Journal
ACS APPLIED MATERIALS & INTERFACES
Volume 7, Issue 33, Pages 18519-18529Publisher
AMER CHEMICAL SOC
DOI: 10.1021/acsami.5b06184
Keywords
surface modification; in situ generated aryl diazonium; wettability; olivine; cathode; lithium-ion battery
Funding
- Hydro-Quebec
- Natural Sciences and Engineering Research Council of Canada
- NSERC
Ask authors/readers for more resources
The grafting of benzene-trifluoromethylsulfonirnide groups on LiFePO4/C was achieved by spontaneous reduction of in situ generated diazonium ions of the corresponding 4-amino-benzene-trifluoromethylsulfonimide. The diazotization of 4-amino-benzene-trifluoromethylsulfonirnide was a slow process that required a high concentration of precursors to promote the spontaneous grafting reaction. Contact angle measurements showed a hydrophilic surface was produced after the reaction that is consistent with grafting of benzene-trifluoromethylsulfonimide groups. Elemental analysis data revealed a 2.1 wt % loading of grafted molecules on the LiFePO4/C powder. Chemical oxidation of the cathode material during the grafting reaction was detected by X-ray diffraction and quantified by inductively coupled plasma atomic emission spectrometry. Surface modification improves the wettability of the cathode material, and better discharge capacities were obtained for modified electrodes at high C-rate. In addition, electrochemical impedance spectroscopy showed the resistance of the modified cathode was lower than that of the bare LiFePO4/C film electrode. Moreover, the modified cathode displayed superior capacity retention after 200 cycles of charge/discharge at 1 C.
Authors
I am an author on this paper
Click your name to claim this paper and add it to your profile.
Reviews
Recommended
No Data Available