화학공학소재연구정보센터
Journal of Power Sources, Vol.278, 630-638, 2015
Self-assembled lamellar alpha-molybdenum trioxide as high performing anode material for lithium-ion batteries
Self-assembled lamellar alpha-molybdenum trioxide (alpha-MoO3) has been prepared using facile polymer (polyvinyl pyrrolidone) assisted solvothermal method. Field-emission scanning electron microscopy (FESEM) studies reveal that the lamellar hexagonal particles are formed by close staking of 20-30 nm thin flakes (nanosheets). When used as lithium-ion battery electrode lamellar alpha-MoO3 shows superior electrochemical reversibility and excellent rate capability. For example after 50 cycles, a capacity value of 1027 mA h g(-1) can be extracted at 0.2C rate while at 2C rate it shows capacity of 700 mA h g(-1), which is higher than the theoretical capacity of conventional graphite anode. exsitu XRD and FESEM studies on electrochemically cycled samples show that the crystalline phase irreversibly changes to amorphous phase during the first discharge whereas the particle morphology remains unaltered even after 100 charge-discharge cycles. The superior electrochemical performance of alpha-MoO3 is attributed to its lamellar-like morphology which allows faster lithium ion diffusion in addition to buffering the volume changes during lithiation/de-lithiation. (C) 2014 Elsevier B.V. All rights reserved.