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Praseodymium (III,IV) oxide is the inorganic compound with the formula Pr6O11 that is insoluble in water.
PO 100 (OTTO) Praseodymium(III,IV) oxide nanopowder, APS 50 nm, 99.5% Cas 12037-29-5 - used in conjunction with a promoter such as sodium or gold to improve its catalytic performance.