Fabrication and characterization of flexible graphene films with kirigami-inspired structural configurations

Herein, we represent a study where kirigami techniques were utilized to construct flexible or articulated structures of graphene films that resemble the way the muscles or body parts of worms or caterpillars move. Graphene was fabricated by laser-induced graphene (LIG) as it offers potential benefits in terms of scalability and manufacturing efficiency. The characterization of LIG was carried out by scanning electron microscopy (SEM), energy-dispersive X-ray spectroscopy (EDX), Raman spectroscopy, and X-ray photoelectron spectroscopy (XPS) to analyze its chemical structure, composition, and defect properties. Mechanical tests were then conducted on various kirigami-inspired designs, including a novel design developed for this study to evaluate their mechanical and electrical performance. The design was then subjected to electrical performance evaluation in two different device configurations to determine the potential and applicability of these designs in stretchable electronic applications. Compared to other designs, the arrow-shaped novel kirigami pattern demonstrated excellent mechanical performance which implied that the unique biomimetic kirigami design could be suitable for device manufacturing. The design reached up to 100% elongation before break, which is the maximum value following the serpentine pattern. In addition, suggestions for improving performance were discussed, demonstrating the positive effects of various geometric improvements and coatings.