Micrometer‐Thin Nanocellulose Foils for 3D Organic Electronics

Cellulose is a natural polymer with great properties such as high optical transparency and mechanical strength, flexibility, and biodegradability. Hence, cellulose-based foils are suitable for the replacement of synthetic polymers as substrate materials in organic electronics. This article reports the fabrication of ultrathin, free-standing cellulose foils by spraying aqueous 2,2,6,6-tetramethylpiperidine-1-oxyl-nanocellulose (TEMPO) fibrils ink layer-by-layer on a hot substrate using a movable spray nozzle. The resulting foils are only 2 +/- 1 mu m in thickness with an average basis weight of 1.9 g m-2, which ranges in the same scale as the world's thinnest paper. The suitability of these ultra-thin nanocellulose foils as a sustainable substrate material for organic electronic applications is demonstrated by testing the foils resistance against organic solvents. Furthermore, silver nanowires (AgNWs) and the blend poly(3,4-ethylenedioxythiophene):polystyrene sulfonate (PEDOT:PSS) are integrated into the foils, and the foils are molded into 3D paper structures in order to create conductive, paper-based building blocks for organic electronics. This article reports the fabrication of free-standing cellulose foils via layer-by-layer spray deposition. The foils are 2 mu m thin with an average basis weight of 1.9 g m-2, which ranges in the same scale as the world's thinnest paper. By integrating conductive nanoparticles and polymers, these foils become 3D, lightweight, functional components of individual shapes, suitable for organic electronics. image