Sum Frequency Generation and Catalytic Reaction Studies of the Removal of Organic Capping Agents from Pt Nanoparticles by UV−Ozone Treatment

Aliaga, César; Park, Jeong Young; Yamada, Yusuke; Lee, Hyun Sook; Tsung, Chia‐Kuang; Yang, Peidong; Somorjai, Gábor A.

doi:10.1021/jp8108946

Cited by 266 publications

(242 citation statements)

References 32 publications

Supporting

Mentioning

231

Contrasting

Unclassified

Order By: Relevance

“…Recently, a number of studies have applied this technique to the nanostructured surfaces [80][81][82]. A general observation in these studies is the reduction of the sum frequency signal due to the nanometer scale corrugation on sample surfaces.…”

Section: Discussionmentioning

confidence: 99%

Major Successes of Theory-and-Experiment-Combined Studies in Surface Chemistry and Heterogeneous Catalysis

Somorjai

2010

Top Catal

Self Cite

View full text Add to dashboard Cite

Experimental discoveries followed by theoretical interpretations that pave the way of further advances by experimentalists is a developing pattern in modern surface chemistry and catalysis. The revolution of modern surface science started with the development of surfacesensitive techniques such as LEED, XPS, AES, ISS and SIMS, in which the close collaboration between experimentalists and theorists led to the quantitative determination of surface structure and composition. The experimental discovery of the chemical activity of surface defects and the trends in the reactivity of transitional metals followed by the explanations from the theoretical studies led to the molecular level understanding of active sites in catalysis. The molecular level knowledge, in turn, provided a guide for experiments to search for new generation of catalysts. These and many other examples of successes in experiment-and-theory-combined studies demonstrate the importance of the collaboration between experimentalists and theorists in the development of modern surface science.

show abstract

Section: Discussionmentioning

confidence: 99%

Major Successes of Theory-and-Experiment-Combined Studies in Surface Chemistry and Heterogeneous Catalysis

Somorjai

2010

Top Catal

Self Cite

View full text Add to dashboard Cite

show abstract

“…The capping agents of the nanocrystals were removed by UV/ozone treatment to form clean metal-metal oxide interfaces. 20 After the capping agent removal, the vertical clefts between the nanocrystals assure access to both catalytic interfaces, while providing high surface area in the close packed array.…”

mentioning

confidence: 99%

Nanocrystal bilayer for tandem catalysis

et al. 2011

Self Cite

View full text Add to dashboard Cite

High performance catalysts are central for the development of new generation energy conversion and storage technologies. 1,2 While industrial catalysts can be optimized empirically by tuning the elemental composition, changing the supports, or altering preparation conditions in order to achieve higher activity and selectivity, these conventional catalysts are typically not uniform in composition and/or surface structure at the nano-to micro-scale. In order to significantly improve our capability of designing better catalysts, new concepts for the rational design and assembly of metal-metal oxide interfaces are desired. Metal nanocrystals with well-controlled shape and size are interesting materials for catalyst design from both electronic structure and surface structure aspects. 3,4,5 From the electronic structure point of view, small metal nanoclusters have size-dependent electronic states, which make them fundamentally different from the bulk. From the surface structure point of view, the shaped nanocrystals have surfaces with well-defined atomic arrangements. It has been clearly demonstrated by surface science studies in recent decades that the atomic arrangement on the crystal surface can affect catalytic phenomena in terms of activity, selectivity, and durability.

show abstract

“…Our recent SFG studies indicate that during hydrogenation of pyridine, pyridinium ions are the reaction intermediates and the formation of piperidine as the product of complete hydrogenation in the gas phase 48 . SFGVS of ethylene hydrogenation on the clean platinum nanoparticles after UV-ozone cleaning showed existence of ethylidyne and di-σ-bonded species, indicating the similarity between single-crystal and nanoparticle systems 58 .…”

Section: Reaction Intermediates Detected By Sfg Vibrational Spectroscopymentioning

confidence: 93%

“…High pressure SFG can also be used to study reaction intermediates on nanoparticle surfaces. For SFG measurements on nanoparticles, two dimensional nanoparticle arrays are deposited on a prism which allows for total internal reflection to increase the detection sensitivity 58,59 . Our recent SFG studies indicate that during hydrogenation of pyridine, pyridinium ions are the reaction intermediates and the formation of piperidine as the product of complete hydrogenation in the gas phase 48 .…”

Section: Reaction Intermediates Detected By Sfg Vibrational Spectroscopymentioning

confidence: 99%

Advancing the Frontiers in Nanocatalysis, Biointerfaces, and Renewable Energy Conversion by Innovations of Surface Techniques

2009

Self Cite

View full text Add to dashboard Cite

The challenge of chemistry in the 21 st century is to achieve 100% selectivity of the desired product molecule in multi-path reactions (green chemistry) and develop renewable energy based processes. Surface chemistry and catalysis play key roles in this enterprise. Development of in-situ surface techniques such as high pressure scanning tunneling microscopy (STM), sum frequency generation (SFG) vibrational spectroscopy, time-resolved Fourier Transform Infrared (FT-IR) methods and ambient pressure X-ray photoelectron spectroscopy (AP-XPS) enabled the rapid advancing of three fields; nanocatalysts, biointerfaces, and renewable energy conversion chemistry. In materials nanoscience, synthetic methods have been developed to produce monodisperse metal and oxide nanoparticles (NP) in the 0.8 -10 nm range with controlled shape, oxidation states, and composition, which can be used as selective catalysts since chemical selectivity appears to be dependent on all of these experimental parameters. New spectroscopic and microscopic techniques have been developed that operate under reaction conditions and reveal the dynamic change of molecular structure of catalysts and adsorbed molecules as the reactions proceed with changes in reaction intermediates, catalyst composition, and oxidation states. SFG vibrational spectroscopy detects amino acids, peptides and proteins adsorbed at hydrophobic and hydrophilic interfaces and monitors the change of surface structure and interactions with coadsorbed water. Exothermic reactions and photons generate hot electrons in metal nanoparticles that may be utilized in chemical energy conversion. The photo-splitting of water and carbon dioxide that are important research directions in renewable energy conversion is discussed.2

show abstract

Sum Frequency Generation and Catalytic Reaction Studies of the Removal of Organic Capping Agents from Pt Nanoparticles by UV−Ozone Treatment

Cited by 266 publications

References 32 publications

Major Successes of Theory-and-Experiment-Combined Studies in Surface Chemistry and Heterogeneous Catalysis

Major Successes of Theory-and-Experiment-Combined Studies in Surface Chemistry and Heterogeneous Catalysis

Nanocrystal bilayer for tandem catalysis

Advancing the Frontiers in Nanocatalysis, Biointerfaces, and Renewable Energy Conversion by Innovations of Surface Techniques

Contact Info

Product

Resources

About