Processing optimization of PEDOT:PSS and PEDOT:PSS/Tween 80 films

• Published in: Polymer journal Vol. 55; no. 3; pp. 253 - 260
• Main Authors: Carter, Joseph L., Kelly, Catherine A., Jenkins, Mike J.
• Format: Journal Article
• Language: English
• Published: London Nature Publishing Group UK 01.03.2023; Nature Publishing Group
• Subjects: 639/301/923/1028; 639/624/399/1028; Annealing; Biomaterials; Bioorganic Chemistry; Chemistry; Chemistry and Materials Science; Chemistry/Food Science; Electrical resistivity; Moisture effects; Moisture removal; Optimization; Original Article; Polymer Sciences; Surfaces and Interfaces; Thermal stability; Thin Films
• ISSN: 0032-3896; 1349-0540
• DOI: 10.1038/s41428-022-00740-x

The optimum processing conditions for PEDOT:PSS and PEDOT:PSS/Tween 80 cast films were investigated by considering film quality and resistivity. The thermal stabilities of these materials were found to strongly influence the accessible annealing temperatures, especially in the presence of the conductivity-enhancing agent Tween 80. The resistivities of PEDOT:PSS films with and without Tween 80 decreased by up to 85% with increases in both annealing temperature and time until a plateau was reached. In addition, thermal structural rearrangements of these polymers were the key driving factors that reduced resistivity, with water removal alone insufficient. Finally, the optimum processing conditions for PEDOT:PSS and PEDOT:PSS/Tween 80 films are detailed. The optimum processing conditions for PEDOT:PSS and PEDOT:PSS/Tween 80 cast films were determined in terms of sheet resistivity and film quality. The sheet resistivity of the films was found to decrease by up 85% following annealing at 140 °C. Further analysis showed this reduction to be created by both moisture removal and structural rearrangement. The presence of Tween 80 significantly altered the thermal stability of PEDOT:PSS films highlighting the importance of reoptimizing processing conditions for each additive used.