α-Mn2O3 nanowires coated with conductive polymer for Li-ion battery anode materials : Synthesis, characterization, and applications

Abstract

Transition metal oxides have been considered as promising lithium storage materials that undergo a conversion reaction with Li ion, exhib-iting high specific capacity. Among them, manganese oxides have high capacity compared to other metal oxides, and also their costs are inex-pensive. However, capacity fading during cycling is the most serious obstacle for their commercialization. To slove the problems, poly(3,4-ethylenedioxythiophene) polystyrene sulfonate (PEDOT:PSS) was coated onto α-Mn2O3 nanowires while maintaining the structure of α-Mn2O3. PEDOT:PSS on the α-Mn2O3 reduced the resistance of the surface and protected the surface electron channels from the pulverization effect of the charge–discharge operation. α-Mn2O3/PEDOT:PSS showed excellent cyclability with a reversible capacity of 1450 mAh·g-1 after 200 cycles at a current density of 100 mA·g-1. An increase in ca-pacity was observed with continuous cycling, which may be attributed to further oxidation of the manganese species and a reversible reaction of the gel-like polymer on the manganese surface. The results demon-strate that PEDOT:PSS enhances the electrochemical activity by providing electron channels and prevents pulverization caused by the charge and discharge process.