Oxygen partial pressure control for microgravity experiments

A system consisting of a high-temperature yttrium-stabilized zirconia (YSZ) based oxygen ion pump and potentiometric sensor enables precise measurement and control of oxygen partial pressure, pO2, at elevated temperatures within 0.2 to 10^-20 bar. <the principle of operation as well as the influence of temperature and gas buffers like H2/H2O on the pO2 is discussed. The ion pump is controlled by a microcontroller system and adjusts the oxygen partial pressure with an uncertainty of Delta-log(pO2)