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在NaY分子筛超笼内合成了桔黄色的[Pt_9(CO)_(18)]~(2-)和深绿色的[Pt_(12)(CO)_(24)]~(2-)簇合物。前者给出2056和1798cm~(-1)的线式和桥式羰基特征红外谱带;后者给出2080和1824cm~(-1)谱带。与在THF溶液中结果相比,NaY内合成的羰基簇合物的线式v_(CO)向高波数位移,而桥式v_(CO)向低波数位移。EXAFS为Pt羰基簇合物在分子筛内的规整形成提供了证据。NaY内Pt_9和Pt_(12)羰基簇合物在NO+CO反应中显示了较高的催化活性及稳定性。
The orange [Pt_9 (CO) _ (18)] ~ (2-) and dark green [Pt_ (12) (CO) _ (24)] ~ (2-) clusters were synthesized in NaY zeolite Things. The former gives 2056 and 1798cm -1 linear and bridge carbonyl infrared bands; the latter gives 2080 and 1824cm -1 bands. Compared with the results in THF solution, the linear v_ (CO) of the carbonyl cluster synthesized in NaY shifts to the high wavenumber, while the bridge v_ (CO) shifts to the low wavenumber. EXAFS provides evidence for the regular formation of Pt carbonyl clusters within the molecular sieve. The Pt_9 and Pt_ (12) carbonyl clusters in NaY show higher catalytic activity and stability in NO + CO reaction.