Metastable and Nanostructured Materials

Nanoparticles - Particle-substrate interactions

Unlike solution chemistry-based approaches, preparation of nanoparticles from the gas phase does not provide for any regular arrangement of the particles on a substrate. Therefore, either the chemistry required for the self-assembly is stored on the substrate [A. Terheiden et al., Appl. Phys. Lett. 84 (2004) 3891 and J. Chem. Phys. 121 (2004) 510] or the substrate carries a template with a periodic structure or a periodic chemical affinity to the particles to be deposited. We study the feasibility of biological templates such as S-Layers of bacteria for the induced regular arrangement of metallic nanoparticles. Current studies that combine experimental and simulation techniques aim at quantifying the chemical affinity of the particles to specific sites of the bio-template.

Left: TEM image of FePt particles on a S-Layer. Middle: Statistical analysis of the site occupancy. The A site is clearly preferred. Right: AFM image of a similar bacteria [H. Engelhardt et al., J. Bacteriol. 168 (1986) 309]. The red circle indicates the position of site A.

Further reading:
U. Queitsch et al., Appl. Phys. Lett. 87 (2007) 113114 URL
U. Quietsch et al., IEEE Trans. Mag. 44 (2008) 2756 URL
U. Queitsch et al., J. Appl. Phys. D 41 (2008) 134019 URL
U. Queitsch et al., J. Phys. Chem. C 113 (2009) 10471 URL



Dr. Darius Pohl
Phone: +49-351-4659-758