Combining Electrospinning and Electrode Printing for the Fabrication of Stretchable Organic Electrochemical Transistors

Abstract

Stretchable conductors and organic electrochemical transistors (OECT) were fabricated from PEDOT:Tos (poly (3,4-ethylenedioxythiophene):iron tosylate) nanofibers. The devices were prepared by a combination of electrospinning and electrode printing followed by vapor phase polymerization (VPP). The impact of both the processing time and the composition of three electrospinning mixtures on the electrospun fiber mats was evaluated by scanning electron microscopy and cyclic voltammetry. Fibrillar mats prepared from the different mixtures maintained their electrical properties and could be stretched up to 140% of their original length. Stretchable OECTs were fabricated by printing silver drain and source electrodes directly on the conductive spun fibers. The fabricated devices showed transistor behavior up to ∼50% strain.

Enhancing the performance of transparent and highly stretchable organic electrochemical transistors by acid treatment and copolymer blending of electrospun PEDOT:PSS fibers

“…Electrospinning was done similar to previous reports, using a Linari RT collector. 41 Fibers without any visible droplets were obtained by adjusting the spinning parameters. The mixture used for electrospinning, consisting of Clevios PH1000 (77.8 wt%), DMF (4.9 wt%), and PEG–PPG–PEG (15.6 wt%) was adapted from previously reported work.…”

“…Scanning electron microscopy (SEM), sheet resistance, conductivity, stretching, and electrochemical measurements were done similar to a previous report. 41 The thickness of the spincoated films was measured with a stylus profilometer (Dek-takXT Bruker). Cyclic voltammetry was done with electrospun fibers deposited on a 25 mm 2 carbon paper with an Ag wire pseudo-reference and platinum mesh counter electrodes.…”

“…Organic Electrochemical Transistors (OECTs) were prepared according to known methods by electrospinning fibers either on glass or stretchable VHB substrates. 41 Briefly, electrospun fiber mats were plasma etched to form OECTs channels and silver electrodes were printed as both drain and source electrodes. Conductivity enhancement of the deposited PEDOT:PSS was achieved by dropcasting sulfuric acid (18 M) on top of the fiber mats and allowing it to react for 1 minute.…”

“…We recently demonstrated that the conductivity and the stretchability of fiber mats prepared from electrospun PEDOT:tosylate are closely related to their morphology. 41 We highlighted the formation of fused fibers at their crossing nodes as a key factor in the electrical and mechanical properties in the resulting fiber mats. On one hand, fused fibers increased the conductivity by creating a network of fibers connected to one another.…”

Effect of Electrode Type on Electrospun Membrane Morphology Using Low-Concentration PVA Solutions

“…Therefore, innovations such as coaxial electrospinning, mixing and multiple electrospinning, core-shell electrospinning, blow-assisted electrospinning, and bubble electrospinning have been proposed [1][2][3]. Several technologies have been combined with electrospinning to produce materials, e.g., electrospinning and electrode printing [4], electrospinning and electrospraying [5], and other techniques [6]. Unlike other membrane production methods (for instance, the non-solvent-induced phase separation process and solution phase inversion method), electrospinning does not require additional solvents, the fiber diameters and porosity are relatively easy to control, and the membrane consists entirely of fibers (not only porous but also completely fibrous) with high surface area-to-volume or length-to-diameter ratios [7,8].…”