Promotion of Hydrogenation of Organic Molecules by Incorporating Iron into Platinum Nanoparticle Catalysts: Displacement of Inactive Reaction Intermediates

作者：Wang Hailiang; Krier James M; Zhu Zhongwei; Melaet Gerome; Wang Yihai; Kennedy Griffin; Alayoglu Selim; An Kwangjin; Somorjai Gabor A^*

来源：ACS Catalysis, 2013, 3(10): 2371-2375.

DOI：10.1021/cs400579j

• Pt-Fe bimetallic nanoparticles
• ethylene hydrogenation
• cyclohexene hydrogenation
• SFG
• AP-XPS

We characterize the surface chemical states of reactants and catalysts under reaction conditions to elucidate the composition effect of platinum iron bimetallic nanoparticles on catalytic hydrogenation of organic molecules. The catalytic,hydrogenation of ethylene is drastically accelerated on the surface of 2 nm PtFe bimetallic nanoparticles as compared to pure Pt. Sum frequency, generation (SFG) vibrational spectroscopy indicates that incorporation of Fe into Pt nanoparticle catalysts weakens the adsorption of ethylidyne, an inactive spectator species, on the catalyst surface. Similarly, the turnover frequency of cydohexene hydrogenation is also significantly enhanced by incorporating Fe into pt nanoparticle catalysts. Ambient-pressure X-ray photoelectron spectroscopy (AP-XPS) reveals the surface composition, and oxidation states of the PtFe,nanoparticles under reaction conditions. The oxidation state distribution of Fe responded to the gas atmosphere and the probing depth, whereas the Pt remained largely metallic an all probing conditions. This work represents a molecular level correlation between. catalyst structure and catalytic performance.

• 出版日期2013-10