, and simulations, an “adsorption–intercalation” mechanism is established for Na ion storage. During the initial stages of Na insertion, Na ions adsorb on the defect sites of hard carbon with a wide adsorption energy distribution, producing a sloping voltage profile. In the second stage, Na ions intercalate…

• UD
  U.S. Department of Energy
• NN
  National Natural Science Foundation of China

  Awards: 21273090, 21333007, 21373155
• BE
  Basic Energy Sciences

  Award: KC020105‐FWP12152