Layer-by-Layer Growth of Charged Polymers and Silicon Nanoparticles

We investigate the use of semiconductor nanoparticles in a polymer-semiconductor layer-by-layer growth procedure. We use polyelectrolytes for charged polymers and H-terminated Si nanoparticles for the semiconductor. Microclusters of calcium carbonates are used as charged templates. Our results show that the nanoparticles adsorb on positively as well as on negatively charged polymer layers. But, particle’s adsorption is more efficient on negatively charged polymers. The results are analyzed in terms of electrostatic polarization forces. Dissolution of the calcium carbonate template into calcium ions and carbon dioxide while retaining the silicon nanoparticles creates luminescent polymer-silicon capsules. The permeability versus robustness of polymer multilayers is investigated. Optically functionalized capsules may find applications in optical marking/tracking for biomedical applications as well as for underground water and oil exploration.