Ablation threshold, structural modification, and sensing of graphene oxide thin film induced by UV nanosecond laser

Reduction of graphene oxide by laser irradiation is crucial for developing conductive thin films. This study investigates the ablation threshold, reduction of graphene oxide, and high-precision patterning by UV nanosecond laser irradiation of graphene oxide films on flexible substrates. The ablation threshold of graphene oxide thin film was evaluated by examining the relationship between micropore diameters and laser pulse energy density. The single pulse ablation threshold was 2.29 J/cm², indicating that the UV nanosecond laser energy density is sufficient for the ablation of graphene oxide. Based on ablation threshold evaluation, graphene oxide was reduced by UV nanosecond laser irradiation, and laser-irradiated graphene oxide-based flexible thin film with four different line widths was fabricated. UV nanosecond laser irradiation graphene oxide-based grid structure patterns on the flexible substrates were fabricated by analyzing these different line widths. In addition, laser-irradiated graphene oxide-based grid structure flexible electrode were used to monitor human hand motion and finger press sensing. This study underscores the significance of laser irradiation of graphene oxide, a controllable strategy, and highlights the novelty and practical applications for fabricating flexible graphene oxide-based electronics.