Cerium-modified amorphous manganese oxides for efficient catalytic removal of ozone

Abstract

Manganese-based catalysts were widely developed for catalytic removal of ozone, and the low stability and water inactivation are major challenges. To improve removal performance of ozone, three methods were applied to modify amorphous manganese oxides, including acidification, calcination and Ce modification. The physiochemical properties of prepared samples were characterized, and the catalytic activity for ozone removal was evaluated. All modification methods can promote the removal of ozone by amorphous manganese oxides, and Ce modification showed the most significant enhancement. It was confirmed that the introduction of Ce markedly changed the amount and property of oxygen vacancies in amorphous manganese oxides. Superior catalytic activity of Ce-MnO_x can be ascribed to its more content and enhanced formation ability of oxygen vacancies, larger specific surface area and higher oxygen mobility. Furthermore, the durability tests under high relative humidity (80%) determined that Ce-MnO_x showed excellent stability and water resistance. These demonstrate the promising potential of amorphously Ce-modified manganese oxides for catalytic removal of ozone.