Stability of Catalytic Nanoparticles on Substrates with Artificially Controlled Surface Topology
EMSL Project ID
47759
Abstract
Catalytic reactions play a major role in chemical industry and other areas such as transportation. Improving catalytic efficiency and selectivity has a strong impact on energy efficiency, one of DOE’s major challenges. Efficiency of metallic nanoparticles can be improved by decreasing the size of the particles. The size range between 0.5nm and 4nm appears to be especially effective and particles of that size also demonstrate high selectivity to certain chemical reactions [1]. These improved catalytic properties come at the price of lower stability which is one of the major problems for commercial application of these small nanoparticles.It has been suggested that structured surfaces [2] could provide a solution to this problem. A surface with dimples slightly larger than the particles should confine the catalyst to defined areas. We expect a significant decrease in mobility of the whole particle and individual atoms on the substrate surface of the particle which should stabilize the size and the shape of the catalyst. The particle environment on a structured surface differs strongly from flat surfaces. We propose to investigate the shape, structure and chemistry of very small Pt particles on structured surfaces in an environment where temperature and pressure is controlled. In this environment we will be able to test the hypothesis that this structured surface reduces mobility of the nanoparticles and diffusion of single atoms on the substrate surface between particles. Reduced mobility and diffusion should also diminish particle growth which is unfavorable because it reduces catalytic efficiency. This investigation will also increase our understanding of the relation between surface properties and of surface processes (diffusion, chemical reaction) beyond the catalytic system suggested in section 2.
Project Details
Start Date
2013-01-17
End Date
2014-01-19
Status
Closed
Released Data Link
Team
Principal Investigator