Structural and electrochemical properties of the Li2FeP2O7/C composite prepared using soluble methylcellulose

JOURNAL OF ALLOYS AND COMPOUNDS

卷:786

Article

Jugovic, Dragana¹  Mitric, Miodrag²  Milovic, Milos¹  Ivanovski, Valentin N.²  Skapin, Sreco³  Dojcinovic, Biljana⁴  Uskokovic, Dragan¹ 

[1] Inst Tech Sci SASA, Knez Mihailova 35-4, Belgrade 11000, Serbia

[2] Univ Belgrade, Vinca Inst Nucl Sci, POB 522, Belgrade 11001, Serbia

[3] Jozef Stefan Inst, Jamova 39, SI-1000 Ljubljana, Slovenia

[4] Univ Belgrade, Inst Chem Technol & Met, Njegoseva 12, Belgrade 11000, Serbia

关键词: Energy storage materials;    Crystal structure;    Electrochemical reactions;    X-ray diffraction;    Mossbauer spectroscopy;   

DOI  :  10.1016/j.jallcom.2019.01.392

来源: Elsevier

【 摘 要 】

A new method involving the homogeneous dispersion of precursor compounds inside a methylcellulose matrix is used for the synthesis of a composite powder of Li2FeP2O7 and carbon. The properties of carbon-containing and carbon-free powders are studied by X-ray powder diffraction (XRD) including Rietveld refinement, Mossbauer spectroscopy, Fourier transform infrared spectroscopy (FTIR), field emission scanning electron microscopy (FESEM), galvanostatic cycling, and electrochemical impedance spectroscopy (EIS). The structure of both powders is refined in a monoclinic framework (space group P2(1)/c). The structural refinement and Mossbauer spectroscopy reveal different degrees of partial occupancy of mixed-occupied sites by lithium. Electrochemical measurements show that the in situ formation of carbon improves capacity (90% of 1-electron theoretical capacity) through decreased charge-transfer resistance. (C) 2019 Elsevier B.V. All rights reserved.

【 授权许可】

Free