Effect of Alkyl Side Chain Length on Electrical Performance of Ion-Gel-Gated OFETs Based on Difluorobenzothiadiazole-Based D-A Copolymers

Overview

Journal Polymers (Basel)

Publisher MDPI

Date 2024 Dec 17

PMID 39684034

Authors

Han Zhou

Zaitian Cheng

Guoxing Pan

Lin Hu

Fapei Zhang

Affiliations

Soon will be listed here.

Abstract

The performance of organic field-effect transistors (OFETs) is highly dependent on the dielectric-semiconductor interface, especially in ion-gel-gated OFETs, where a significantly high carrier density is induced at the interface at a low gate voltage. This study investigates how altering the alkyl side chain length of donor-acceptor (D-A) copolymers impacts the electrical performance of ion-gel-gated OFETs. Two difluorobenzothiadiazole-based D-A copolymers, PffBT4T-2OD and PffBT4T-2DT, are compared, where the latter features longer alkyl side chains. Although PffBT4T-2DT shows a 2.4-fold enhancement of charge mobility in the SiO-gated OFETs compared to its counterpart due to higher crystallinity in the film, PffBT4T-2OD outperforms PffBT4T-2DT in the ion-gel-gated OFETs, manifested by an extraordinarily high mobility of 17.7 cm/V s. The smoother surface morphology, as well as stronger interfacial interaction between the ion-gel dielectric and PffBT4T-2OD, enhances interfacial charge accumulation, which leads to higher mobility. Furthermore, PffBT4T-2OD is blended with a polymeric elastomer SEBS to achieve ion-gel-gated flexible OFETs. The blend devices exhibit high mobility of 8.6 cm/V s and high stretchability, retaining 45% of initial mobility under 100% tensile strain. This study demonstrates the importance of optimizing the chain structure of polymer semiconductors and the semiconductor-dielectric interface to develop low-voltage and high-performance flexible OFETs for wearable electronics applications.

References

Sekiguchi A, Tanaka F, Saito T, Kuwahara Y, Sakurai S, Futaba D . Robust and Soft Elastomeric Electronics Tolerant to Our Daily Lives. Nano Lett. 2015; 15(9):5716-23. DOI: 10.1021/acs.nanolett.5b01458. View

Wang P, Zakeeruddin S, Exnar I, Gratzel M . High efficiency dye-sensitized nanocrystalline solar cells based on ionic liquid polymer gel electrolyte. Chem Commun (Camb). 2003; (24):2972-3. DOI: 10.1039/b209322g. View

Xu H, Zhu Q, Lv Y, Deng K, Deng Y, Li Q . Flexible and Highly Photosensitive Electrolyte-Gated Organic Transistors with Ionogel/Silver Nanowire Membranes. ACS Appl Mater Interfaces. 2017; 9(21):18134-18141. DOI: 10.1021/acsami.7b04470. View

Lee K, Kang M, Zhang S, Gu Y, Lodge T, Frisbie C . "Cut and stick" rubbery ion gels as high capacitance gate dielectrics. Adv Mater. 2012; 24(32):4457-62. DOI: 10.1002/adma.201200950. View

Xu J, Wu H, Zhu C, Ehrlich A, Shaw L, Nikolka M . Multi-scale ordering in highly stretchable polymer semiconducting films. Nat Mater. 2019; 18(6):594-601. DOI: 10.1038/s41563-019-0340-5. View

Hui Z, Zhang L, Ren G, Sun G, Yu H, Huang W . Green Flexible Electronics: Natural Materials, Fabrication, and Applications. Adv Mater. 2023; 35(28):e2211202. DOI: 10.1002/adma.202211202. View

Huang W, Chen J, Yao Y, Zheng D, Ji X, Feng L . Vertical organic electrochemical transistors for complementary circuits. Nature. 2023; 613(7944):496-502. PMC: 9849123. DOI: 10.1038/s41586-022-05592-2. View

Ye H, Ryu K, Kwon H, Lee H, Wang R, Hong J . Amorphous Fluorinated Acrylate Polymer Dielectrics for Flexible Transistors and Logic Gates with High Operational Stability. ACS Appl Mater Interfaces. 2023; 15(27):32610-32620. DOI: 10.1021/acsami.3c02010. View

Campana A, Cramer T, Simon D, Berggren M, Biscarini F . Electrocardiographic recording with conformable organic electrochemical transistor fabricated on resorbable bioscaffold. Adv Mater. 2014; 26(23):3874-8. DOI: 10.1002/adma.201400263. View

10.

Bischak C, Flagg L, Ginger D . Ion Exchange Gels Allow Organic Electrochemical Transistor Operation with Hydrophobic Polymers in Aqueous Solution. Adv Mater. 2020; 32(32):e2002610. DOI: 10.1002/adma.202002610. View

11.

Liu H, Liu D, Yang J, Gao H, Wu Y . Flexible Electronics Based on Organic Semiconductors: from Patterned Assembly to Integrated Applications. Small. 2023; 19(11):e2206938. DOI: 10.1002/smll.202206938. View

12.

Oh J, Rondeau-Gagne S, Chiu Y, Chortos A, Lissel F, Wang G . Intrinsically stretchable and healable semiconducting polymer for organic transistors. Nature. 2016; 539(7629):411-415. DOI: 10.1038/nature20102. View

13.

Kim S, Hong K, Xie W, Lee K, Zhang S, Lodge T . Electrolyte-gated transistors for organic and printed electronics. Adv Mater. 2012; 25(13):1822-46. DOI: 10.1002/adma.201202790. View

14.

Liu Y, Zhao J, Li Z, Mu C, Ma W, Hu H . Aggregation and morphology control enables multiple cases of high-efficiency polymer solar cells. Nat Commun. 2014; 5:5293. PMC: 4242436. DOI: 10.1038/ncomms6293. View

15.

Baruah R, Yoo H, Lee E . Interconnection Technologies for Flexible Electronics: Materials, Fabrications, and Applications. Micromachines (Basel). 2023; 14(6). PMC: 10305052. DOI: 10.3390/mi14061131. View

16.

Nketia-Yawson B, Jung A, Nguyen H, Lee K, Kim B, Noh Y . Difluorobenzothiadiazole and Selenophene-Based Conjugated Polymer Demonstrating an Effective Hole Mobility Exceeding 5 cm V s with Solid-State Electrolyte Dielectric. ACS Appl Mater Interfaces. 2018; 10(38):32492-32500. DOI: 10.1021/acsami.8b14176. View

17.

Qin R, Wu Y, Ding Z, Zhang R, Yu J, Huang W . Highly Stretchable Conjugated Polymer/Elastomer Blend Films with Sandwich Structure. Macromol Rapid Commun. 2023; 45(1):e2300240. DOI: 10.1002/marc.202300240. View

18.

Han S, Peng H, Sun Q, Venkatesh S, Chung K, Lau S . An Overview of the Development of Flexible Sensors. Adv Mater. 2017; 29(33). DOI: 10.1002/adma.201700375. View

19.

Kim H, Sim K, Thukral A, Yu C . Rubbery electronics and sensors from intrinsically stretchable elastomeric composites of semiconductors and conductors. Sci Adv. 2017; 3(9):e1701114. PMC: 5590788. DOI: 10.1126/sciadv.1701114. View

20.

Zheng Y, Michalek L, Liu Q, Wu Y, Kim H, Sayavong P . Environmentally stable and stretchable polymer electronics enabled by surface-tethered nanostructured molecular-level protection. Nat Nanotechnol. 2023; 18(10):1175-1184. DOI: 10.1038/s41565-023-01418-y. View