Mechanically flexible multi-stacked ITO/PEDOT:PSS hybrid superlattice films for transparent conductive electrodes

To improve the flexibility of transparent conductive electrodes (TCEs), we designed multi-stacked ITO/PEDOT:PSS hybrid superlattice (IxPy) films for flexible polymer-dispersed liquid crystal (PDLC), foldable thin-film heaters (TFHs), and flexible perovskite solar cells (PSCs). The electrical and optical properties of the multi-stacked IxPy films were examined and then optimized at the I6P5 film (ITO: 6 layers and PEDOT: 5 layers). The I6P5 film showed a sheet resistance of 149.66 Ohm/square, high transmittance of 93.75% at the visible range of (400-800) nm, and achieved the highest figure-of-merit (FOM) value of 3.50 x 10(-3), compared with the other stacked conditions. Furthermore, the I6P5 films showed better flexibility by suppressing the brittle nature of ITO through inserting very thin PEDOT:PSS. The I6P5 film as an electrode was employed as a flexible PDLC, flexible TFHs, and flexible PSCs. The I6P5-based PDLC showed a clear distinction between on-state and off-state. At the applied voltage of 60 V, the transmittance of PDLC increased to 48.829% because of the arrangement of liquid crystals in the current direction. The flexible TFHs with I6P5 superlattice electrode showed high saturation temperature of above 100 degrees C at 14 V. Moreover, the I6P5 electrodes showed similar efficiency to reference ITO films in flexible PSCs. These results indicate that the multi-stacked IxPy hybrid superlattice films offer superior potential as highly transparent and foldable or flexible conductive electrodes. (C) 2022 Elsevier B.V. All rights reserved.

Automated summary

To improve the flexibility of transparent conductive electrodes (TCEs), multi-stacked ITO/PEDOT:PSS hybrid superlattice (IxPy) films were designed and applied in flexible polymer-dispersed liquid crystal (PDLC), foldable thin-film heaters (TFHs), and flexible perovskite solar cells (PSCs). The optimized I6P5 film showed excellent electrical and optical properties, and the I6P5-based PDLC, TFHs, and PSCs demonstrated promising performance.