Laser ablation has been used ex situ to create metal nanoparticles for introduction into a reactive pyrolysis flame. By prior synthesis of the metal nanoparticles, the effects of the reactive gases can be clearly separated from the pyrolysis chemistry of a solvent carrier, as when nebulized solutions are used. Moreover, varying reactivity issues associated with particle growth and size are bypassed. Our results show that Fe selectively reacts with CO to produce nanotubes, whereas Ni selectively reacts with C 2H 2 to produce nanofibers. These observations are interpreted through the donation and withdrawal of electron density between the adsorbate's molecular orbitals and surface atoms of the metal nanoparticle. The rate of reaction of Ni with only C 2H 2 is found to be greater than the rate with C 2H 2 and CO. This suggests that CO inhibits the Ni-catalyzed reaction.
All Science Journal Classification (ASJC) codes
- General Chemistry
- Biomedical Engineering
- General Materials Science
- Condensed Matter Physics