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Silver biocide offers a potential advantage over iodine, the current state-of-the-art in US spacecraft disinfection technology, in that silver can be safely consumed by the crew. As such, silver may reduce the overall complexity and mass of future spacecraft potable water systems, particularly those used to support long duration missions. A primary technology gap identified for the use of silver biocide is one of material compatibility. Wetted materials of construction are required to be selected such that silver ion concentrations can be maintained at biocidally effective levels.

This project sought to develop a photocatalytic oxidation (PCO) based total organic carbon (TOC) analyzer for real time monitoring of air quality in spacecraft. Specific requirements for this application were to convert volatile organic contaminants (VOC) into CO2 stoichiometrically in a single pass through a small reactor with low power requirement. One of the greatest challenges of this TiO2-mediated PCO was the incomplete oxidation of some recalcitrant VOCs leading to less reactive intermediates that deactivate the catalyst over time. Dichloromethane (DCM) is one of these VOCs. The effect of some design factors (e.g. TiO2 catalyst surface area to volume ratio and UV photon flux field) as well as operating conditions of an annular reactor (e.g. VOC residence time and relative humidity) on the efficiency in converting DCM to CO2 were investigated.

Light-emitting diodes (LEDs) represent an innovative artificial lighting source with several appealing features specific for supporting plants, whether on space-based transit vehicles or planetary life support systems. Appropriate combinations of red and blue LEDs have great potential for use as a light source to drive photosynthesis due to the ability to tailor irradiance output near the peak absorption regions of chlorophyll. This paper describes the importance of far-red radiation and blue light associated with narrow-spectrum LED light emission. In instances where plants were grown under lighting sources in which the ratio of blue light (400–500 nm) relative to far-red light (700–800 nm) was low, there was a distinct leaf stretching or broadening response. This photomorphogenic response sanctioned those canopies as a whole to reach earlier critical leaf area indexes (LAI) as opposed to plants grown under lighting regimes with higher blue:far-red ratios.