Graphene-based Laser Propulsion for Space Application

Space exploration is a pivotal endeavor that expands human knowledge and unlocks new possibilities[1]. Presently, there are thousands of satellites in orbit that serve as the foundation of Earth's communication system [2]. Space propulsion technologies can be categorized into three types [3]. First, escape propulsion[4], for leaving Earth's surface and reaching orbit, and second, in-space propulsion[2], for maneuvering in orbit. Last is the deep space propulsion[5], for traveling from orbit to outer space. While the technologies used in current launch vehicles for escape propulsion are well-established, there are promising prospects for significant technological advancements in the in-space and deep-space vehicles [6]. Over the years, multiple propulsion systems have been developed, each with its own advantages and disadvantages [7]. As the demand for space exploration rises, the development of new and efficient propulsion systems is essential to advancing our space capabilities [8]. In-space propulsion systems face several challenges, including orbital decay[9], fuel efficiency[10], manoeuvrability[11], and long- duration operations [12]. Photonic propulsion is considered as the key to overcome the limitations of conventional rocketry-based propulsion technologies and potentially paving the way into a new era in space [13]. Due to their numerous advantages such as resilience to electromagnetic interference, efficiency, and low power consumption, their use has also significantly grown in space applications [14], [15]. Recently, there has been a lot of interest in the interactions between laser beams and Graphene Based Materials (GBM) [16], [17]. Three dimensional (3D) connected graphene structures are of particular interest for laser propulsion [18], [19]. The graphene sponge is a porous 3D connected material of graphene sheets with low density (1-100 g/cm³) [16], [17]. Graphene-based sponges exhibit good electrical conductivity (up to 10 S/cm), adjustable porosity, ultralow density reaching 0.16 mg cm³, excellent mechanical performances; it has values of Young's modulus up to10 MPa [13], [20], [21]._Our study investigates the propulsion force of graphene sponges made of concentrations 1g/l to 5 g/l when exposed to continuous wave infrared lasers of wavelength 422 nm under rarified vacuum level (10 000 Pa) and high34 vacuum level (below 30 Pa). The sponge samples are characterized using Scnanning Electron Microscopy (SEM). To the best of our knowledge, this is the first-time sponges made out of pure graphene are being studied for laser propulsion system.