This Small Business Innovation Research Phase (SBIR) I project aims to develop a new class of solar cell based on an internal photoemission device geometrically configured as a near perfect, broadband, isotropic absorber. Realizing the potential of this technology would bring to market a solar cell that is commercially competitive with other solar technologies on a cost per watt basis and are able to fabricate on a flexible substrate. Internal photo-emission converters have received renewed interest, but published power conversion efficiencies are well below the theoretical limit. A primary limiting factor in previous attempts has been limited light absorption in the metal. Our preliminary simulations and tests show enhanced light absorption across a broad range of angles and wavelengths when the absorbing metal is configured in a nanocomposite layer in a perfect absorber structure. The objective of Phase I is to validate the preliminary simulations by fabricating and testing a functioning device. The broader impact/commercial potential of this project is primarily in the field of solar energy conversion. Successful completion of Phase I and Phase II of this research and development effort will enable commercialization of a low cost and long lifetime solar cell technology that can be manufactured on a flexible substrate using roll-to-roll processing techniques. This technology will provide a new cost competitive entry into the flexible and conformable solar cell market.
