Atomically Precise Metal Nanoclusters for Catalytic Application

Technical Report · Fri Nov 18 04:00:00 EST 2016

DOI:https://doi.org/10.2172/1332684· OSTI ID:1332684

Jin, Rongchao ^[1]

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1. Carnegie Mellon Univ., Pittsburgh, PA (United States); Carnegie Mellon University

The central goal of this project is to explore the catalytic application of atomically precise gold nanoclusters. By solving the total structures of ligand-protected nanoclusters, we aim to correlate the catalytic properties of metal nanoclusters with their atomic/electronic structures. Such correlation unravel some fundamental aspects of nanocatalysis, such as the nature of particle size effect, origin of catalytic selectivity, particle-support interactions, the identification of catalytically active centers, etc. The well-defined nanocluster catalysts mediate the knowledge gap between single crystal model catalysts and real-world conventional nanocatalysts. These nanoclusters also hold great promise in catalyzing certain types of reactions with extraordinarily high selectivity. These aims are in line with the overall goals of the catalytic science and technology of DOE and advance the BES mission “to support fundamental research to understand, predict, and ultimately control matter and energy at the level of electrons, atoms, and molecules”. Our group has successfully prepared different sized, robust gold nanoclusters protected by thiolates, such as Au₂₅(SR)₁₈, Au₂₈(SR)₂₀, Au₃₈(SR)₂₄, Au₉₉(SR)₄₂, Au₁₄₄(SR)₆₀, etc. Some of these nanoclusters have been crystallographically characterized through X-ray crystallography. These ultrasmall nanoclusters (< 2 nm diameter) exhibit discrete electronic structures due to quantum size effect, as opposed to quasicontinuous band structure of conventional metal nanoparticles or bulk metals. The available atomic structures (metal core plus surface ligands) of nanoclusters serve as the basis for structure-property correlations. We have investigated the unique catalytic properties of nanoclusters (i.e. not observed in conventional nanogold catalysts) and revealed the structure-selectivity relationships. Highlights of our works include: i) Effects of ligand, cluster charge state, and size on the catalytic reactivity in CO oxidation, semihydrogenation of alkynes; ii) Size-controlled synthesis of Au-n clusters and structural elucidation; iii) Catalytic mechanisms and correlation with structures of cluster catalyst; iv) Catalytic properties of Au nanorods in chemoselective hydrogenation of nitrobenzaldehyde and visible light driven photocatalytic reactions.

• Research Organization: Carnegie Mellon Univ., Pittsburgh, PA (United States)
• Sponsoring Organization: USDOE Office of Science (SC), Basic Energy Sciences (BES) (SC-22)
• DOE Contract Number: SC0008813
• OSTI ID: 1332684
• Report Number(s): DOE-CMU--0008813; 4122689448
• Country of Publication: United States
• Language: English

Related Subjects

02 PETROLEUM
77 NANOSCIENCE AND NANOTECHNOLOGY
Metal nanoclusters
atomic precision
structure-activity relationships