Advanced materials for environmental catalysts.

Recent advances in the synthesis and characterization of materials for environmental catalysts are reported in this paper. Highly advanced environmental catalysts for decomposition of volatile organic compounds and nitrogen oxides were artificially designed based on a concept usually employed in the fields of solid-state chemistry and solid-state ionics. Catalytically active materials for complete ethylene oxidation were prepared by a citrate sol-gel method as a key process to obtain CeO(2)-ZrO(2)-Bi(2)O(3) solid solutions. On the other hand, direct NO decomposition catalysts were designed and prepared focusing on the open spaces and oxide anion vacancies in the crystal lattice. Evaluation of the materials as environmental catalysts demonstrated significant advantages over the conventional ones. The design strategy, synthetic method, and structural features of these concerto catalysts are addressed.