ABSTRACT
This study introduced a carbon-free electrode for Li-O2 cells with the aim of suppressing the side reactions activated by
carbon material. Micro-particles of poly(3,4-ethylenedioxythiophene) (PEDOT), a conducting polymer, were used as the
base material for the air electrode of Li-O2cells. The PEDOT micro-particles were treated with H2SO4 to improve their electronic
conductivity, and LiBr and CsBr were used as the redox mediators to facilitate the dissociation of there action products
in the electrode and reduce the over-potential of the Li-O2 cells. The capacity of the electrode employing PEDOT
micro-particles was significantly enhanced via H2SO4 treatment, which is attributed to the increased electronic conductivity.
The considerable capacity enhancement and relatively low over-potential of the electrode employing H2SO4-treated
PEDOT micro-particles indicate that the treated PEDOT micro-particles can act as reaction sites and provide storage space
for the reaction products. The cyclic performance of the electrode employing H2SO4-treated PEDOT micro-particles was
superior to that of a carbon electrode. The results of the Fourier-transform infrared spectroscopic analysis showed that the
accumulation of residual reaction products during cycling was significantly reduced by introducing the carbon-free electrode
based on H2SO4-treated PEDOT micro-particles, compared with that of the carbon electrode. The cycle life was
improved owing to the effect of the redox mediators. The refore, the use of the carbon -free electrode combined with redox
mediators could realize excellent cyclic performance and low over-potential simultaneously.
Author
Seon Hye Yoon, Jin Young Kim, and Yong Joon Park*
Department of Advanced Materials Engineering, Kyonggi University, 154-42, Gwanggyosan-Ro, Yeongtong-Gu, Suwon-Si,
Gyeonggi-Do, 443-760, Republic of Korea
|
