Heterocoagulation 법으로 제조된 이차전지용 MWNT/SnO₂나노복합음극재의 전기화학적 특성

Abstract

Through the electrostatic interaction between the poly-diallydimethylammonium chloride (PDDA) modified Multi-walled carbon nanotube (MWNT) and SnO₂suspension in 1mM NaNo₃solution, MWNT-SnO₂nanocomposites (MSC) for anode electrodes of a Li-ion battery were successfully fabricated by colloidal heterocoagulation method. TEM observation showed that most of the SnO₂nanoparticles were uniformly deposited on the outside surface of the MWNT. Galvanostatic charge/ discharge cycling tests showed that MSC anodes exhibited higher specific capacities than bare MWNT and better cyclability than unsupported nano-SnO₂anodes. Also, after 20 cycles, the MSC anode fabricated by heterocoagulation method showed more stable cycle properties than the simply mixed MSC anode. These improved electrochemical properties are attributed to the MWNT, which adsorbs the mechanical stress induced from volume change and increasing electrical conductivity of the MSC anode, and suppresses the aggregation between the SnO₂nanoparticles.