Graphene-Enhanced Wood: A Lightweight and Sustainable Material for Spacecraft Structures

Laser ablation debris removal is a promising means of achieving sustainable space operations [1,2]. However, conventional metals in spacecraft ablate into spallation particles [3] that may harden and impact spacecraft or oxidize and deplete the ozone layer [4,5]. Wood is a candidate space structural material since it is 84% less dense than conventional metals such as Aluminium alloys and does not produce polluting spallation particles such as alumina (Al₂O₃) [3,6,7]. Another candidate material is Graphene, which maintains an electric conductivity of 350,000 cm²/V s [8], mechanical stiffness of 1 TPa [9], and EMI shielding efficiency of 90 dB [10] in space conditions [6].<br/>This study proposes graphene-enhanced wood as a novel space material harnessing both those materials’ properties, made through the procedure illustrated in Fig. 1. Delignification creates micropores that enhance flexibility and formability [11]. Graphene, produced through microwave-assisted exfoliation of thermally expanded graphite obtained from treating graphite flakes with perchloric acid [12], is then infused into the wood, coating inner cell walls and pores [13]. Finally, densification through air-drying or oven-drying at 60 °C for 12 hrs, or hot-pressing under 4 MPa pressure for 12 hrs at 80 °C, produces the final rigid form [11,14,15].<br/>Our initial results demonstrate significant enhancement of the wood's tensile strength (up to six times), electrical conductivity (up to 35 S/m), EMI shielding efficiency (up to 16 dB), and laser ablation performance. Through an ongoing optimization process, these parameters will be further improved, and the final results will be presented in the final manuscript.