The Preparation, Characterization, H2-sorptionand ,Catalytic Activity of Pt- and Pd-containing Mesoporous silicas

含鉑及鈀金屬之中孔洞二氧化矽之製備,鑑定,催化與儲氫性質研究

王律之(Lu-Chih Wang)

指導教授 ： 趙桂蓉

國立清華大學/理學院/化學系/博士(2009年)

摘要

This study includes the preparation and characterization of platinum and palladium nanoparticles incorporated on mesoporous silicas as well as the hydrogen sorption on Pd nanoparticles.
Two methods were preceded to prepare the metal incorporated mesoporous silicas, i.e., one-pot synthesis under the control of pH value in reactant mixtures and CVD in SC-CO2 medium. The formations of Pd(0) nanoparticles and mesophases were expected to occur simultaneously in basic media in one-pot synthesis. Pt incorporated mesoporous silicas were synthesized by contacting calcined MCM-48 with Pt(hfac)2 and Pt(acac)2 in SC-CO2 medium, and then, their Pt precursors were reduced by hydrogen at room temperature or 200 oC.
Due to the confinement effect of metal nanoparticles inside the mesochannels, the enhancement on catalytic activity and selectivity of trans/cis 1,4-dimethylcyclohexanes ratio in the hydrogenation of p-xylene was observed on Pd/MCM-41 and Pt/MCM-48 prepared by using Pt(acac)2 as Pt precursors through SC-CO2 treatment.
In addition, the hydrogen sorption on Pd nanoparticles stabilized by surfactant containing in mesoporous silicas was compared with that on Pd nanoparticles stabilized only by surfactant and on Pd membrane. The Pd-Pd bond distances were found to be increased after hydrogen sorption, with the amount of bond expansion increased with metal size and amount of hydrogen adsorption.

關鍵字

中孔洞二氧化矽 ； 鉑金屬 ； 鈀金屬 ； 儲氫 ； 催化

並列摘要

無資料

並列關鍵字

Mesoporous silicas ； Catalytic Activity ； Platium ； H2-sorption ； Palladium

參考文獻

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