Separation of Oxygen from Air by (Co(II)(bpy)(terpy)) Complexes in Zeolite Y

摘要

Oxygen adducts of transition-metal complexes have been intensively studied, mainly because of their role as model compounds to elucidate the function of biological oxygenation systems or natural oxygen carriers such as hemoglobin or myoglobin. Cobalt oxygen complexes have been investigated thoroughly. Most mononuclear cobalt-oxygen complexes synthesized in the liquid phase are rather unstable and are transformed into dinuclear forms unless they have ligands large enough to prevent dimerization. Moreover, some of the ligands may be oxidized be oxygen and the ability of the complexes to combine with oxygen may decrease. In order to utilize cobalt effectively by preventing dinuclear complex formation and to make a complex that is resistant to oxidative degradation, we have synthesized mononuclear (CoII(bpy)(terpy)2+ complexes inside the large cavities of a Y-type zeolite. This complex has one vacant coordination site and adsorbs oxygen reversibly.