npj Flexible Electronics (Mar 2024)

Deformable micro-supercapacitor fabricated via laser ablation patterning of Graphene/liquid metal

  • Keon-Woo Kim,
  • Seong Ju Park,
  • Su-Jeong Park,
  • Inae Kim,
  • Bomi Park,
  • Se Hyun Kim,
  • Unyong Jeong,
  • Jin Kon Kim,
  • Chanwoo Yang

DOI
https://doi.org/10.1038/s41528-024-00306-2
Journal volume & issue
Vol. 8, no. 1
pp. 1 – 9

Abstract

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Abstract Deformable and miniaturized energy storage devices are essential for powering soft electronics. Herein, we fabricate deformable micro supercapacitors (MSCs) based on eutectic gallium-indium liquid metal (EGaIn) current collectors with integrated graphene. The well-define interdigitated electrode patterning with controlled gap is successfully realized by using the laser ablation because of a strong laser absorption of graphene and EGaIn. By judicious control of gap size between neighboring interdigitated electrodes and mass loading of graphene, we achieve a high areal capacitance (1336 µF cm−2) with reliable rate performance. In addition, owing to the intrinsic liquid characteristics of EGaIn current collector, the areal capacitance of fabricated MSC retains 90% of original value even after repetitive folding and 20% stretching up to 1000 cycles. Finally, we successfully integrate deformable MSC with a commercial light-emitting diode to demonstrate the feasibility of MSC as a deformable power source. The fabricated MSCs operate stably under various mechanical deformations, including stretching, folding, twisting, and wrinkling.