Molecular dynamics simulation and experimental analysis of laser-induced graphene on moso bamboo

Abstract

Laser-induced technology is an efficient and eco-friendly method for graphene preparation, enabling in situ generation of graphene through laser irradiation of carbon-containing precursors. The formation process of laser-induced graphene (LIG) using moso bamboo as the precursor was systematically investigated through a combined approach of molecular dynamics simulations and experimental characterization. For simulations, an innovative simplified moso bamboo model comprising three primary components (cellulose, hemicellulose, and lignin) was constructed by the Materials Studio software. The LIG formation process was simulated at the atomic scale using LAMMPS software with the ReaxFF reactive force field to elucidate the underlying mechanism. During experiments, the multiple characterization techniques were employed to analyze the microstructure, elemental composition, structural features, crystalline phases and defect structure of the LIG. The simulation results indicated that the formation of bamboo-derived LIG follows a pyrolysis-dominated mechanism, achieving a graphene yield of 35.29%. The process generated defective carbon networks dominated by hexagonal rings (53.65%), with concomitant release of small gas molecules, including H₂ (50.20%), CO (39.87%), H₂O (5.94%), and CO₂ (3.99%). The characterization results from Raman, TEM, XPS, and XRD confirm that laser irradiation successfully converted biomass moso bamboo into a carbon-based material dominated by sp² hybridization, exhibiting a defective multilayer graphene structure. In addition, SEM and EDS observations reveal the microporous structure of LIG and changes in elemental composition before and after processing, which align with the simulation results, validating the rationality of the constructed simplified model. By revealing the synergistic pyrolysis-graphitization mechanism of moso bamboo, this study validates the applicability of the multicomponent simplified model to real biomass systems, enabling controllable preparation of biomass-derived graphene and enhanced resource utilization of moso bamboo.