Electrocatalysis of Fe‐N‐C Bonds Driving Reliable Interphase and Fast Kinetics for Phosphorus Anode in Sodium‐Ion Batteries

Abstract

Phosphorus exhibits high capacity and low redox potential, making it a promising anode material for future sodium‐ion batteries. However, its practical applications are confined by poor durability and sluggish kinetics. Herein, an innovative in‐situ electrochemically self‐driven strategy is presented to embed phosphorus nanocrystal (≈10 nm) into a Fe‐N‐C‐rich 3D carbon framework (P/Fe‐N‐C). This strategy enables rapid and high‐capacity sodium ion storage. Through a combination of experimental assistance and theoretical calculations, a novel synergistic catalytic mechanism of Fe‐N‐C is reasonably proposed. In detail, the electrochemical formation of Fe‐N‐C catalytic sites facilitates the release of fluorine in ester‐based electrolyte, inducing Na+‐conducting‐enhanced solid‐electrolyte interphase. Furthermore, it also effectively induces the dissociation energy of the P‐P bond and promotes the reaction kinetics of P anode. As a result, the unconventional P/Fe‐N‐C anode demonstrates outstanding rate‐capability (267 mAh g−1 at 100 A g−1) and cycling stability (72%, 10 000 cycles). Notably, the assembled pouch cell achieves high‐energy density of 220 Wh kg−1.

Molecular Engineering Enabling High Initial Coulombic Efficiency and Rubost Solid Electrolyte Interphase for Hard Carbon in Sodium‐Ion Batteries

“…A sharp peak at 685.1 eV can be observed, which is characteristic of the inorganic NaF, indicating the presence of NaF in the SEI (Figure 3j). [14c,15] Compared to HC, the SEI of DP‐HC is enriched in NaF, which is evidenced by the variation in the intensity of the NaF peak. Besides, the two fitted peaks of O 1s located at 531.5 and 536.4 eV are indexed as CO 3 2− and O−C=O (Figure 3k).…”

1D MnSe@carbon nanofiber as a high-rate anode for sodium-ion batteries: electrochemical and ex situ mechanistic investigation of Na+ charge storage

“…Such a low nanofiber thickness can lead to large surface area and improve high reversibility as well as better Coulombic efficiency during the electrochemical sodiation/desodiation process. 34–36…”

Accelerating High-Rate Li-Ion Storage in Graphite via a Thin-Layer Coating of Atomic Mo–NC

“…It should be noted that the R CT of Mo 1 –NC@Gr is less than half those of Mo 2 C–NC@Gr and Gr. This strongly implies that the atomically dispersed Mo species are of great importance for accelerating current exchange at Gr/solvent interfaces. , …”

“…This strongly implies that the atomically dispersed Mo species are of great importance for accelerating current exchange at Gr/solvent interfaces. 49,50 Symmetric cells were assembled to further investigate the charge transfer behavior at anode interfaces. As shown in Figure 4g, the galvanostatic charge/discharge curves of three samples are obtained at different areal currents, and the overpotentials for both charge and discharge of Mo 1 −NC@Gr and Mo 2 C−NC@Gr are significantly lower than those of pristine Gr, suggesting that the decoration of catalysts on the Gr interface is of great benefit for improving reaction kinetics.…”