Anion Size Effect of Ionic Liquids in Tuning the Thermoelectric and Mechanical Properties of PEDOT:PSS Films through a Counterion Exchange Strategy

Li，Qikai1,2,3; Zhou，Qing1,2,4; Xu，Wangping5,6; Wen，Long1,2; Li，Jun1,2; Deng，Biao1,2; Zhang，Jiajia1,2; Xu，Hu5; Liu，Weishu1,2

2022-06-22

10.1021/acsami.2c05591

ACS applied materials & interfaces   Impact Factor & Quartile

1944-8252

Poly(3,4-ethylene dioxythiophene):poly(styrenesulfonic acid) (PEDOT:PSS) thermoelectric thin films have attracted significant interest due to their solution-processable manufacturing. However, molecular-level tuning or doping is still a challenge to synergistically boost their thermoelectric performance and mechanically stretchable capabilities. In this work, we report a counterion exchange between ionic liquid bis(x-fluorosulfonyl) amide lithium (Li:nFSI, n = 1, 3, 5) with different sizes of anions and a PEDOT:PSS-induced bipolaron network, which significantly boosted the thermoelectric power factor from 0.8 to 157 μW m K-2 at 235 °C and the maximum tensile strain from 3% to over 30%. The π-π* stacking of the PEDOT polymer chains was fine-tuned by the hydrophobic anions of nFSI-, providing a technical route for constructing a bipolaron network and inducing the transition from hopping transport to band-like transport. Furthermore, we found that the stretchable capabilities, that is, εmax, were connected to the gelation time of the PEDOT:PSS-Li:nFSI aqueous solution. Thus, more fluorine-containing groups resulted in longer gelation times and higher εmax values, which significantly improved the processability of the solution-derived films.

flexibility gelation point hopping to band-like transport ionic liquids PEDOT:PSS thermoelectric

EI

English

First

20222712324825

Amides ; Ion exchange ; Ionic liquids ; Semiconductor doping ; Thermoelectric power

Semiconducting Materials:712.1 ; Chemical Reactions:802.2 ; Chemical Products Generally:804 ; Organic Compounds:804.1

2-s2.0-85132455681

Scopus

1.Department of Materials Science and Engineering,Southern University of Science and Technology,Shenzhen,518055,China
2.Shenzhen Engineering Research Center for Novel Electronic Information Materials and Devices,Southern University of Science and Technology,Shenzhen,518055,China
3.Department of Mechanical Engineering,University of Hong Kong,Hong Kong,Pokfulam Road,999077,China
4.School of Science,Minzu University of China,100081,China
5.Department of Physics,Guangdong Provincial Key Laboratory of Computational Science and Material Design,Shenzhen Key Laboratory of Advanced Quantum Functional Materials and Devices,Southern University of Science and Technology,Shenzhen,518055,China
6.Hunan Institute of Advanced Sensing and Information Technology,Xiangtan University,Xiangtan,411105,China

Li，Qikai,Zhou，Qing,Xu，Wangping,et al. Anion Size Effect of Ionic Liquids in Tuning the Thermoelectric and Mechanical Properties of PEDOT:PSS Films through a Counterion Exchange Strategy[J]. ACS applied materials & interfaces,2022,14(24):27911-27921.

Li，Qikai.,Zhou，Qing.,Xu，Wangping.,Wen，Long.,Li，Jun.,...&Liu，Weishu.(2022).Anion Size Effect of Ionic Liquids in Tuning the Thermoelectric and Mechanical Properties of PEDOT:PSS Films through a Counterion Exchange Strategy.ACS applied materials & interfaces,14(24),27911-27921.

Li，Qikai,et al."Anion Size Effect of Ionic Liquids in Tuning the Thermoelectric and Mechanical Properties of PEDOT:PSS Films through a Counterion Exchange Strategy".ACS applied materials & interfaces 14.24(2022):27911-27921.