Polymer electrolyte based on DNA and N,N,N-trimethyl-N-(2-hydroxyethyl)ammonium bis(trifluoromethylsulfonyl)imide

•A new polymer electrolyte is reported based on DNA and cholinium IL.•Thermal stability up to 155 °C and a wide electrochemical window of ≈3.5 V.•Thermal and electrochemical stabilities of the electrolytes are adequate for application on devices.

Combining ionic liquids (ILs) with polymers offers the prospect of new applications, where they surpass the performance of conventional media, such as organic solvents, giving advantages in terms of improved safety and a higher operating temperature range. In this work we have investigated the morphology, thermal and electrochemical properties of polymer electrolytes prepared through the addition of controlled quantities of the cholinium-based IL N,N,N-trimethyl-N-(2-hydroxyethyl)ammonium bis(trifluoromethylsulfonyl)imide ([N1 1 1 2(OH)] [NTf2]) to a deoxyribonucleic acid (DNA) host network. These novel IL-based electrolytes have been analyzed aiming at applications in electrochemical devices. An optimized sample showed good thermal stability up to 155 °C and a wide electrochemical window of ≈3.5 V. The highest conductivity was registered for the DNA[N1 1 1 2(OH)] [NTf2] (1:1) (2.82 × 10−5 and 1.09 × 10−3 S cm−1 at 30 and 100 °C, respectively).