Stretchable and Flexible Snake Skin Patterned Electrodes for Wearable Electronics Inspired by Kirigami Structure

Abstract

Herein, snake‐skin‐patterned electrodes, with high versatility and excellent biocompatibility, are developed by combining the Kirigami structure and biomimicry. The snake‐skin electrode has excellent stretchability owing to the integration of the Kirigami structure and patterning. The snake skin patterns are optimized through finite element analysis (FEA) simulations to determine the most stretchable pattern structure. Based on the FEA results, we fabricated the optimal pattern on a polyurethane (PU) substrate by sputtering the AgPdCu alloy target. Even at high strains of 30% and 50%, the electrode exhibits much better stretchability compared with the electrode without the snake skin pattern. The best stretchable electrode exhibits a resistance change (ΔR) of less than 1.5 when it is severely stretched at up to 50% strain. Additionally, the dynamic stretching fatigue test, reveals that it exhibits stable conductivity, thus proving the effectiveness of using snake‐skin pattern for stretchable electrodes. The bending, rolling, folding and twisting tests confirm that the electrode has outstanding flexibility, too. A wearable temperature sensor with a snake‐skin‐patterned electrode exhibits stable and highly sensitive temperature sensing properties. In addition, light emitting diodes connected to the stretchable electrode exhibits stable brightness despite severe deformation of the electrodes.

Recent advances in the construction and application of stretchable PEDOT smart electronic membranes

“…37 In-plane patterned structures include serpentine, mesh, and wavy structures, 149 while out-of-plane patterned structures include kirigami, origami, honeycomb, and microporous structures. 150 By forming micron or even nano-patterned structures, the surface morphology, optical properties, and mechanical properties can be adjusted, and rigid materials can be endowed with stretchability. 151,152…”

Research Progress in Stretchable Circuits: Materials, Methods, and Applications

“…The layout of the snakeskin structure enables compression along the strain direction ensuring that the resistance of the structure does not change during stretching. [71] This method is ideal for the fabrication of temperature-sensitive materials on electrodes that can detect changes in human body temperature without being affected by strains generated by human motion.…”

Highly Stretchable and Patternable Conductive Elastomer Composites Based on Direct Cut‐Patterning Technique for Stretchable Circuit Board Applications

“…Recently, kirigami structures have been widely employed to create highly stretchable conductors. [31][32][33][34][35][36][37] Highly stretchable kirigami-structured conductive sheets fabricated by the mechanical cutting process have also been reported; [31,32] however, in these cases, the cutting process was not designed to pattern conductors into specific layouts, but was only used to form simple kirigami cuts onto target substrates. After forming the periodic cuts, the ΔR/R 0 of the ES-type composite conductor significantly decreased from ≈4.8 to ≈0.19 at 100% strain.…”