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NASA and the US Army Engineer Research and Development Center (ERDC) co-developed advanced graphene materials designed to improve the filtration rate of spacecraft water contaminants which could significantly extend the service life of existing media filtration beds. Traditional granulated activated carbon (GAC) media is characterized by having a polymodal pore structure and contains micro-, meso-, and macropores that trap and contain contaminants. By using the referenced method to add graphene nanoparticles to an existing GAC filtering substrate, additional filtering can be achieved due to graphene’s mostly mesoporous nature. A high-level overview of the graphene loading process is thus: The unloaded graphene nanoparticles are mixed with a water-based graphene suspension for an extended time at room temperature. This “graphene bath” process is repeated several times before the now graphene-loaded (up to ~ 1% by mass) filtration media is dried and prepared for packing into a filter cartridge. The graphene suspension used during the loading process may be reused multiple times, reducing consumables in the process. Laboratory testing has shown a 40x improvement in contaminant removal per mass of the absorbent (i.e., graphene) over the state of the art (granulated activated carbon) at lower loading rates, suggesting significant promise of the treated filter media posing a potential solution to the demands of an entire mission lifecycle. Potential commercial applications for this graphene loading method may lay in four distinct market segments that rely on filtration media beds (outside of aerospace): industrial filtration such as ultra-pure water refining for the semiconductor industry, commercial filtration, residential filtration, and filtration-as-a-service. Graphene nano-particles’ tunable pore sizing, in conjunction with this loading method, could offer tailored filtration boosting for existing water filter substrates. The Graphene Loading Method for Water Filtration Media has a technology readiness level (TRL) 4 (Component and/or breadboard validation in laboratory environment), and it is now available for patent licensing. Please note that NASA does not manufacture products itself for commercial sale.

NASA Ames has developed very small-sized oxygen sensors made of a graphene and titanium dioxide (TiO₂) hybrid material. With ultraviolet (UV) illumination, these sensors are capable of detecting oxygen (O₂) gas at room temperature and at ambient pressure. The sensors are able to detect oxygen at concentrations ranging from about 0.2% to about 10% by volume under 365nm UV light, and at concentrations ranging from 0.4% to 20% by volume under short wave 254nm UV light. These sensors have fast response and recovery times and can also be used to detect ozone. This unique room temperature O₂ sensor provides significant advantages in O₂ sensing applications, especially those applications where high operating temperature requirements cannot be met, or would result in inefficient manufacturing processes. Since graphene is not intrinsically responsive to O₂, and TiO₂ is not responsive to oxygen at room temperature, the materials are first synthesized as a hybrid material. The synthesized graphene- TiO₂ hybrid material is then ultrasonicated and then drop-casted onto a series of Interdigitated Electrodes (IDE) to form the sensors. Ultrasonication ensures effective charge transfer at the graphene- TiO₂ interphase. The graphene and the titanium dioxide may be present in the composite material in different ratios to ensure optimal oxygen detection. It is the combination of graphene with TiO2 that yields a semiconducting material capable of O₂ sensing at room-temperature operation.

The SABERS innovators developed novel lithium-sulfur designs, including sulfur-selenium on graphene cathodes, and lightweight bipolar plate stacking and packaging designs. SABERS is unique in several aspects, in particular, it deploys graphene-based manufacturing processes for the cathode and bipolar plates, and it uses a solid-state electrolyte in place of the liquid electrolyte found in other lithium-sulfur battery designs. The team has achieved energy densities over 500 W-hr/kg, with ongoing development targeting further improvements. Coin cell and pouch prototype demonstrations have been successful and are ongoing. Major component technologies in SABERS include the following: • S/Se Cathode – Sulfur/Selenium on graphene scaffold (LEW-20228-1) • Solid Electrolyte – Solid-state electrolyte composites (LEW-20445-1) • Bipolar Stack – Graphene plates (LAR-20257-1) Robust computational models have been developed to support the battery materials design and are available to licensees to evaluate and optimize different materials combinations and performance targets. Further developments in catholyte formulations, anode interlayering, and packaging optimization are presented in SABERS 2.0 (LEW-TOPS-188). Individual technologies can be licensed from either suite, or entire portfolios can be licensed to support solid-state battery development programs.

The interlayer consists of lithiophilic metallic or metal-containing nanoparticles supported on holey graphene, a special carbon material perforated by small holes that enables dry processing. The composite interlayer guides uniform lithium deposition and maintain stability during cycling. The result is a thin, film-like material that can be integrated (via dry processes) into battery cells as standalone interlayers or combined with solid electrolyte and cathode powders to form bi- and tri-layer structures, separating anodes and electrolytes while encouraging efficient ionic movement and long cell lifecycles. Tests found that battery cells incorporating this dry-processed interlayer achieved ultrahigh current density and low overpotential, indicating that the interlayer prevents rough patches, resists dendrite formation, and supports efficient charge and discharge over time. The interlayer has demonstrated a high lithium-ion flux (i.e., a high critical current density of ~25 mA/cm²) and has shown that full battery cells incorporating the protective layer can be successfully cycled (with an areal capacity of 7 mAh/cm²). This innovation contributes to both the SABERS (LEW-TOPS-167) and SABERS 2.0 (LEW-TOPS-188) portfolios, improving the state of the art for solid state batteries. The anode interlayer is currently at a TRL 4 and is available to license independently or as part of the larger SABERS solid-state battery suite.

Sometimes called white graphite, affordable and plentiful hBN possesses the same kind of layered molecular structure as graphite. In graphite, this structure has allowed next-generation nanomaterials like carbon nanotubes and graphene to be produced. With hBN, however, the process of converting the substance into boron nitride nanotubes (BNNT) has been too difficult to yield commercial quantities. Glenn innovators have created several new methods that could enable greater adoption of this unique nanomaterial. In the initial stage, the starter reactant is mixed with a selected set of chemicals (a metal chloride, for example) and an activation agent (such as sodium fluoride). This mixture causes hBN to become less resistant to intercalation. The intercalated product can then be exfoliated by heating the material in air, and giving the material a final rinse with a liquid-phase ferric chloride salt to dissolve any embedded impurities without damaging its internal structure. These efficiently exfoliated nanomaterials can be used to form advanced composite materials (e.g., layered with aluminum oxide to form hBN/alumina ceramic composites). Nanomaterials fabricated from hBN can also take advantage of the material's unique combination of being an electrical insulator with high thermal conductivity for applications ranging from microelectronics to energy harvesting. Glenn's innovations have enabled a significantly improved matrix composite material with the potential to make a significant impact on the commercial materials market.