TY - JOUR
T1 - Enhanced cycling stability through erbium doping of LiMn2O4 cathode material synthesized by sol-gel technique
AU - Zhao, Hongyuan
AU - Bai, Xiuzhi
AU - Wang, Jing
AU - Li, Dongdong
AU - Li, Bo
AU - Wang, Yashuang
AU - Dong, Li
AU - Liu, Binbin
AU - Komarneni, Sridhar
N1 - Publisher Copyright:
© 2018 by the authors.
Copyright:
Copyright 2018 Elsevier B.V., All rights reserved.
PY - 2018/8/29
Y1 - 2018/8/29
N2 - In this work, LiMn2-xErxO4 (x ≤ 0.05) samples were obtained by sol-gel processing with erbium nitrate as the erbium source. XRD measurements showed that the Er-doping had no substantial impact on the crystalline structure of the sample. The optimal LiMn1.97Er0.03O4 sample exhibited an intrinsic spinel structure and a narrow particle size distribution. The introduction of Er3+ ions reduced the content of Mn3+ ions, which seemed to efficiently suppress the Jahn-Teller distortion. Moreover, the decreased lattice parameters suggested that a more stable spinel structure was obtained, because the Er3+ ions in a ErO6 octahedra have stronger bonding energy (615 kJ/mol) than that of the Mn3+ ions in a MnO6 octahedra (402 kJ/mol). The present results suggest that the excellent cycling life of the optimal LiMn1.97Er0.03O4 sample is because of the inhibition of the Jahn-Teller distortion and the improvement of the structural stability. When cycled at 0.5 C, the optimal LiMn1.97Er0.03O4 sample exhibited a high initial capacity of 130.2 mAh g-1 with an excellent retention of 95.2% after 100 cycles. More significantly, this sample showed 83.1 mAh g-1 at 10 C, while the undoped sample showed a much lower capacity. Additionally, when cycled at 55 °C, a satisfactory retention of 91.4% could be achieved at 0.5 C after 100 cycles with a first reversible capacity of 130.1 mAh g-1.
AB - In this work, LiMn2-xErxO4 (x ≤ 0.05) samples were obtained by sol-gel processing with erbium nitrate as the erbium source. XRD measurements showed that the Er-doping had no substantial impact on the crystalline structure of the sample. The optimal LiMn1.97Er0.03O4 sample exhibited an intrinsic spinel structure and a narrow particle size distribution. The introduction of Er3+ ions reduced the content of Mn3+ ions, which seemed to efficiently suppress the Jahn-Teller distortion. Moreover, the decreased lattice parameters suggested that a more stable spinel structure was obtained, because the Er3+ ions in a ErO6 octahedra have stronger bonding energy (615 kJ/mol) than that of the Mn3+ ions in a MnO6 octahedra (402 kJ/mol). The present results suggest that the excellent cycling life of the optimal LiMn1.97Er0.03O4 sample is because of the inhibition of the Jahn-Teller distortion and the improvement of the structural stability. When cycled at 0.5 C, the optimal LiMn1.97Er0.03O4 sample exhibited a high initial capacity of 130.2 mAh g-1 with an excellent retention of 95.2% after 100 cycles. More significantly, this sample showed 83.1 mAh g-1 at 10 C, while the undoped sample showed a much lower capacity. Additionally, when cycled at 55 °C, a satisfactory retention of 91.4% could be achieved at 0.5 C after 100 cycles with a first reversible capacity of 130.1 mAh g-1.
UR - http://www.scopus.com/inward/record.url?scp=85052644601&partnerID=8YFLogxK
UR - http://www.scopus.com/inward/citedby.url?scp=85052644601&partnerID=8YFLogxK
U2 - 10.3390/ma11091558
DO - 10.3390/ma11091558
M3 - Article
C2 - 30158482
AN - SCOPUS:85052644601
VL - 11
JO - Materials
JF - Materials
SN - 1996-1944
IS - 9
M1 - 1558
ER -