Cov hlau saum npoo tsis tas yuav tsim cov khoom lag luam zaj duab xis kom passivate, thiab ntev npaum li qhov saum npoo los yog ib feem ntawm qhov saum npoo tsim ib txheej ntawm cov pa oxygen los yog ib qho adsorption txheej ntawm cov pa uas muaj cov pa (xws li O2- lossis OH-), nws yog txaus los ua passivation.
