Bottom-up Synthesis of Copper Fluoride Nanocomposites and Their Application to Rechargeable Li Batteries

Thursday, 28 May 2015: 08:40
Salon A-5 (Hilton Chicago)
J. Chun (POSTECH), Y. Kim (UNIST), and J. Lee (POSTECH)
Copper fluoride (CuF2) is one of the attractive cathode candidates for rechargeable Li batteries that have high theoretical operation potential (3.55 V vs. Li/Li+) and large specific capacity (528 mAh/g). However, synthesizing nanostructured CuF2, as well as harnessing its potential rechargeability, has been a challenge because of it inherent chemical and electrochemical properties. Only top-down approaches have been reported for down-sizing CuF2, and there are no reports on reversible electrochemical performance of CuF2 even at the first several cycles. Herein, we report a facile and versatile synthetic method for CuF2/mesoporous carbon nanocomposites and their application to the cathodes of rechargeable Li batteries. Through heat treatment with NH4F in a solventless system, CuF2 was easily synthesized from various copper precursors. CuF2 nanoparticles confined in mesoporous carbon exhibited not only superior specific capacity and rate capability at the first discharge in the normal coin-type cell, but also promising cycle performance in the solid-electrolyte-incorporated cell. To the best of our knowledge, this is the first report in which nanostructured CuF2 is synthesized using a bottom-up approach and successfully applied to rechargeable Li batteries.