title: Electrochemical Treatment for Effectively Tuning Thermoelectric Properties of Free-Standing Poly(3-methylthiophene) Films.
abstract: The degree of oxidation of conducting polymers has great influence on their thermoelectric properties. Free-standing poly(3-methylthiophene) (P3MeT) films were prepared by electrochemical polymerization in boron trifluoride diethyl etherate, and the fresh films were treated electrochemically with a solution of propylene carbonate/lithium perchlorate as mediator. The conductivity of the resultant P3MeT films depends on the doping level, which is controlled by a constant potential from -0.5 to 1.4 V. The optimum electrical conductivity (78.9 S cm(-1) at 0.5 V) and a significant increase in the Seebeck coefficient (64.3 μV K(-1) at -0.5 V) are important for achieving an optimum power factor at an optimal potential. The power factor of electrochemically treated P3MeT films reached its maximum value of 4.03 μW m(-1)  K(-2) at 0.5 V. Moreover, after two months, it still exhibited a value of 3.75 μW m(-1)  K(-2) , and thus was more stable than pristine P3MeT due to exchange of doping ions in films under ambient conditions. This electrochemical treatment is a significant alternative method for optimizing the thermoelectric power factor of conducting polymer films.
authors.affiliation: Jiangxi Engineering Laboratory of Waterborne Coatings, Jiangxi Science and Technology Normal University, Nanchang, 330013, P. R. China.
authors.forename: Yongjing
authors.initials: Y
authors.lastname: Hu
authors.affiliation: Jiangxi Engineering Laboratory of Waterborne Coatings, Jiangxi Science and Technology Normal University, Nanchang, 330013, P. R. China.
authors.forename: Danhua
authors.initials: D
authors.lastname: Zhu
authors.affiliation: Jiangxi Engineering Laboratory of Waterborne Coatings, Jiangxi Science and Technology Normal University, Nanchang, 330013, P. R. China.
authors.forename: Zhengyou
authors.initials: Z
authors.lastname: Zhu
authors.affiliation: Jiangxi Engineering Laboratory of Waterborne Coatings, Jiangxi Science and Technology Normal University, Nanchang, 330013, P. R. China.
authors.forename: Endou
authors.initials: E
authors.lastname: Liu
authors.affiliation: Jiangxi Engineering Laboratory of Waterborne Coatings, Jiangxi Science and Technology Normal University, Nanchang, 330013, P. R. China.
authors.forename: Baoyang
authors.initials: B
authors.lastname: Lu
authors.affiliation: Jiangxi Engineering Laboratory of Waterborne Coatings, Jiangxi Science and Technology Normal University, Nanchang, 330013, P. R. China. xujingkun@tsinghua.org.cn.
authors.forename: Jingkun
authors.initials: J
authors.lastname: Xu
authors.affiliation: Jiangxi Engineering Laboratory of Waterborne Coatings, Jiangxi Science and Technology Normal University, Nanchang, 330013, P. R. China.
authors.forename: Feng
authors.initials: F
authors.lastname: Zhao
authors.affiliation: State Key Laboratory for Marine Corrosion and Protection, Luoyang Ship Material Research Institute, Qingdao, 266101, P. R. China.
authors.forename: Jian
authors.initials: J
authors.lastname: Hou
authors.affiliation: Jiangxi Engineering Laboratory of Waterborne Coatings, Jiangxi Science and Technology Normal University, Nanchang, 330013, P. R. China.
authors.forename: Huixuan
authors.initials: H
authors.lastname: Liu
authors.affiliation: Jiangxi Engineering Laboratory of Waterborne Coatings, Jiangxi Science and Technology Normal University, Nanchang, 330013, P. R. China. f.x.jiang@live.cn.
authors.forename: Fengxing
authors.initials: F
authors.lastname: Jiang
keywords: doping level; electrochemistry; polymers; thermoelectrics; thin films