Synthesis of Lithium Thin Film by Electrodeposition from Ionic Liquid

摘要

The synthesis of metallic lithium thin film from two ionic liquids, 1-ethyl-3-methylimidazoliuom bis(trifluoromethylsulfonyl) imide ([EMIM]Tf_2N) and 1-methyl-1-propylpiperidinium bis(trifluoromethanesulfonyl) amide (PP13Tf_2N) with lithium bis(trifluoromethanesulfonyl) imide (LiTFSI) as the lithium source was investigated. Cyclic voltammograms on a gold electrode showed the possibility of the electrodeposition of metallic lithium, and the reduction current in [EMIM]Tf_2N was higher than the value in PP13Tf_2N. The metallic lithium thin film could be synthesized on the gold electrode under potentiostatic conditions as confirmed by various analytical techniques including X-ray diffraction and scanning electron microscopy with energy-dispersive spectroscopy. The electrodeposited lithium surface was uniform without dendritic structures, no impurities were detected except for trace oxygen introduced during handling for the analyses.