Nanoparticle Composite Films for Solar Cells

The cost of photovoltaic energy (PV) is today on the verge of becoming competitive with traditional energy sources (oil, coal etc). However, several achievements must be made before this grid parity is obtained and significant solar energy can be realized in the market. One such achievement would be an increase in the efficiency of converting solar energy into electrical energy. It has been shown that the limit for this efficiency for the traditional single-junction solar cell device is approximately 30%. The introduction of nanoparticle composite thin film materials in solar cell devices challenge the boundary conditions used to determine this limit. Firstly, light scattering off metal nanoparticles showing plasmonic effects will enhance the optical pat h of solar radiation within the light absorbing solar cell. This enhances the total optical absorption. Secondly, the plasmon effects in the same nanoparticles may enhance the local optical field and thus strengthen the conversion of near-IR photons to vi sible photons in frequency optical up-conversion processes in doped dielectric materials. This allows for energy conversion of photons that otherwise are lost. The project will prepare thin film materials of this kind using pulsed laser ablation and expl ore the their optical properties.