Human presence on the Moon requires oxygen gas production. On the Moon’s surface, O2 can exist on the regolith as Reactive Oxygen Species (ROS), such as metal superoxide (O2•–; e.g., KO2), hydroxyl radicals (•OH), and hydrogen peroxide (H2O2).
We propose a system, OxR (Oxygen Release), that can extract and measure O2 from the Moon's regolith ROS superoxide and H2O2 by subjecting them to sequential O2-release reactions with simple radiation-resistant inorganic reagents, presented in earlier published studies. OxR can be scaled to produce sustainable O2 gas, since ROS is continuously produced on planetary regolith by cosmic radiation (“Oxygen farming"). OxR can also detect ROS for selecting sites least toxic to astronauts for manned space stations, and least oxidative for searching organic markers of extraterrestrial life on other planetary and icy worlds (Mars, Titan, Europa, Enceladus).
OxR is a novel, temp/pressure-controlled microfluidics, small footprint device, with reagent reconstitution/delivery parts, and a solid-state optical sensing O2-electrode (detection limit of 1 ppb for aqueous/gaseous O2). OxR can simultaneously detect •OH by a probe and measure of the specific product by a fluorescence detector. Preliminary OxR will be tested on mineral powders and regolith simulants (i.e., anorthosites), ices, lunar meteorites, and lunar rocks; lunar dust will be simulated by ablation of minerals with high-power Nd:YAG pulsed lasers, expecting for ROS to form. Samples will be characterised analytically.
Device concepts to be tested exist (i.e., durable metal-housing, or teflon housings containing UV-cuvettes). The developed system will be automated and will measure O2 gas release and •OH concentration in three sequential steps. ROS-containing lunar regolith is a few meters thick. Irradiation-regenerated ROS is a surface effect, covering large areas to be utilised for "oxygen farming". Based on the demo devices, a lab-on-a-chip microfluidics device will be proposed.
