Graphene and Related Materials Inks and Composites for Space Applications
Recent advancements in reusable rockets have led to a precipitous drop in pay-load to orbit costs (from $55,000/kg to $2,700/kg), enabling the establishment and meteoric rise of a commercial space industry. This opening up of space has spurred the generation of novel ideas and technologies, creating an ecosystem of new companies across the globe poised to play a part in the new space economy by enabling space research, tourism, manufacturing, and interplanetary travel. Underpinning this new era is the targeted development of advanced materials and processes that enhance in-space manufacturing capability, enable in-situ resource utilization, improved spacecraft capability, and protect biological life. The need for these advanced materials is driven by the inadequate susceptibility of current materials and technologies to the harsh space and planetary environments. Effects like extreme temperature (+180 to -180 °), altered gravity (hyper- and micro-gravity), thermal cycling (16 day/night cycles every 24 hours in low Earth orbit), ultra-high vacuum, solar radiation (1380 W/cm2 at Earth radius), atomic oxygen, and galactic cosmic radiation, in addition to planetary specific environmental factors, like regolith, present complex challenges for material performance in space.
Graphene and related materials (GRMs) exhibit a range of unique properties that are size and thickness dependent, making them a versatile material platform. Their expansive range of properties and atomic composition make them attractive for advanced material solutions in space, including application in thermal control systems, radiation shielding, abrasion resistance for planetary surface exploration, electro-static charge dissipation, and light-weight, multifunctional composites, amongst others. Despite this, GRMs have yet to be used in space, while ground-based investigation of their usefulness in space applications is limited.
In this dissertation, I showcase how graphene and related materials (GRMs) can be fine-tuned via exfoliation and tailored processing conditions to enable the development of advanced materials and manufacturing capabilities for space applications. Utilizing high-pressure homogenization (HPH), I establish a framework for several techniques that enhance the effective use of GRMs, expanding the utility of HPH beyond mere exfoliation to encompass multimaterial and multiphase processing of GRMs and other nanomaterials. The ensuing chapters delve into the practical applications of the resulting GRM inks and composites across a spectrum of space technologies, spanning thermal control devices, additive manufacturing materials, and lunar surface exploration. Moreover, this work highlights the potential of in-space manufacturing (ISM) and in-situ resource utilization (ISRU) as promising avenues for advancing the use and capability of GRMs in space. Through a thorough investigation into the production, characterization, and application of GRMs, this dissertation lays a robust foundation for their future in space.