Stretchable Self-Healing Polymeric Dielectrics Cross-Linked Through Metal-Ligand Coordination.
A self-healing dielectric elastomer is achieved by the incorporation of metal-ligand coordination as cross-linking sites in nonpolar polydimethylsiloxane (PDMS) polymers. The ligand is 2,2'-bipyridine-5,5'-dicarboxylic amide, while the metal salts investigated here are Fe(2+) and Zn(2+) with various counteranions. The kinetically labile coordination between Zn(2+) and bipyridine endows the polymer fast self-healing ability at ambient condition. When integrated into organic field-effect transistors (OFETs) as gate dielectrics, transistors with FeCl2 and ZnCl2 salts cross-linked PDMS exhibited increased dielectric constants compared to PDMS and demonstrated hysteresis-free transfer characteristics, owing to the low ion conductivity in PDMS and the strong columbic interaction between metal cations and the small Cl(-) anions which can prevent mobile anions drifting under gate bias. Fully stretchable transistors with FeCl2-PDMS dielectrics were fabricated and exhibited ideal transfer characteristics. The gate leakage current remained low even after 1000 cycles at 100% strain. The mechanical robustness and stable electrical performance proved its suitability for applications in stretchable electronics. On the other hand, transistors with gate dielectrics containing large-sized anions (BF4(-), ClO4(-), CF3SO3(-)) displayed prominent hysteresis due to mobile anions drifting under gate bias voltage. This work provides insights on future design of self-healing stretchable dielectric materials based on metal-ligand cross-linked polymers.
Ying-Li
YL
Rao
Alex
A
Chortos
Raphael
R
Pfattner
Franziska
F
Lissel
Yu-Cheng
YC
Chiu
Vivian
V
Feig
Jie
J
Xu
Tadanori
T
Kurosawa
Xiaodan
X
Gu
Chao
C
Wang
Corning Incorporated , SP-FR-06-1, Corning, New York 14831, United States.
Mingqian
M
He
Samsung Advanced Institute of Technology Yeongtong-gu, Suwon-si, Gyeonggi-do 443-803, South Korea.
Jong Won
JW
Chung
Zhenan
Z
Bao
D015082:2,2'-Dipyridyl; D002712:Chlorides / Q000737:chemistry; D003432:Cross-Linking Reagents; D004129:Dimethylpolysiloxanes / Q000737:chemistry; D004548:Elasticity; D004581:Electronics; D005296:Ferrous Compounds / Q000737:chemistry; D008024:Ligands; D008670:Metals / Q000737:chemistry*; D011108:Polymers / Q000737:chemistry*; D017967:Zinc Compounds / Q000737:chemistry
D002712:Chlorides; D003432:Cross-Linking Reagents; D004129:Dimethylpolysiloxanes; D005296:Ferrous Compounds; D008024:Ligands; D008670:Metals; D011108:Polymers; D017967:Zinc Compounds; D015082:2,2'-Dipyridyl; C013830:baysilon; C016837:zinc chloride; C029451:ferrous chloride