Dye-sensitized solar cells (DSSC) may provide an economical alternative to the present p-n junction photovoltaic devices. Here the relation between chlorophyll purity and photovoltaic performance was examined. Also the commercial grade copper chlorophyll was examined. The performance under simulated sunlight and the quantum efficiency were measured. All samples had large short wavelength quantum efficiency however the high purity chlorophyll had larger quantum efficiency in the visible. The highest purity samples produced DSSC solar cells with the highest open circuit voltage and efficiency while the fill factor and the short circuit current were not strongly correlated with purity. The un-altered short circuit current suggests that chlorophyll attachment and charge transfer at the titanium oxide are not altered by impurities. However the results suggest that impurities (and/or copper in the commercial chlorophyll case) alter the photo-absorption and the electrolyte so as to either change the iodine chemical potential or decrease the diffusivity of iodine ions.

A detailed analysis of photovoltaic front surface phosphor-based spectral modification and light scattering by hetero-structure was conducted. Phosphor based spectral downconversion is a well known laser technology. The analysis assumes that both sunlight energy and photovoltaic performance are at peak sunlight photon flux within the spectral range. Further, the analysis presented here indicates that parasitic losses and light scattering within the spectral range are large enough to offset any expected gains. For example, analysis of up-conversion phosphor-based approaches indicates that these are likely to suffer unexpectedly large losses in the peak spectral region due to parasitic absorption when attempting to down convert UV light.

The innovation ecosystem provides benefits and challenges for multiple institutional actors like universities, industry, government, NGOs, and private funding agencies, as well as individuals in a rapidly evolving and dynamic environment. First, we describe the changing role of universities-whereby, the support of innovation and entrepreneurship is developing into a core mission of universities. We then describe strategies within the United States and globally to help students learn about innovation and entrepreneurship. Finally, we explore the benefits and challenges of technological innovation for economic development, emphasizing how such development relates to the global problem of underprivileged communities, both in developed and developing countries, and the special concerns of economic development for developing countries.

Layers that enhance light scattering and Raman-scattering-based spectral modification for solar cell applications were investigated. Titanium-oxide based rear diffuse reflector were found to increase the long wavelength response of crystalline solar cells. Also particle within the Titanium-oxide produce a far greater Stokes and anti-Stokes shift when compared to bulk crystal counterparts. The anti-Stokes to Stokes shift ratio in these particle systems is also greater and increased with increasing probe or bias light intensity. When applied to solar cells these layers extend the red response and thereby increase the overall performance.

Raman-based spectral modification for improved solar cell (SC) performance was investigated. While, Raman scattering is a weak phenomena commonly used for material characterization, small-sized particles embedded in a light scattering matrix have increased Raman and increased anti-Stokes energy up shift probability; because, embedding particles in a diffusive, transparent matrix vastly increases light path lengths (kilometers) and because optically generated phonons contribute to anti-Stokes probability in long phonon lifetime small particles. Increased long wavelength quantum efficiency was obtained using these layers on silicon SCs. Diffusion theory was applied to the spatial light diffusion and to Raman light energy broadening.