Ultra-High Initial Coulombic Efficiency Induced by Interface Engineering Enables Rapid, Stable Sodium Storage
Publication Name
Angewandte Chemie - International Edition
Abstract
High initial coulombic efficiency is highly desired because it implies effective interface construction and few electrolyte consumption, indicating enhanced batteries’ life and power output. In this work, a high-capacity sodium storage material with FeS nanoclusters (≈1–2 nm) embedded in N, S-doped carbon matrix (FeS /N,S-C) was synthesized, the surface of which displays defects-repaired characteristic and detectable dot-matrix distributed Fe-N-C/Fe-S-C bonds. After the initial discharging process, the uniform ultra-thin NaF-rich (≈6.0 nm) solid electrolyte interphase was obtained, thereby achieving verifiable ultra-high initial coulombic efficiency (≈92 %). The defects-repaired surface provides perfect platform, and the catalysis of dot-matrix distributed Fe-N-C/Fe-S-C bonds to the rapid decomposing of NaSO CF and diethylene glycol dimethyl ether successfully accelerate the building of two-dimensional ultra-thin solid electrolyte interphase. DFT calculations further confirmed the catalysis mechanism. As a result, the constructed FeS /N,S-C provides high reversible capacity (749.6 mAh g at 0.1 A g ) and outstanding cycle stability (92.7 %, 10 000 cycles, 10.0 A g ). Especially, at −15 °C, it also obtains a reversible capacity of 211.7 mAh g at 10.0 A g . Assembled pouch-type cell performs potential application. The insight in this work provides a bright way to interface design for performance improvement in batteries. 2 2 3 3 2 −1 −1 −1 −1 −1
Open Access Status
This publication is not available as open access
Funding Number
21671205
Funding Sponsor
National Natural Science Foundation of China