Biocompatible, Transparent, and High-Areal-Coverage Kirigami PEDOT:PSS Electrodes for Electrooculography-Derived Human–Machine Interactions

Abstract

Electronic skin sensors prepared from biocompatible and biodegradable polymeric materials significantly benefit the research and scientific community, as they can reduce the amount of effort required for e-waste management by deteriorating or dissolving into the environment without pollution. Herein, we report the use of polylactic acid (PLA)a promising plant-based bioplasticand highly transparent, conductive, biocompatible, and flexible poly­(3,4-ethylenedioxythiophene) polystyrene sulfonate (PEDOT:PSS) materials to fabricate kirigami-based stretchable on-skin electrophysiological sensors via a low-cost and rapid laser cutting technique. The sensor stack with PEDOT:PSS and PLA layers exhibited high transparency (>85%) in the wavelength range of 400–700 nm and stay attached conformally to the skin for several hours without adverse effects. The Y-shaped kirigami motifs inspired by the microcracked gold film endowed the sensor with attributes such as high areal coverage (∼85%), breathability (∼40 g m–2 h–1), and multidirectional stretchability. The sensor has been successfully applied to monitor electrophysiological signals and demonstrated with an eye movement-supported communication interface for controlling home electronic appliances.

PEDOT:PSS‐Based Bioelectronic Devices for Recording and Modulation of Electrophysiological and Biochemical Cell Signals

“…Right: flexible and stretchable PEDOT:PSS-based devices used as electronic skin, electronic textile, and complementary circuit. Reproduced with permission [31]. Copyright 2021, American Chemical Society;[32] Copyright 2017, The Royal Society of Chemistry;[33] Copyright 2019, American Association for the Advancement of Science (AAAS).…”

Kirigami‐Inspired Biodesign for Applications in Healthcare

“…Staggered linear and Y-shape cuts (15 mm and 5 mm) [60] Photoactive silk fibroin Photolithography Staggered linear cuts (25 µm), branched Y-shape cuts, saddles, chevrons [37] Graphite electrodes on polyimide sheet Laser cutting Staggered linear cuts (over 3 cm) [61] Gold nanofilms Dual-beam focused ion beam (FIB)/SEM Arcs and 3D microdomes (sub-50-nm) [27] Gold traces embedded in thin-film Parylene C Oxygen plasma etching Serpentine cuts [62] Mono-layer MoS 2 on PDMS Molding and plasma etching Linear patterns, pyramids, out-of-plane springs with alternating C-shapes [35] PMMA-PI composite Wet etching and laser cutting 2D hierarchical designs [63] PEO-PAA composite Blade cutting Curved patterns, linear cuts [64] Multiwalled boron nitride nanotubes Pressure-induced Folded nanoribbon internal structures/pleats [65] PLA-PEDOT:PSS Laser cutting Y-shape cuts [24] Hydrogel films-carboxyl-Zr 4+ metal coordination complexes Photolithography Custom papercut designs, woven-like alternating vertical/horizontal lines [30] Graphene sandwiched between polyimide sheets Photolithography and reactive ion etching Mesh (islands connected by kirigami bridges) [66] Liquid crystal elastomer Two-photon polymerization (2PP) Linear cuts, hinged squares, [67] PET encapsulated in PDMS Laser cutting Graded kirigami (10 mm segments of increasing void area) [68] PVDF-TrFE composite (ZnO nanoparticles and MWCNTs)…”

“…Reproduced with permission. [ 24 ] Copyright 2021, American Chemical Society. Flexibility as seen in a wearable transparent kirigami heater that operates on the wrist and performs under dynamic movements.…”

“…The device is similar to that shown in Figure1. Reproduced with permission [24]. Copyright 2021, American Chemical Society.…”

High-Adhesive Flexible Electrodes and Their Manufacture: A Review

“…As a method for measuring electrical signals, electrodes are the most critical technology in the EP working system. EP signal recording applications include the brain-computer interface, human-computer interface (HCI) [2][3][4], and human-machine interface (HMI) [5], etc., in addition to some innovative applications, such as attention detection [6] and the development of a point-of-care (POC) [7] diagnostic platform.…”