Pressure-driven laser induced graphene: transient pressure-enhanced structural ordering via femtosecond laser irradiation

Abstract

The current laser-induced graphene (LIG) methods, including photothermal and photochemical approaches, are promising for flexible electronics, yet face distinct limitations. The photothermal approach often produces graphene with uncontrolled structural and functional properties, while the photochemical approach is restricted to a narrow range of precursors. To address these limitations, we propose a pressure-driven LIG (P-LIG) method that uses transient laser-generated pressure fields as an additional control parameter to improve graphene quality. An integrated framework combining ultrafast pump–probe interferometric imaging, large-scale molecular dynamics (MD) simulations, and explainable artificial intelligence (XAI) was developed to investigate this approach. Time-resolved measurements reveal the generation of transient pressure fields during femtosecond laser irradiation of polyimide films, confirming pressure as an intrinsic feature of the process. MD simulations under controlled pressure conditions demonstrate that pressure promotes the nucleation and stacking of graphene layers, resulting in more continuous and planar graphitic networks. XAI analysis quantitatively identifies the important contributions of pressure. These results confirm that the transient pressure introduced by the P-LIG method plays a key role in promoting more ordered, continuous, and planar graphene networks, and enhancing structural integrity and material quality beyond traditional methods. This provides a practical pathway for improving the performance and reliability of LIG-based flexible electronic devices.