In situ gas-phase catalytic properties of TiC-supported size-selected gold nanoparticles synthesized by diblock copolymer encapsulation
Abbreviated Journal Title
catalysis; gold nanoparticle; titanium carbide; carbon monoxide; oxygen; diblock copolymer; thermal desorption spectroscopy; atomic force; microscopy (AFM); X-ray photoelectron spectroscopy (XPS); transmission; electron microscopy (TEM); surface structure, morphology, roughness, and; topography; TRANSITION-METAL CARBIDES; TEMPERATURE CO OXIDATION; BULK MIXED; CARBIDES; AU NANOPARTICLES; ELECTRICAL-PROPERTIES; AU/TIO2 CATALYSTS; DIAMOND INTERFACE; CHEMICAL NATURE; FORMING METAL; SURFACE; Chemistry, Physical; Physics, Condensed Matter
TiC-supported size- and shape-selected Au nanoparticles with well defined interparticle distances were synthesized by diblock copolymer encapsulation. Atomic force microscopy (AFM), transmission electron microscopy (TEM), X-ray photoelectron spectroscopy (XPS) and temperature programmed desorption (TPD) have been used to investigate the correlation between the nanocatalyst morphological/electronic structure and its chemical reactivity. Using the low-temperature oxidation of CO as a model reaction, our TPD results showed an enhancement of the catalytic activity with decreasing particle size. Two desorption features were observed and assigned to kinks/steps in the gold surface and the Au-TiC interface. The role of the interparticle distance on the activity is discussed. AFM measurements showed drastic morphological changes (Ostwald ripening) on the nanoparticles after CO oxidation when the initial interparticle distance was small (similar to 30 nm). However, no sintering was observed for Au nanoparticles more widely spaced (similar to 80 nm). (c) 2006 Elsevier B.V. All rights reserved.
"In situ gas-phase catalytic properties of TiC-supported size-selected gold nanoparticles synthesized by diblock copolymer encapsulation" (2006). Faculty Bibliography 2000s. 6485.