Laser-induced graphene (LIG) has emerged as a promising carbon nanomaterial platform owing to its scalability and tunable surface properties. Although its electrical and structural characteristics have been widely explored, the precise modulation of the surface energy remains challenging, particularly in ultrathin configurations. In this study, we investigated the wetting behavior of an ultrathin LIG synthesized from a fluorinated polyimide (F-PI) thin-film precursor using ultraviolet (UV) laser irradiation. Systematic variations in laser exposure induced morphologic transitions from hierarchical porous networks to compact planar structures, accompanied by changes in the chemical composition, including fluorine depletion and oxygen incorporation. These combined effects result in a broad range of wetting behaviors, including superhydrophobicity and hydrophilicity. Remarkably, LIG produced under single irradiation exhibited a rose-petal-like wetting state characterized by a high contact angle and strong droplet adhesion, a phenomenon not previously reported in LIG systems. This work elucidates the interplay between laser-induced nanostructuring and surface chemistry in governing wetting behavior and establishes a controllable strategy for fabricating functional carbon surfaces for applications in microfluidics, selective adhesion, and water-repellent coating technologies.

Rose petal wetting behavior realized by ultrathin laser-induced graphene
    Abstract
    1 Introduction
    2 Materials and methods
        2.1 Synthesis of ultrathin F-LIG
        2.2 Characterization
    3 Results and discussion
    4 Conclusions
    Acknowledgements 
    References

• Hee Ra Lee(School of Materials Science and Engineering, Pusan National University, Busan 46241, Republic of Korea)
• Hong Gun Kim(School of Materials Science and Engineering, Pusan National University, Busan 46241, Republic of Korea)
• Seoung‑Ki Lee(School of Materials Science and Engineering, Pusan National University, Busan 46241, Republic of Korea) Corresponding author
• Tae‑Wook Kim(Department of Flexible and Printable Electronics, Jeonbuk National University, Jeonju 54896, Republic of Korea, Department of JBNU‑KIST Industry‑Academia Convergence Research, Jeonbuk National University, Jeonju 54896, Republic of Korea)
• Sukang Bae(Department of JBNU‑KIST Industry‑Academia Convergence Research, Jeonbuk National University, Jeonju 54896, Republic of Korea, Institute of Advanced Composite Materials, Korea Institute of Science and Technology (KIST), 92 Chudong‑Ro, Bongdong‑Eup, Wanju 55324, Republic of Korea)
• Jong‑Seong Bae(Yeongnam Regional Center, Korea Basic Science Institute, Busan 46742, Korea)
• Ji‑won Park(R & D Center of JB Lab Corporation, Seoul 08788, Republic of Korea)