Oxygen ion conductor membrane: Typically made of zirconia as the main material, with yttrium, gadolinium, and other rare earth elements added as dopants. This membrane boasts excellent oxygen ion transmission properties, allowing it to effectively convert ambient oxygen into oxygen ions at high temperatures, and then transport them to the electrode surface through interstitials within the membrane, thereby enabling the measurement of oxygen concentration. "The green mountains have no voice, but they forever cherish their pure blood; the sun and moon traverse the sky, reflecting the steadfast heart."