CNN reports:

The first experiment to produce oxygen on another planet has come to an end on Mars after exceeding NASA’s initial goals and demonstrating capabilities that could help future astronauts explore the red planet. The microwave-size device called MOXIE, or Mars Oxygen In-Situ Resource Utilization Experiment, is on the Perseverance rover.

The experiment kicked off more than two years ago, a few months after the rover landed on Mars. Since then, MOXIE has generated 122 grams of oxygen, equal to what a small dog breathes in 10 hours, according to NASA. The instrument works by converting some of Mars’ plentiful carbon dioxide into oxygen. During the peak of its efficiency, MOXIE produced 12 grams of oxygen an hour at 98% purity or better, which is twice as much as NASA’s goals for the instrument. On August 7, MOXIE operated for the 16th and final time, having completed all its requirements…

Bigger and better versions of something such as MOXIE in the future could supply life support systems with breathable air and convert and store oxygen needed for rocket fuel used to launch on a return trip to Earth.
In a statement NASA applauded the performance of the MIT-created experiment. “When the first astronauts land on Mars, they may have the descendants of a microwave-oven-size device to thank for the air they breathe and the rocket propellant that gets them home…

“Rather than bringing large quantities of oxygen with them to Mars, future astronauts could live off the land, using materials they find on the planet’s surface to survive.”