A CONTINUOUS AND EFFICIENT O2 SUPPLY FROM THE MARTIAN ATMOSPHERE
Sean R. Koebley
Advisor: Dr. R.A. Outlaw
Applied Science Department
College of William and Mary
Abstract
A crucial component of a manned mission to Mars promises to be the in-situ resource
utilization of the Martian CO2 atmosphere to produce O2 for respiration and propellant. A viable
alternative to the currently preferred technique of electrolytic in-situ oxygen production is the
permeation of atomic oxygen through a Ag membrane. Key steps in the permeation process were
identified, and the interplay between a number of parameters (temperature, membrane thickness,
diffusivity, Ag reorganization) was investigated in the hope of identifying the conditions that
optimize the O2 flux. A sustainable glow discharge of the Martian atmosphere was shown to
improve the availability of supply-side atomic oxygen by dissociation of ambient 5 Torr CO2.
Membrane temperature and thickness were experimentally and theoretically varied to determine
the highest variation of flux for the lowest energy budget, yielding a parameterization that could
theoretically sustain a team of astronauts with only a few square meters of permeating Ag thin
film membrane. An oxygen-induced reorganization of the Ag microstructure observed near
500°C is also suggested to provide greater diffusivity at a lower energy cost. An energy
optimization study is recommended to experimentally verify the conditions that produce the
requisite flux at the lowest energy cost.
Koebley
Page 1