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用红外光谱(IR)及程序升温分解-质谱(TPDE-MS)联用技术研究了[Pt_3(CO)_6]_5[N(C_2H_5)_4]_2/Al_2O_3簇负载型催化剂的脱羰活化过程。IR结果表明,[Pt_3(CO)_6]_5~(2-)在真空中羰基随温度升高而脱除,180℃时脱除干净,其中线式羰基配位体的吸-脱附是可逆的,而桥式羰基配位体的吸-脱附是不可逆的。TPDE-MS结果表明,该络合物的分解基本可分为两部分,在140-220℃首先发生羰基脱除反应,随着温度的升高,在约220℃—410℃的范围内络合物的配体[N(C_2H_5)_4]~+也发生了分解。该络合物在H_2气流中的分解比在Ar气流中较易进行。经480℃氢还原处理后络合物羰基的脱除及配体的分解都已基本完成。
The decarbonylation activation of [Pt_3 (CO) _6] _5 [N (C_2H_5) _4] _2 / Al_2O_3 clusters was investigated by infrared spectroscopy (IR) and temperature programmed desorption / mass spectrometry (TPDE-MS) The results of IR indicated that the carbonyl group of [Pt_3 (CO) _6] _5 ~ (2-) was removed with the increase of temperature under vacuum and was removed at 180 ℃. The absorption and desorption of linear carbonyl ligand was reversible While the absorption-desorption of bridged carbonyl ligands is irreversible. TPDE-MS results showed that the decomposition of the complex can be basically divided into two parts, the carbonyl removal reaction occurs first at 140-220 ℃, with the temperature increasing, complexed in the range of about 220 ℃ -410 ℃ The ligand [N (C_2H_5) _4] ~ + also decomposed. The decomposition of this complex in the H 2 gas stream is easier than in the Ar gas stream. After 480 ℃ hydrogen reduction complex carbonyl removal and ligand decomposition have been basically completed.