COLLABORATIVE RESEARCH AND DEVELOPMENT (CR&D) Task Order 0035: Incorporation of Metal Nanoshells into Photovoltaic Devices

This research in support of the Air Force Research Laboratory Materials and Manufacturing Directorate was conducted at Wright-Patterson AFB, Ohio from 8 June 2005 through 7 June 2007. The plasmon resonance in metallic nanoshells can be used to efficiently harvest solar energy and convert it into thermal or electronic form. Possible applications include improved optical coupling into silicon photodiodes, solar water heaters, and photocatalysis. We use standard optimization algorithms to theoretically determine the best mixture of different nanoshell species ([core, shell] sizes) for two practical scenarios. We show that a mixture of nanoshell species [r1, r2] = [47, 58] nm and [r1, r2] = [28, 42] nm in a 6:5 volume ratio is optimal for absorbing AM 1.5 sunlight when deposited on a silicon surface. Surprisingly, we find that a single particle species is very good for scattering AM 1.5 light on a glass surface, and that very little benefit is gained by mixing different shells. Assumptions and approximations made in the analysis are discussed. The original document contains color images. All DTIC reproductions will be in black and white.