Wojnarowska Z, Musiał M, Cheng S, Drockenmuller E, Paluch M
Institute of Physics, the University of Silesia in Katowice, Silesian Center for Education and Interdisciplinary Research, 75 Pulku Piechoty 1A, 41-500 Chorzow, Poland.
Université Lyon, Université Lyon 1, CNRS, Ingénierie des Matériaux Polymères UMR 5223, F-69003 Lyon, France.
Phys Rev E. 2020 Mar;101(3-1):032606. doi: 10.1103/PhysRevE.101.032606.
Segmental dynamics is considered as a major factor governing ionic conductivity of polymerized ionic liquids (PILs), envisioned as potential electrolytes in fuel cells and batteries. Our dielectric studies performed in T-P thermodynamic space on ionene, composed of the positively charged polymer backbone and freely moving anions, indicate that other relaxation modes, completely ignored so far, can affect the charge transport in PILs as well. We found that fast mobility manifested by a secondary β process promotes segmental dynamics and thereby increases ionic conductivity making the studied material a first coupled PIL of superionic properties. The molecular mechanism underlying such a β process has been identified as Johari-Goldstein relaxation giving experimental proof that fast secondary relaxations of intermolecular origin exist also in PILs and thereby reveal a universal character.
链段动力学被认为是决定聚合离子液体（PILs）离子电导率的主要因素，聚合离子液体有望成为燃料电池和电池中的潜在电解质。我们在T-P热力学空间中对由带正电的聚合物主链和自由移动的阴离子组成的紫罗碱进行的介电研究表明，迄今为止完全被忽视的其他弛豫模式也会影响PILs中的电荷传输。我们发现，由二级β过程表现出的快速迁移率促进了链段动力学，从而提高了离子电导率，使所研究的材料成为具有超离子性质的首个耦合PIL。这种β过程背后的分子机制已被确定为乔哈里-戈尔茨坦弛豫，实验证明PILs中也存在分子间起源的快速二级弛豫，从而揭示了其普遍性。
