Plasmonic nanocomposites for solar harvesting


Study and utilization of metallic nanoparticles in solar harvesting applications. When metallic nanoparticles are illuminated by electromagnetic waves, their free electrons oscillate in response to the electric field. At the right frequency this oscillation is driven into resonance (Surface Plasmon Resonance), exhibiting huge polarization fields on the nanoparticle surface. These fields induce strong light scattering and promote photo-electrical processes (e.g. fluorescence, Raman scattering, light absorption). In addition, these fields are very sensitive to the metal type as well as the nanoparticle shape, size and dielectric environment, allowing great flexibility in designing applications. Metallic nanoparticles are in the heart on nanotechnology, with applications in medicine, energy and photonics. In this project we use the properties of the metallic nanoparticles to improve and optimize the performance of: 1) photovoltaic cells, through a) enhancing the semiconductor absorption, and b) solar spectrum conversion for better utilization of all available photons, 2) solar collectors, through designing a nanostructured metallodielctric coating exhibiting total absorption to the solar spectrum and minimal losses from thermal re-radiation.

Herakleitos II Project funded from:
HERAKLEITOS II (2011-2014)
co-financed by the European Union (ESF) and Greek national funds (NSRF)
Principal Investigator: E. Lidorikis

FP7 FP7 NMP.2012.1.4-1: Smartonics (2013-2017)
Principal Investigator: Aristotle University of Thessaloniki
UOI coordinator: E. Lidorikis

Optical properties and applications of carbon-based materials


Carbon nanotubes (CNTs), and more recently graphene, have been at the center of nanotechology research, with the search for new technologies based on their mechanical and electrical properties ever increasing. Graphene, a two-dimensional honeycomb lattice of carbon atoms, can be thought of as the "building block" of other carbon allotropes: it can be "wrapped" into fullerenes, "rolled" into CNTs or "stacked up" into graphite, with many of their properties deriving from graphene. In this project we study different aspects of the photonic response and applications of graphene and CNTs. We have developed a theoretical understanding for graphene's enhanced visibility on certain substrates, as well as interference-enhanced (IERS) and surface-enhanced Raman scattering (SERS) phenomena in graphene. We have investigated the photonic properties of two-dimensional CNT arrays for photon energies up to 40eV and unveiled the physics of two distinct applications, namely deep-UV photonic crystals and total visible absorbers. We study graphene's optical absorption, and design graphene and hybrid graphene/plasmonic optical detectors and photovoltaic systems.

Graphene Flagship
Project is part of the Graphene Flagship
UOI coordinator: E. Lidorikis