Synergistic Li/cu co-doping in Fe/Mn-based layered oxides for elevated voltage and activated anionic redox for high-energy sodium-ion batteries
Synergistic Li/cu co-doping in Fe/Mn-based layered oxides for elevated voltage and activated anionic redox for high-energy sodium-ion batteries
研究概述
以Li/Cu协同掺杂调控铁锰基层状钠电正极，抑制Mn主导的低电位反应、增强Fe高电位反应并激活可逆晶格氧氧化还原。原位XRD、XAS及计算支持该机制；优化正极容量171.0 mAh/g，能量密度502.7 Wh/kg，1 C循环200次保持75.6%。
谱图与表征信息
Fig. 3. Charge compensation mechanism of FM and LCFM during cycling. (a, b) Fe and Mn K-edge XANES spectra of FM at different states of charge (SOCs) during the first cycle. (c, d) Fe and Mn K-edge XANES spectra of LCFM at different SOCs during the first cycle. (e, f) Calculated average oxidation states of Fe and Mn in FM. (g, h) Calculated average oxidation states of Fe and Mn in LCFM. (i, j) O 1 s XPS spectra of FM and LCFM in the pristine state, charged to 4.2 V, and discharged to 2.0 V.