Stretchable Self-Healing Polymeric Dielectrics Cross-Linked Through Metal-Ligand Coordination
Stretchable Self-Healing Polymeric Dielectrics Cross-Linked Through Metal-Ligand Coordination
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DOI：
10.1021/jacs.6b02428
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发表时间：
2016-05-11
影响因子：
15
通讯作者：
Bao, Zhenan
中科院分区：
文献类型：
--
作者：
Rao, Ying-Li;Chortos, Alex;Bao, Zhenan
通过在非极性聚二甲基硅氧烷(PDMS)聚合物中引入金属-配体配位作为交联点，获得了一种自愈介电弹性体。配体是2，2‘-联吡啶-5，5’-二羧胺，而这里研究的金属盐是带有各种反阴离子的Fe2+和Zn2+。锌离子与联吡啶之间动力学不稳定的配位作用赋予了聚合物在常温下快速自愈的能力。当作为栅电介质集成到有机场效应晶体管(OFET)中时，与PDMS相比，具有FeCl2和ZnCl2盐交联型PDMS的晶体管表现出比PDMS更高的介电常数，并且表现出无滞后转移特性，这是由于PDMS中的低离子电导率以及金属阳离子和小的Cl-离子之间的强烈的柱状相互作用，可以防止移动阴离子在栅偏压下漂移。制备了具有FeCl2-PDMS介质的全可伸缩晶体管，并表现出理想的传输特性。即使在100%应变下循环1000次后，栅漏电流仍然很低。机械稳定性和稳定的电气性能证明了其在可伸缩电子设备中的应用。另一方面，栅电介质中含有大尺寸阴离子(BF4-、ClO4-、CF3SO3-)的晶体管由于在栅偏压下移动的阴离子漂移而表现出明显的滞后。这项工作为未来基于金属配体交联聚合物的自愈性可伸展介电材料的设计提供了见解。
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 Fe2+ and Zn2+ with various counteranions. The kinetically labile: coordination-between Zn2+ 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.